Dietary Patterns for Health-Span and Longevity: A Comprehensive Review of Nutritional Strategies Promoting Lifelong Wellness

Abstract

Background: The pursuit of longevity has long been central to nutritional science, with growing evidence underscoring the profound influence of dietary patterns on lifespan and overall health. While various diets have been associated with improved well-being, their comparative effects on longevity remain to be synthesized comprehensively. Main Findings: This review examines the scientific evidence linking major dietary patterns such as the Mediterranean, DASH (Dietary Approaches to Stop Hypertension), plant-based, Blue Zones, intermittent fasting, caloric restriction, and Nordic diets, to longevity and mortality outcomes. The Mediterranean and DASH diets consistently demonstrate reduced cardiovascular and all-cause mortality, while plant-based and Blue Zones diets emphasize whole, minimally processed foods that enhance metabolic and cardiovascular health. Intermittent fasting and caloric restriction emerge as metabolic modulators with anti-aging potential. The Nordic diet, rich in locally sourced foods like berries and fish, also contributes to lower mortality and improved cardiovascular function. Conclusions: This paper uniquely integrates comparative insights from diverse dietary frameworks, emphasizing their shared principles of nutrient density, moderation, and metabolic balance. By adopting evidence-based elements from these dietary models, individuals can optimize health span and longevity, reinforcing the pivotal role of diet as a cornerstone of preventive and personalized nutrition.

1. Introduction

Longevity, defined as the duration of an individual’s life, has become a focal point of modern health and nutrition research, aiming not only to extend lifespan but also to enhance the quality of life during the additional years. The significant increase in average life expectancy over the past century can be attributed to advances in medicine, public health, and overall living conditions [1]. However, this increase has brought to the fore the challenge of managing chronic diseases that often accompany aging. Contemporary research has increasingly recognized that diet plays a pivotal role in influencing longevity and mitigating age-related health issues. The Mediterranean diet, characterized by a high intake of fruits, vegetables, whole grains, nuts, and olive oil, continues to be linked to reduced risks of cardiovascular diseases and all-cause mortality [1].

Similarly, the (Dietary Approaches to Stop Hypertension) DASH diet, which emphasizes fruits, vegetables, lean proteins, and low-fat dairy products, has been shown to lower mortality rates, particularly from cardiovascular causes [2,3]. Plant-based diets, encompassing vegetarian and vegan regimens, have garnered attention for their potential to reduce the risk of chronic diseases such as diabetes, cardiovascular diseases, and certain cancers, contributing to improved overall mortality rates [4,5]. The Blue Zones diet, inspired by regions with the highest life expectancies like Okinawa and Sardinia, emphasizes whole foods, plant-based meals, and minimal processed foods, showing significant correlations with increased longevity [6,7]. Intermittent fasting, which alternates periods of eating and fasting, has been associated with enhanced metabolic health and longevity [8,9,10]. Additionally, caloric restriction without malnutrition has shown promise in delaying the onset of age-related diseases and extending lifespan [11,12].

The Nordic diet, similar to the Mediterranean diet, focuses on locally sourced foods such as berries, fish, whole grains, and root vegetables, and has been linked to lower mortality and improved cardiovascular health and kidney function [13]. Collectively, these dietary patterns underscore the significant impact of nutritional choices on longevity and highlight the importance of a balanced, nutrient-rich diet in promoting a long and healthy life. The quest for longevity has been a longstanding human endeavour. While genetics play a significant role, lifestyle factors, particularly diet, are crucial determinants of lifespan [14]. Despite growing evidence, research on diet and longevity faces several controversies and limitations. The complexity of human dietary behavior, genetic variability, and lifestyle factors makes it difficult to isolate the effects of specific diets. Moreover, conducting long-term randomized controlled trials on dietary interventions poses ethical and practical challenges, leading to reliance on observational studies that may introduce confounding factors and limit causal inference [14].

While numerous studies have examined the effects of individual dietary patterns on health and longevity, a comprehensive synthesis comparing their underlying mechanisms and shared principles remains limited. The beneficial effects of these dietary patterns may be mediated through several biological pathways, including modulation of inflammatory responses, reduction of oxidative stress, regulation of metabolic and hormonal markers, and favourable alterations in gut microbiota composition. Such mechanisms collectively contribute to improved cellular function, reduced chronic disease risk, and delayed onset of age-related pathologies, thereby supporting longevity [14]. This review aims to bridge that gap by integrating current evidence on major dietary models such as the Mediterranean, DASH, plant-based, Blue Zones, intermittent fasting, caloric restriction, and Nordic diets and evaluating their collective influence on lifespan and disease prevention. The novelty of this review lies in presenting a comparative framework that highlights converging nutritional themes, metabolic pathways, and lifestyle factors contributing to longevity across diverse dietary traditions. This review examines contemporary dietary strategies that have shown promise in enhancing longevity and improving health outcomes, supported by recent scientific evidence.

• Search Strategy and Selection Criteria

To ensure a comprehensive and unbiased overview, a systematic literature search was conducted across multiple scientific databases, including PubMed, Scopus, Web of Science, and Google Scholar. The search encompassed studies published between 2000 and 2024, focusing on the relationship between diet, longevity, and aging-related health outcomes. The following keywords and their combinations were used: “diet and longevity”, “Mediterranean diet and lifespan”, “DASH diet and cardiovascular health”, “plant-based diet and aging”, “Blue Zones diet”, “intermittent fasting and longevity”, “caloric restriction and lifespan”, and “Nordic diet and mortality”. Boolean operators (“AND”, “OR”) were applied to refine the search and capture relevant intersections among these themes.

Original research articles, meta-analyses, systematic reviews, and large-scale cohort studies published in peer-reviewed journals were included. Studies were selected if they reported measurable outcomes related to life expectancy, mortality, or major chronic disease prevention. Articles not available in English, those with small sample sizes, or studies lacking sufficient methodological detail were excluded. Reference lists of key publications were manually screened to identify additional relevant studies.

The selected articles were then evaluated for methodological quality, study design, population diversity, and reported biomarkers related to inflammation, oxidative stress, metabolic regulation, or gut microbiota. This approach allowed for an integrated synthesis of evidence across diverse dietary patterns, emphasizing shared mechanisms and differences in their impact on longevity and healthy aging.

2. The Mediterranean Diet

The Mediterranean diet, renowned for its numerous health benefits, has been the subject of extensive research, particularly in recent years. Its health-promoting properties have been widely documented, with studies consistently linking the Mediterranean diet to improved cardiovascular health, reduced risk of chronic diseases, and increased longevity. Figure 1 explains the Mediterranean Diet, characterized by high intake of olive oil, fruits, vegetables, whole grains, nuts, and seeds, with moderate consumption of dairy, fish, and poultry, and minimal intake of red meat and sweets. Olive oil serves as the primary source of healthy fats, while plant-based foods and lean proteins provide essential nutrients and antioxidants. These components collectively promote cardiovascular health, reduce chronic disease risk (including diabetes, cancer, and obesity), and are linked to increased longevity. Overall, the Mediterranean diet emphasizes balance, moderation, and nutrient-rich food choices for long-term well-being (Figure 1). Aging populations are increasingly affected by neurodegenerative diseases such as Alzheimer’s disease and other types of dementia [14].

2.1. Cardiovascular Health

Cardiovascular disease (CVD) remains the leading cause of mortality globally. Numerous studies have shown that adherence to the Mediterranean diet significantly reduces the risk of CVD. For instance, a systematic review by Martínez et al. reaffirmed the association between the Mediterranean diet and a lower risk of cardiovascular diseases and all-cause mortality [15]. The diet’s emphasis on healthy fats, particularly monounsaturated fats from olive oil and polyunsaturated fats from nuts and fish, plays a crucial role in maintaining heart health [16]. These fats help reduce levels of low-density lipoprotein (LDL) cholesterol, known as “bad” cholesterol, and increase high-density lipoprotein (HDL) cholesterol, known as “good” cholesterol, thereby reducing the risk of atherosclerosis and heart disease.

Studies have highlighted the protective effects of the Mediterranean diet against CVD. The PREDIMED trial demonstrated a significant reduction in major cardiovascular events among individuals adhering to a Mediterranean diet supplemented with extra-virgin olive oil or nuts [15,16]. This dietary pattern, rich in monounsaturated fats, polyphenols, fibre, and omega-3 fatty acids, is associated with improved lipid profiles, reduced inflammation, and enhanced endothelial function [17]. Additionally, meta-analyses have shown that higher Mediterranean diet adherence correlates with lower incidence of coronary artery disease, stroke, and hypertension. These findings underscore the Mediterranean diet’s role in mitigating CVD risk through its cardio-protective and anti-inflammatory properties [17].

2.2. Metabolic Health

The Mediterranean diet has garnered significant attention for its positive impact on metabolic health, particularly concerning type 2 diabetes and obesity. Studies indicate that adherence to this diet is associated with a reduced incidence of type 2 diabetes and improved glycaemic control in those already diagnosed with the disease [18,19]. This is largely attributed to the diet’s emphasis on whole, minimally processed foods rich in fibre, such as fruits, vegetables, and whole grains, which play a crucial role in regulating blood sugar levels.

In older adults who are overweight or obese and have metabolic syndrome, the Mediterranean diet combined with regular physical activity has shown remarkable benefits. This dietary approach has been linked to significant reductions in total and visceral fat, which are key factors in managing metabolic syndrome and reducing the risk of CVD [19]. Additionally, it helps mitigate the age-related loss of lean muscle mass, a critical factor in maintaining metabolic health as one ages. The high fibre content of the Mediterranean diet not only aids in blood sugar regulation but also promotes satiety, helping individuals manage their weight more effectively. This reduces the likelihood of obesity-related complications, further highlighting the diet’s role in supporting long-term metabolic health and overall well-being.

2.3. Cognitive Function

Emerging evidence suggests that the Mediterranean diet may also play a protective role in cognitive health. Aging populations are increasingly affected by neurodegenerative diseases such as Alzheimer’s and dementia. A longitudinal study by Nucci et al. found that higher adherence to the Mediterranean diet was associated with a slower rate of cognitive decline and a reduced risk of developing Alzheimer’s disease [20]. In an older Mediterranean population at high cardiovascular risk, improvements in memory function are associated with changes in serum vitamin B12 levels, but only among those who adhere closely to the Mediterranean diet [21]. The diet’s rich content of antioxidants, vitamins, and polyphenols, which are abundant in fruits, vegetables, nuts, and olive oil, is believed to protect against oxidative stress and inflammation, both of which are implicated in the pathogenesis of neurodegenerative diseases [21].

2.4. Longevity

The Mediterranean diet’s impact on longevity has been widely studied, with research indicating that this dietary pattern is associated with a longer lifespan [22,23]. A cohort study by Schwingshackl et al. involving over half a million participants found that greater adherence to the Mediterranean diet was linked to a significantly lower risk of all-cause mortality [22]. The study highlighted that the diet’s comprehensive approach, which includes not only the types of foods consumed but also the emphasis on social interactions during meals, contributes to its beneficial effects on longevity. The Mediterranean diet, though seemingly simple and local, offers extensive health benefits and represents a gold standard in preventive medicine, rooted in a distinctive Mediterranean lifestyle rather than just specific ingredients or methods, resulting in longevity [22].

The Mediterranean diet promotes longevity through multiple mechanisms. Its high content of antioxidants from fruits, vegetables, and olive oil reduces oxidative stress, a key factor in aging. Omega-3 fatty acids from fish and nuts enhance cardiovascular health by lowering triglycerides and improving endothelial function. The diet’s fibre-rich components improve gut microbiota diversity, fostering anti-inflammatory and immune-modulatory effects. Polyphenols and flavonoids regulate gene expression, modulate autophagy, and inhibit cellular senescence. Additionally, this diet supports metabolic homeostasis by improving insulin sensitivity and reducing chronic low-grade inflammation, both of which are crucial for preventing age-related diseases and extending lifespan [23]. Mediterranean diet, highlighting its emphasis on plant-based foods, olive oil, and moderate fish and poultry intake, while limiting red meat and processed foods. It outlines key nutrients, mechanisms (anti-inflammatory, antioxidant, improved lipid and insulin metabolism), and associated health benefits, including cardiovascular protection, metabolic improvements, and longevity support. The table also addresses population suitability, safety considerations, practical and cultural adaptability, environmental impact, and the strong evidence base supporting its effectiveness (

Table 1. Overview of the Mediterranean Diet: Components, Mechanisms, Benefits, and Safety Considerations.

Parameter	Description
Definition	Traditional eating pattern of Mediterranean countries emphasizing plant-based foods, olive oil, moderate fish and poultry, and limited red meat and sweets.
Primary Goal	Promote cardiovascular/metabolic health, reduce chronic disease risk, support longevity.
Core Principles	High intake of fruits, vegetables, whole grains, legumes, nuts, olive oil; moderate consumption of fish and poultry; limited red meat, processed foods, and sweets.
Major Nutrients Emphasized	Monounsaturated fats, fiber, polyphenols, antioxidants, vitamins, minerals.
Restricted Nutrients/Foods	Red and processed meats, refined sugars, ultra-processed foods, and saturated fats.
Mechanisms of Action	Reduces oxidative stress and systemic inflammation; improves lipid metabolism; enhances endothelial function; supports insulin sensitivity.
Health Benefits	Lowers cardiovascular risk, improves metabolic health, reduces incidence of type 2 diabetes, obesity, and neurodegenerative disorders; supports longevity and healthy aging.
Population Suitability	Suitable for general populations; especially beneficial for adults at cardiometabolic risk.
Safety Considerations	Safe; moderate wine intake may not be suitable for all; attention to nutrient balance required when adapted to non-Mediterranean regions.
Practical Limitations	Availability and cost of certain foods outside Mediterranean regions; may require cultural adaptations.
Cultural Adaptability	Adaptable by substituting local nutrient-dense foods while preserving core dietary principles.
Environmental Sustainability	Plant-rich, minimally processed foods support environmental sustainability; moderate environmental impact from fish/poultry consumption.
Evidence Strength	Strong—supported by randomized controlled trials, meta-analyses, and epidemiological studies demonstrating cardiometabolic and longevity benefits.

).

2.5. Environmental Sustainability

In addition to its health benefits, the Mediterranean diet is also considered environmentally sustainable. The Mediterranean diet has a lower environmental impact compared to Western dietary patterns, primarily due to its plant-based focus and lower reliance on red meat [24]. This aspect of the diet aligns with growing global concerns about sustainable food systems and the need to reduce the environmental footprint of dietary choices. The Mediterranean diet stands out as one of the most well-researched and beneficial dietary patterns for promoting health and longevity. Its emphasis on nutrient-dense, minimally processed foods, combined with a balanced intake of healthy fats, makes it a powerful tool for preventing chronic diseases, enhancing metabolic and cognitive health, and supporting environmental sustainability [24]. The wealth of recent research underscores the importance of adopting dietary patterns that are not only health-promoting but also sustainable, making the Mediterranean diet a model for both personal and planetary health [22].

2.6. Regional Variations and Challenges in Adherence

Although the Mediterranean diet originated in countries bordering the Mediterranean Sea, its composition varies across regions due to differences in cultural practices, agricultural availability, and socioeconomic conditions. For example, olive oil is the primary fat source in Southern Europe, whereas Northern Mediterranean regions may rely more on other vegetable oils or animal fats. Similarly, fish and legume consumption differs according to coastal versus inland populations. When adapted globally, local substitutions and limited access to traditional ingredients can alter the diet’s nutritional profile. Modern lifestyles, urbanization, and the increasing prevalence of processed foods also pose challenges to sustained adherence. Furthermore, cost, convenience, and lack of awareness about authentic Mediterranean dietary principles often hinder long-term compliance. Promoting regionally tailored dietary guidelines and education programs could help preserve the diet’s health benefits while accommodating cultural and economic diversity [25].

2.7. Safety and Practical Considerations

From a safety and practical standpoint, the Mediterranean diet is widely regarded as one of the safest and most sustainable dietary models. However, its successful adoption outside the Mediterranean region may be influenced by food availability, cultural eating habits, and economic constraints, as high-quality olive oil, nuts, and fresh produce may be expensive or less accessible in some regions. Additionally, the moderate consumption of wine, which is traditional in Mediterranean cultures, may not be suitable or acceptable for all populations due to cultural, religious, or medical reasons. Adapting the diet with culturally appropriate substitutions, such as replacing wine with antioxidant-rich fruits or juices, can preserve its health benefits. The Mediterranean diet is a balanced, safe, and evidence-based nutritional model that supports cardiovascular and metabolic health. With proper localization and nutritional guidance, it can be effectively integrated into diverse populations as a sustainable approach to disease prevention and longevity [26].

3. The DASH Diet

The Dietary Approaches to Stop Hypertension (DASH) diet is a well-researched dietary pattern that was initially developed to help manage high blood pressure. Over the years, its health benefits have been widely recognized and supported by numerous studies [27,28,29]. This dietary approach also helps reduce LDL cholesterol, a key contributor to heart disease. By focusing on nutrient-rich foods, the DASH diet emphasizes the intake of vegetables, fruits, whole grains, and fat-free or low-fat dairy products. It incorporates sources of lean protein such as fish, poultry, beans, and nuts. The diet is particularly high in potassium, calcium, and magnesium, minerals essential for cardiovascular health. It limits the consumption of sodium (salt), added sugars, and saturated fats, which are prevalent in processed foods and full-fat dairy products [27]. Through these dietary modifications, the DASH diet effectively addresses two major risk factors for CVD: high blood pressure and elevated LDL cholesterol levels. This balanced approach to nutrition not only helps in managing hypertension but also offers a host of other health benefits, making it a valuable dietary model for overall health promotion (Figure 2).

3.1. Hypertension Management

The primary goal of the DASH diet is to reduce blood pressure, which is a major risk factor for CVD. A meta-analysis by Siervo et al. demonstrated that adherence to the DASH diet significantly reduces systolic and diastolic blood pressure, particularly in individuals with hypertension [27]. The high intake of potassium, magnesium, and calcium, which are abundant in the fruits, vegetables, and dairy components of the DASH diet, plays a crucial role in blood pressure regulation. These minerals help balance the negative effects of sodium and improve vascular health [28].

3.2. Cardiovascular Health

Beyond its effects on blood pressure, the DASH diet has been associated with broader cardiovascular benefits. Adherence to the DASH diet is linked to lower mortality rates from cardiovascular causes [2]. The blood pressure-lowering effects of a low-sodium diet and a high-potassium diet are well-documented, particularly among hypertensive individuals. High potassium intake, a central component of the DASH diet, has been linked to a reduced risk of cardiovascular events. Furthermore, research utilizing rigorous measurement techniques has demonstrated significant cardiovascular benefits associated with reduced sodium consumption. The diet’s emphasis on whole grains, lean proteins, and healthy fats from nuts and seeds helps improve lipid profiles, reduce inflammation, and enhance overall heart health. The reduction in red and processed meat consumption also contributes to lower levels of saturated fats and cholesterol, further protecting against CVD [29].

3.3. Metabolic Health

The DASH diet has shown promising results in improving metabolic health, particularly in reducing the risk of type 2 diabetes and managing weight. A study found that individuals following the DASH diet had a lower incidence of type 2 diabetes and better insulin sensitivity [30]. Adopting a DASH diet can lead to rapid improvements in insulin sensitivity, insulin requirements, and related markers in individuals with insulin-treated type 2 diabetes, with more substantial dietary changes yielding greater benefits. The high fibre content from fruits, vegetables, and whole grains aids in regulating blood sugar levels and promoting satiety, which can help prevent overeating and support weight management [31].

3.4. Kidney Health

Emerging evidence suggests that the DASH diet may also benefit kidney health. A study reported that adherence to the DASH diet is associated with a slower progression of chronic kidney disease (CKD) and improved renal function, reduced eGFR over a 4-week period. The diet’s low sodium content, along with its high levels of antioxidants and anti-inflammatory nutrients, helps reduce the strain on the kidneys and prevents further damage. Low adherence to the DASH diet resulted in a greater risk of end-stage renal disease (ESRD) in adults with moderate CKD and hypertension, especially in non-Hispanic blacks and persons having diabetes [32]. The DASH diet is a well-rounded dietary approach that offers a multitude of health benefits. Initially designed to combat hypertension, it has proven effective in improving cardiovascular health, enhancing metabolic function, and supporting kidney health. Recent studies continue to underscore the importance of the DASH diet as a comprehensive strategy for disease prevention and health promotion. By focusing on nutrient-dense, whole foods and limiting sodium and unhealthy fats, the DASH diet provides a sustainable and effective way to improve overall health and well-being [29,31].

3.5. Safety and Practical Considerations

The DASH diet is generally considered safe for most individuals; however, certain considerations must be acknowledged. Individuals with chronic kidney disease or electrolyte imbalances should exercise caution due to the diet’s relatively high intake of potassium and magnesium. Adherence can also be challenging in regions where fresh produce and low-fat dairy are less accessible or cost-prohibitive. Moreover, abrupt reductions in sodium intake may lead to dizziness or fatigue in some individuals, highlighting the need for gradual adjustment and personalized guidance. Therefore, the DASH diet remains a safe, balanced, and adaptable eating pattern that promotes cardiovascular and metabolic health. When implemented with attention to local food availability, cultural preferences, and individual health conditions, it can serve as a sustainable model for long-term dietary modification and disease prevention [33,34].

Table 2. Overview of the DASH Diet: Components, Mechanisms, Benefits, and Safety Considerations.

Parameter	Description
Primary Goal	To lower blood pressure, improve cardiovascular health, and reduce overall chronic disease risk through balanced nutrition.
Core Principles	Emphasizes consumption of fruits, vegetables, whole grains, low-fat dairy, lean proteins (poultry, fish, legumes), and nuts; limits red meat, added sugars, and sodium.
Major Nutrients Emphasized	Potassium, calcium, magnesium, fiber, and unsaturated fatty acids.
Restricted Nutrients	Sodium (recommended < 2300 mg/day, ideally < 1500 mg/day), saturated fats, trans fats, cholesterol, and added sugars.
Typical Daily Pattern	6–8 servings of grains; 4–5 servings of vegetables; 4–5 servings of fruits; 2–3 servings of dairy; 2 or fewer servings of lean meat/poultry/fish; 4–5 servings of nuts/legumes per week.
Mechanisms of Action	Improves endothelial function and vascular tone; reduces oxidative stress and systemic inflammation; enhances sodium–potassium balance; promotes insulin sensitivity and lipid regulation.
Health Benefits	Reduces systolic and diastolic blood pressure Lowers LDL cholesterol and improves lipid profiles Decreases risk of stroke, heart failure, and type 2 diabetes Supports weight management and metabolic health
Population Suitability	Suitable for hypertensive, prehypertensive, obese, and metabolically at-risk individuals; adaptable for general populations seeking balanced nutrition.
Safety Considerations	Generally safe; however, high potassium or magnesium intake may need monitoring in individuals with chronic kidney disease or those on potassium-sparing medications.
Practical Limitations	Requires access to fresh produce and low-fat dairy; adherence may be challenging due to cost, taste preferences, or limited availability of recommended foods in some regions.
Cultural Adaptability	Highly adaptable; traditional cuisines can incorporate DASH principles by modifying local dishes to reduce sodium and include more plant-based, fiber-rich foods.
Environmental Sustainability	Supports sustainable eating by promoting plant-based and minimally processed foods, though the inclusion of dairy and meat may have moderate environmental impacts.
Evidence Strength	Strong and is well supported by multiple randomized controlled trials and meta-analyses demonstrating consistent cardiovascular and metabolic benefits.

outlines the DASH diet, emphasizing fruits, vegetables, whole grains, lean protein, and low-fat dairy while limiting sodium, red meat, and added sugars. It highlights mechanisms like blood pressure reduction, improved lipid and insulin metabolism, and cardiovascular protection. The table also covers health benefits, safety considerations, adherence challenges, population suitability, and the strong evidence supporting its role in chronic disease prevention (Table 2).

4. Plant-Based Diets

Plant-based diets are gaining attention as they primarily focus on the consumption of fruits, vegetables, legumes, nuts, seeds, and whole grains while minimizing or excluding animal products. They have garnered significant attention in recent years for their potential health benefits. This dietary approach, which encompasses both vegetarian and vegan regimens, has been associated with reduced risks of chronic diseases, improved overall health, and increased longevity. Recent studies have further elucidated the positive impact of plant-based diets on various aspects of health [35,36] (Figure 3). Furthermore,

Table 3. Overview of Plant-Based Diets: Components, Mechanisms, Benefits, and Safety Considerations.

Parameter	Description
Definition	Diets emphasizing plant-derived foods: fruits, vegetables, whole grains, legumes, nuts, and seeds while reducing or excluding animal-based products. Includes vegetarian, vegan, and flexitarian patterns.
Primary Goal	To promote health, longevity, and sustainability through nutrient-rich, minimally processed plant foods and reduced intake of animal fats and processed meats.
Core Principles	High consumption of fiber, phytonutrients, and antioxidants; minimal intake of animal-derived saturated fats and cholesterol; emphasis on whole, unprocessed foods.
Major Nutrients Emphasized	Complex carbohydrates, unsaturated fats (especially omega-6 fatty acids), plant-based proteins, vitamins C and E, polyphenols, and dietary fiber.
Restricted Nutrients/Foods	Red and processed meats, refined grains, added sugars, saturated fats, and ultra-processed foods.
Mechanisms of Action	Reduces systemic inflammation and oxidative stress Improves gut microbiota diversity and metabolic function Enhances endothelial function and lipid metabolism Lowers insulin resistance and chronic disease biomarkers
Health Benefits	Reduces risk of cardiovascular disease, obesity, type 2 diabetes, and certain cancers Improves lipid profile and glycemic control Promotes weight management and longevity
Population Suitability	Suitable for the general population, particularly for individuals with cardiovascular or metabolic risk; requires proper planning for vulnerable groups (children, pregnant women, elderly).
Safety Considerations	Possible deficiencies in vitamin B12, vitamin D, calcium, iron, zinc, iodine, and omega-3 fatty acids in poorly planned vegan diets; requires supplementation or fortified foods.
Practical Limitations	May be challenging in regions with limited access to diverse plant protein sources or fortified foods; higher fiber intake may cause initial gastrointestinal discomfort.
Cultural Adaptability	Highly adaptable across global cuisines; traditional legumes, grains, and vegetables can be incorporated to meet nutritional needs while respecting local dietary habits.
Environmental Sustainability	Strongly sustainable low carbon footprint, minimal water use, and reduced environmental degradation compared to animal-based diets.
Evidence Strength	Strong—supported by large cohort studies and meta-analyses showing consistent associations with reduced chronic disease and mortality rates.

summarizes plant-based diets, focusing on fruits, vegetables, legumes, whole grains, nuts, and seeds while minimizing or excluding animal products. It highlights mechanisms such as reduced inflammation, improved lipid and glucose metabolism, and gut microbiota modulation. The table also covers health benefits, potential nutrient deficiencies (B12, iron, omega-3), safety considerations, population suitability, and strategies to ensure balanced nutrition (Table 3).

4.1. Cardiovascular Health

One of the well-documented benefits of plant-based diets is their positive effect on cardiovascular health. A meta-analysis on plant-based diets is associated with a significantly lower risk of CVD compared to omnivorous diets [37]. Plant-based diets appear beneficial in reducing cardiometabolic risk factors, as well as CVDs, cancer risk and mortality. The study by Ornish et al. demonstrated that intensive lifestyle changes, including a low-fat, plant-based diet, regular exercise, stress management, and smoking cessation, significantly reversed atherosclerotic blockages in coronary arteries [38]. Unlike other dietary interventions, this approach showed measurable regression of coronary artery disease over one year, as evidenced by improved coronary artery stenosis and reduced cardiac events, highlighting the unique effectiveness of plant-based interventions in reversing atherosclerosis [38]. The high intake of fiber, antioxidants, and healthy fats from plant sources helps improve lipid profiles, reduce blood pressure, and decrease inflammation. These factors collectively contribute to a lower risk of developing conditions such as coronary artery disease and stroke [38].

4.2. Type 2 Diabetes Management

Type 2 diabetes is a chronic metabolic condition characterized by insulin resistance and inadequate insulin production, leading to elevated blood glucose levels. Its prevalence is increasing globally, largely due to rising obesity rates and the adoption of Western diets. Research indicates that substituting animal-based foods with healthful plant-based foods is associated with a reduced risk of type 2 diabetes [39]. Randomized controlled trials have shown that replacing animal foods with healthy plant foods leads to notable cardio-metabolic improvements in individuals with type 2 diabetes or those at high risk for the condition [40,41]. Dietary patterns that limit or exclude animal foods in favour of plant-based options, such as fruits, vegetables, whole grains, nuts, and legumes, are consistently linked with a lower risk of type 2 diabetes [40]. Therefore, dietary choices significantly influence insulin resistance, particularly in an aging and increasingly sedentary population. The rising consumption of calorie-dense foods, such as fast foods, meats, animal fats, highly refined grains, and sugar-sweetened beverages, is believed to be a major factor in the escalating rates of type 2 diabetes globally [41].

4.3. Cancer Prevention

Emerging evidence suggests that plant-based diets may play a role in cancer prevention. A study by Liu et al. reviewed the relationship between plant-based diets and cancer risk, finding that such diets are associated with a lower risk of various cancers, including colorectal, breast, and prostate cancer [42]. Better adherence to overall and healthful plant-based diets is associated with a lower risk of cancer. The diet’s rich content of phytochemicals, vitamins, and minerals, combined with its low levels of saturated fats and processed foods, contributes to its cancer-protective effects by reducing oxidative stress and inflammation [43].

4.4. Longevity

With the global increase in centenarians due to enhanced living standards and improved access to quality healthcare, it is increasingly pertinent for lifestyle medicine practitioners to focus on modifiable health behaviours to enhance quality of life. Preventing chronic diseases that contribute to premature mortality not only extends lifespan but also improves the quality of life. Plant-based diet is fundamental to achieving healthy longevity and may serve as a crucial prescriptive tool for promoting both extended lifespan and superior quality of life in aging populations [44]. Plant-based diets have also been linked to increased longevity. A large cohort study by Orlich et al. found that individuals adhering to plant-based diets had a lower risk of mortality from all causes compared to those following omnivorous diets [44]. The diet’s emphasis on nutrient-dense foods, coupled with its lower calorie density, helps maintain a healthy weight and reduces the risk of chronic diseases, contributing to a longer and healthier life.

4.5. Environmental and Ethical Considerations

In addition to health benefits, plant-based diets are often promoted for their environmental and ethical advantages. The study by Bunge et al. analysed the sustainability benefits of shifting from current diets in Sweden to plant-based or whole-food diets. It found that such transitions could significantly reduce environmental impacts, including greenhouse gas emissions, land use, and water consumption, while supporting public health goals, emphasizing the dual benefits of dietary changes for sustainability and health [45]. These aspects align with growing concerns about sustainable food systems and animal welfare. Plant-based diets offer substantial health benefits, including improved cardiovascular health, better management of type 2 diabetes, reduced cancer risk, and increased longevity [36]. Additionally, their environmental and ethical considerations further underscore the value of adopting such dietary patterns for a healthier and more sustainable future.

4.6. Potential Nutrient Deficiencies in Plant-Based Diets

While plant-based diets are rich in fruits, vegetables, legumes, whole grains, nuts, and seeds, they offer numerous health benefits, including reduced risk of cardiovascular disease, obesity, and type 2 diabetes. They may also pose certain nutritional challenges. Key potential deficiencies include vitamin B12, iron, zinc, calcium, iodine, and omega-3 fatty acids, as these nutrients are predominantly found in animal-based foods [46]. Vitamin B12 is critical for red blood cell formation and neurological function. B12 deficiency is common in strict vegans. Strategies include fortified foods (e.g., plant-based milks, breakfast cereals), nutritional yeast, or B12 supplementation. Plant-derived (non-heme) iron has lower bioavailability than heme iron from animal sources. Combining iron-rich foods (lentils, beans, spinach) with vitamin C-rich foods (citrus fruits, bell peppers) enhances absorption.

Calcium and Vitamin D are essential for bone health. They can be obtained from fortified plant milks, tofu, almonds, and exposure to sunlight for vitamin D. Omega-3 Fatty Acid is found in flaxseeds, chia seeds, hemp seeds, and walnuts, but conversion to active EPA and DHA forms is limited. Algal oil supplements can provide direct DHA/EPA. Whole grains, legumes, nuts, and seeds can supply zinc, though absorption may be hindered by phytates; iodine can be obtained from iodized salt or seaweed (in moderation). Cultural acceptability, food availability, and socioeconomic factors also influence adherence and feasibility [46]. In some regions, access to diverse plant protein sources or fortified alternatives may be limited. Therefore, personalized dietary counseling is essential to maintain nutritional adequacy while ensuring sustainability and long-term adherence. Overall, well-planned plant-based diets are safe, health-promoting, and environmentally sustainable when tailored to individual needs and local food contexts [46].

5. The Blue Zones Diet

The Blue Zones diet, Food Secrets of the World’s Longest-Lived People, inspired by the eating habits of populations in regions known for exceptional longevity and low rates of chronic diseases, offers a compelling model for promoting health and extending lifespan. The term “Blue Zones” refers to specific areas where people live significantly longer, healthier lives compared to the global average. Figure 4 illustrates the Blue Zone Diet, highlighting five key regions, Okinawa (Japan), Ikaria (Greece), Nicoya Peninsula (Costa Rica), Loma Linda (California, USA), and Sardinia (Italy), where people are known for exceptional longevity. The dietary principles common to these regions emphasize plant-based foods, particularly fruits, vegetables, whole grains, nuts, and seeds, with moderate consumption of animal products. Additionally, the diet promotes minimal use of added sugars and salt and discourages processed foods [47]. Overall, it represents a nutrient-dense, whole-food approach strongly associated with increased lifespan and better metabolic health (Figure 4).

5.1. Plant-Based Focus

The phenomenon of increased longevity observed in certain populations is a relatively recent area of study, with research intensifying over the past two decades to uncover the factors contributing to their extended lifespan and to explore potential insights for broader application. Among the various characteristics of these long-lived populations, their dietary habits are particularly notable due to their quantifiable nature and potential for wider applicability. However, it is often assumed that the presence of specific dietary practices in these populations directly contributes to their longevity. This assumption requires rigorous investigation to establish a causal relationship between diet and extended lifespan. One of the core principles of the Blue Zones diet is its emphasis on plant-based foods. A study by Chen et al. found that diets rich in fruits, vegetables, legumes, nuts, and whole grains, which are central to the Blue Zones diet, are associated with a lower risk of CVD and improved longevity [47]. These foods are high in essential nutrients, antioxidants, and fibre, which contribute to overall health by reducing inflammation, improving metabolic function, and supporting cardiovascular health [48].

5.2. Low Animal Product Consumption

While predominantly plant-based, the Blue Zones diet includes moderate consumption of animal products, primarily fish and dairy, and very limited red meat. Research highlighted that moderate intake of fish, as seen in Blue Zones regions, is linked to reduced mortality rates and improved cardiovascular health due to the presence of omega-3 fatty acids and lean protein [49]. Similarly, limited dairy consumption, which is a characteristic of the Blue Zones diet, can be beneficial for bone health and longevity. Some populations, like Loma Linda, completely avoid animal products. Adjustments are consistent with Blue Zones guidelines [50].

5.3. Social and Lifestyle Factors

The Blue Zones diet is not just about food but also incorporates social and lifestyle factors that contribute to health and longevity. The concept of “Ikigai” in Okinawa and the emphasis on family and community in Sardinia play a significant role in mental and emotional well-being. A study found that strong social connections and regular physical activity, common in Blue Zones, are associated with improved cognitive function and reduced risk of dementia [51]. Additionally, the practices of mindful eating and maintaining a purpose-driven life are integral to the Blue Zones lifestyle [51].

5.4. Longevity and Health Benefits

A study found that adherence to Blue Zones dietary patterns is linked to a lower incidence of chronic diseases such as diabetes, cancer, and cardiovascular diseases, contributing to an extended lifespan and enhanced quality of life [52]. Therefore, the Blue Zones diet offers a holistic approach to achieving optimal health and longevity. By emphasizing plant-based foods, moderate consumption of animal products, and incorporating key social and lifestyle factors, the Blue Zones diet provides a comprehensive model for promoting a longer, healthier life. Studies continue to validate the principles of this diet, highlighting its effectiveness in reducing chronic disease risk and supporting overall well-being [51,52].

5.5. Transferability of Blue Zones Principles to Other Populations:

Blue zone diets provide valuable insights, but their transferability to other populations requires critical assessment. Cultural, socioeconomic, environmental, and genetic factors may limit direct adoption; for example, dietary staples and social structures differ significantly across regions, affecting feasibility and adherence. Additionally, modern urban lifestyles, work patterns, and food environments may impede the replication of daily physical activity, communal eating, and stress-reducing practices characteristic of Blue Zones. Therefore, while the core principles of balanced nutrition, social engagement, physical activity, and purpose are broadly beneficial, adaptation strategies must consider local context, accessibility, and cultural acceptability to achieve meaningful health outcomes [53].

5.6. The Blue Zones Diet: Safety and Practical Considerations

The Blue Zones diet emphasizes predominantly plant-based foods, whole grains, legumes, fruits, vegetables, nuts, and limited portions of fish or dairy while minimizing processed foods, red meat, and added sugars. It is generally regarded as safe, nutrient-dense, and sustainable, providing an abundance of fiber, antioxidants, and phytochemicals that support cardiovascular, metabolic, and cognitive health [53]. However, certain practical and safety considerations should be acknowledged. Strict adherence to a highly plant-based pattern may lead to insufficient intake of vitamin B12, iron, or omega-3 fatty acids if not properly planned, especially in individuals with limited dietary diversity. Cultural and regional differences may also pose challenges in replicating traditional Blue Zones foods, such as specific legumes or fermented products, which contribute to their health benefits.

Additionally, the naturally low caloric intake characteristic of these regions might not meet the energy requirements of all individuals, particularly those with higher metabolic demands. While the Blue Zones diet exemplifies a holistic and sustainable model for healthy aging, its safe implementation in other populations should include appropriate nutrient monitoring, cultural adaptation, and dietary education to ensure balanced nutrition and long-term adherence [53].

Table 4. Overview of the Blue Zones Diet: Components, Mechanisms, Benefits, and Safety Considerations.

Parameter	Description
Definition	Diet modelled after the traditional eating patterns of regions with exceptional longevity, including Okinawa (Japan), Sardinia (Italy), Ikaria (Greece), Nicoya (Costa Rica), and Loma Linda (California).
Primary Goal	To promote longevity and healthy aging through predominantly plant-based, minimally processed foods, and lifestyle integration.
Core Principles	High intake of legumes, whole grains, vegetables, fruits, nuts, and moderate consumption of fish or dairy; limited red meat, processed foods, and added sugars; occasional small portions of wine in some regions.
Major Nutrients Emphasized	Fiber, antioxidants, polyphenols, plant proteins, omega-3 fatty acids (from fish), vitamins, and minerals.
Restricted Nutrients/Foods	Red and processed meats, refined sugars, ultra-processed foods, and excess saturated fats.
Mechanisms of Action	Reduces oxidative stress and systemic inflammation Improves gut microbiota diversity Supports healthy metabolic and cardiovascular profiles Promotes calorie moderation and hormetic stress responses
Health Benefits	Lower risk of cardiovascular disease, metabolic syndrome, obesity, and certain cancers Enhanced cognitive health and reduced dementia risk Supports healthy body weight and longevity
Population Suitability	Suitable for general populations; particularly beneficial for middle-aged and older adults; requires planning for nutrient adequacy in strict plant-based implementations.
Safety Considerations	Generally safe and nutrient-dense, but may require supplementation or monitoring for vitamin B12, iron, calcium, and omega-3 fatty acids in highly plant-based variants.
Practical Limitations	Some traditional foods may be region-specific and not widely available; strict adherence may require cultural adaptation and dietary education.
Cultural Adaptability	Adaptable through local plant-based foods while maintaining key principles of low processed foods, high legumes, and plant diversity.
Environmental Sustainability	Highly sustainable due to emphasis on plant-based and minimally processed foods, low environmental impact, and local sourcing.
Evidence Strength	Moderate—based primarily on observational studies, population cohorts, and epidemiological data from longevity hotspots.

summarizes the Blue Zones diet, based on traditional eating patterns from regions with exceptional longevity. It emphasizes plant-based, minimally processed foods, legumes, whole grains, and moderate fish or dairy, promoting longevity through anti-inflammatory, antioxidant, and gut microbiota–modulating mechanisms. The table outlines health benefits, population suitability, safety considerations, practical and cultural adaptability, environmental sustainability, and the moderate evidence base from observational and epidemiological studies (Table 4).

6. Intermittent Fasting

Intermittent fasting has emerged as a popular dietary strategy that alternates between periods of eating and fasting. Unlike traditional calorie-restriction diets, which focus on reducing overall calorie intake, intermittent fasting emphasizes the timing of food intake. This approach has garnered significant attention for its potential benefits in enhancing metabolic health, promoting weight loss, and extending lifespan. Research has provided valuable insights into the efficacy of intermittent fasting and its impact on various aspects of health [54] (Figure 5).

Table 5. Overview of Intermittent Fasting: Patterns, Mechanisms, Benefits, and Safety Considerations.

Parameter	Description
Definition	Eating pattern that alternates between periods of fasting and feeding, without prescribing specific food types. Includes time-restricted feeding (e.g., 16:8), alternate-day fasting, and periodic fasting.
Primary Goal	To improve metabolic health, support weight management, and potentially enhance longevity by leveraging periods of caloric restriction.
Core Principles	Structured fasting windows (e.g., 12–20 h) interspersed with defined eating periods; focus on nutrient-dense foods during feeding periods; avoidance of excessive caloric intake post-fast.
Major Nutrients Emphasized	Balanced intake of proteins, complex carbohydrates, healthy fats, fiber, vitamins, and minerals during eating windows; hydration maintained throughout fasting periods.
Restricted Nutrients/Foods	No specific restrictions, but overconsumption of processed or high-calorie foods during eating periods can negate benefits.
Mechanisms of Action	Enhances autophagy and cellular repair Reduces oxidative stress and systemic inflammation Improves insulin sensitivity and glucose metabolism Supports weight loss and favorable lipid profiles May influence circadian rhythm and hormonal regulation
Health Benefits	Reduces risk of obesity, type 2 diabetes, and cardiovascular disease Supports metabolic flexibility and fat oxidation Potentially extends lifespan and delays age-related diseases (based on preclinical and emerging human data)
Population Suitability	Suitable for healthy adults; may be adapted for overweight or metabolic syndrome patients under supervision. Not recommended for pregnant women, children, elderly with frailty, or individuals with eating disorders without professional guidance.
Safety Considerations	Potential risks include hypoglycemia, dehydration, fatigue, dizziness, or nutrient deficiencies if fasting is prolonged or poorly planned. Medical supervision is advised for individuals with chronic diseases or on medications.
Practical Limitations	Adherence can be challenging due to social, cultural, or work-related meal schedules; requires education on timing, food quality, and hydration.
Cultural Adaptability	Highly adaptable since no specific foods are mandated; fasting windows can align with local meal patterns and lifestyle.
Environmental Sustainability	Indirectly promotes sustainability by potentially reducing overall food intake and minimizing overconsumption, though impact depends on food choices during eating periods.
Evidence Strength	Emerging but growing—supported by preclinical studies, randomized controlled trials, and observational studies, particularly for metabolic and cardiometabolic outcomes.

summarizes intermittent fasting, highlighting structured fasting feeding patterns such as time-restricted and alternate-day fasting. It emphasizes metabolic, weight management, and longevity benefits through mechanisms like autophagy, improved insulin sensitivity, and reduced inflammation, with health benefits, population suitability, safety considerations, adherence challenges, cultural adaptability, environmental impact, and the emerging evidence supporting its effectiveness (Table 5).

6.1. Mechanism of Action

Intermittent fasting encompasses several methods, including the 16/8 method, where individuals fast for 16 h and eat within an 8-h window; the 5:2 method, which involves eating normally for five days and restricting calories on two non-consecutive days; and alternate-day fasting, where individuals alternate between days of regular eating and days of fasting. These methods are designed to create periods of low energy intake, which can stimulate metabolic processes that promote health [55].

6.2. Metabolic Health

Intermittent fasting is a modern dietary approach rooted in ancient traditions, which involves alternating cycles of fasting or calorie restriction with periods of eating. This method enhances the body’s resilience to stress and its benefits are further increased when combined with exercise. It has been shown to influence various pathological conditions, including cancer, obesity, diabetes, CVD, and neurodegenerative disorders [54]. One of the primary benefits of intermittent fasting is its positive effect on metabolic health. Intermittent fasting improves insulin sensitivity and reduces the risk of type 2 diabetes by decreasing insulin levels and enhancing glucose regulation [55]. The fasting periods induce metabolic switching, where the body shifts from using glucose to burning fat for energy, which can lead to weight loss and improved metabolic markers [55].

6.3. Weight Management

Intermittent fasting has been shown to be effective in promoting weight loss and managing obesity. A systematic review and meta-analysis by Harvie et al. found that intermittent fasting resulted in significant reductions in body weight, body fat, and waist circumference compared to continuous calorie restriction [56]. The recent surge in the popularity of Time Restricted Eating (TRE) can be attributed to its simplicity and the absence of calorie counting for weight loss. This aspect of TRE may particularly attract individuals with obesity, potentially leading to lasting improvements in metabolic health. The restricted eating windows reduce the overall calorie intake and enhance fat oxidation, contributing to effective weight management [57].

6.4. Cardiovascular Health

Cardiovascular health is another area where intermittent fasting has shown promise. A study by Tinsley and La Bounty reported that intermittent fasting can lead to improvements in blood lipid profiles, including reductions in total cholesterol, LDL cholesterol, and triglycerides, which are risk factors for cardiovascular diseases [58]. The diet’s effects on reducing inflammation and oxidative stress also contribute to cardiovascular health. Intermittent fasting has been demonstrated to reduce weight and alleviate obesity-related complications. This clinical and experimental study examined the effects of Intermittent fasting on the lipid profile, white adipose tissue (WAT) dynamics, and the gut microbiome. Notably, IF corrects dyslipidemia, reduces WAT accumulation, and decreases inflammation, thereby lowering the risk of CVD and obesity [59].

6.5. Longevity

Intermittent fasting can protect various organs from disease, with substantial evidence indicating that this dietary approach can prevent, and potentially reverse, chronic conditions such as heart disease, type II diabetes, and age-related neurological disorders. Research has found that these benefits may be linked to molecular changes occurring in multiple organs throughout the body [60]. A study by Mattson et al. found that intermittent fasting might extend lifespan by improving cellular stress resistance and promoting autophagy, a process that removes damaged cells and supports cellular repair. The findings indicate that intermittent fasting may help delay the onset of age-related diseases and enhance overall lifespan [60].

6.6. Cognitive Health

Emerging evidence also suggests that intermittent fasting can benefit cognitive health. A study by Gudden et al. found that intermittent fasting improves brain function and reduces the risk of neurodegenerative diseases by enhancing brain plasticity and reducing oxidative stress [61]. These observations lead to a hypothesis that intermittent fasting over the years will potentially reverse or delay the pathological process in Alzheimer’s disease. The fasting periods may promote the production of brain-derived neurotrophic factor (BDNF), a protein associated with cognitive function and neuro-protection [62].

6.7. Safety and Practical Considerations

While intermittent fasting offers numerous benefits, it is important to consider individual health conditions and lifestyle factors. Some individuals may experience adverse effects, such as fatigue or nutrient deficiencies, especially if the fasting periods are not managed properly. A study by Varady et al. emphasized the importance of ensuring adequate nutrient intake during eating windows and consulting healthcare professionals before starting intermittent fasting, particularly for individuals with pre-existing health conditions [63]. However, these approaches may not be safe for everyone and should be approached with caution.

Safety concerns include hypoglycemia, nutrient deficiencies, dehydration, electrolyte imbalances, fatigue, and, in some cases, disordered eating patterns. Contraindications include pregnancy and lactation, childhood and adolescence, eating disorders, uncontrolled diabetes, chronic illnesses, and frailty in older adults. Medical supervision is recommended, particularly for individuals with underlying health conditions or those taking medications that affect blood glucose, blood pressure, or metabolism. Tailoring fasting schedules, monitoring biomarkers, and ensuring adequate nutrient intake are essential to minimize risks and optimize benefits. Intermittent fasting represents a promising dietary approach with significant potential to enhance metabolic health, support weight management, improve cardiovascular health, and potentially extend lifespan. As research continues to evolve, intermittent fasting may become a more widely accepted strategy for promoting overall health and longevity [60].

7. Caloric Restriction

Caloric restriction (CR) involves reducing calorie intake without malnutrition, and it has a potential benefit on health and longevity. Unlike intermittent fasting or specific dietary patterns, CR focuses on reducing the total caloric intake over an extended period. This dietary approach has been linked to numerous health benefits, including improved metabolic health, extended lifespan, and reduced risk of age-related diseases [64] (Figure 6).

7.1. Metabolic Health

CR has emerged as a powerful strategy for enhancing metabolic health, offering significant benefits in the prevention and management of metabolic syndrome and associated diseases. One of the most notable impacts of CR is its ability to improve insulin sensitivity, a critical factor in preventing type 2 diabetes. Insulin sensitivity refers to how effectively the body’s cells respond to insulin, allowing for efficient glucose uptake and utilization. In individuals with impaired insulin sensitivity, the risk of developing type 2 diabetes is markedly increased. A study conducted by Johnson et al. demonstrated that CR effectively enhances insulin sensitivity, thereby reducing the likelihood of glucose dysregulation and diabetes onset [64]. Moreover, CR has been shown to reduce markers of inflammation, which are closely linked to the development of insulin resistance and other metabolic disorders.

Chronic inflammation, often driven by poor dietary habits and excess calorie intake, plays a pivotal role in the progression of metabolic syndrome, characterized by a cluster of conditions such as elevated blood pressure, high blood sugar, abnormal cholesterol levels, and excess body fat around the waist. Participants in the Johnson et al. study who adhered to a CR regimen also exhibited significant improvements in glucose metabolism and lipid profiles. These changes underscore CR’s potential to lower the risk of metabolic syndrome, cardiovascular disease, and other related health issues. By optimizing insulin sensitivity and reducing inflammation, caloric restriction offers a promising approach to improving metabolic health and extending lifespan [64].

7.2. Longevity

Caloric restriction has been associated with increased lifespan. Research by Dorling et al. reviewed these findings and discussed the potential for CR to extend lifespan and delay the onset of age-related diseases in humans [65]. Although direct evidence in humans is still emerging, long-term studies in non-human primates have shown promising results, suggesting that CR can contribute to healthier aging and longevity [65,66,67].

7.3. Cardiovascular Health

CR has demonstrated notable benefits for cardiovascular health. A randomized controlled trial conducted by Chen et al. found that CR significantly improves key cardiovascular markers, including blood pressure, cholesterol levels, and arterial stiffness [66]. The study highlighted that through these improvements, CR effectively reduces cardiovascular risk factors, thereby potentially lowering the incidence of heart disease and stroke. This finding underscores the significant positive impact of CR on overall cardiovascular health. By mitigating critical risk factors, CR presents a promising strategy for the prevention and management of cardiovascular diseases, supporting a healthier, longer lifespan through improved heart health [66].

7.4. Cellular and Molecular Mechanisms

CR influences numerous cellular and molecular pathways, significantly contributing to its health benefits. Flanagan et al. demonstrated that CR activates autophagy, a crucial process that eliminates damaged cells and proteins, thereby enhancing cellular repair mechanisms [67]. This activation supports the maintenance of cellular integrity and function. Additionally, CR modulates key signaling pathways, including those involving sirtuins and mTOR, which are vital for regulating aging, stress resistance, and metabolism. These pathways play essential roles in promoting longevity and protecting against age-related diseases. By affecting these cellular processes, CR helps improve overall health, reduce the risk of chronic diseases, and extend lifespan, making it a valuable strategy for enhancing metabolic health and promoting healthy aging [66,67].

7.5. Weight Management

CR is a highly effective approach to weight management, focusing on reducing calorie intake while maintaining nutritional balance. This method primarily targets body fat reduction, which is essential for improving overall health and preventing obesity-related conditions. A study demonstrated that CR significantly decreases both body weight and fat mass, while crucially preserving lean muscle mass. Preserving muscle mass is vital as it supports metabolic function, enhances physical strength, and contributes to long-term health and vitality [68]. CR works by creating a calorie deficit, prompting the body to utilize stored fat as an energy source. This process not only leads to fat loss but also results in improved body composition, characterized by a higher muscle-to-fat ratio. Such changes in body composition have far-reaching benefits, including enhanced metabolic health, improved insulin sensitivity, and a lower risk of developing chronic diseases such as type 2 diabetes, CVD, and certain cancers. Moreover, the benefits of CR extend beyond mere weight loss. By reducing fat mass and improving metabolic markers, CR contributes to better overall health and increased longevity [68]. This makes CR a promising strategy not only for achieving and maintaining a healthy weight but also for supporting long-term physical health and well-being.

7.6. Safety and Practical Considerations

While caloric restriction offers numerous benefits, it is important to approach it with caution. A study noted that extreme CR or poorly managed CR can lead to nutrient deficiencies and other health issues, including decreased bone density and weakened immune function [69]. It is crucial to ensure that CR is implemented in a balanced manner, with adequate nutrient intake and regular medical supervision. CR remains a powerful tool for enhancing health and longevity, with benefits extending to metabolic health, cardiovascular function, and weight management. Recent studies continue to validate the positive effects of CR and provide insights into its mechanisms. However, it is essential to adopt CR thoughtfully, ensuring a balanced approach to avoid potential health risks [68,69].

Table 6. Overview of Caloric Restriction: Components, Mechanisms, Benefits, and Safety Considerations.

Parameter	Description
Definition	A dietary regimen that reduces overall caloric intake without causing malnutrition, typically by 20–40% below usual ad libitum intake, while maintaining adequate macro- and micronutrients.
Primary Goal	To extend lifespan, improve metabolic health, and delay the onset of age-related diseases through controlled energy restriction.
Core Principles	Sustained reduction in daily caloric intake with balanced nutrient composition; emphasis on nutrient-dense foods to meet vitamin and mineral requirements.
Major Nutrients Emphasized	Adequate protein, vitamins, minerals, antioxidants, fiber, and essential fatty acids to prevent malnutrition.
Restricted Nutrients/Foods	Overall caloric intake is reduced; no specific food groups are strictly excluded, but high-calorie, low-nutrient foods are minimized.
Mechanisms of Action	Reduces oxidative stress and systemic inflammation Enhances autophagy and cellular repair processes Improves insulin sensitivity and glucose metabolism Modulates hormonal pathways including IGF-1 and mTOR Promotes favorable lipid metabolism and endothelial function
Health Benefits	Delays onset of age-related diseases (cardiovascular disease, diabetes, cancer) Supports weight management and metabolic health Potentially extends lifespan (evidence mainly from animal studies; emerging human data)
Population Suitability	Primarily studied in healthy adults; not recommended for children, pregnant or lactating women, elderly with frailty or individuals with eating disorders unless carefully supervised.
Safety Considerations	Risk of nutrient deficiencies, loss of lean body mass, fatigue, or decreased bone density if caloric reduction is excessive or nutrient intake is inadequate; requires monitoring by nutrition professional.
Practical Limitations	Long-term adherence is challenging due to hunger, social meal patterns, and lifestyle demands; requires careful meal planning to maintain nutritional adequacy.
Cultural Adaptability	Adaptable across cultures by adjusting portion sizes and selecting locally available nutrient-dense foods.
Environmental Sustainability	Potentially positive, as reduced overall food consumption may lower environmental impact, though depends on food choices.
Evidence Strength	Strong in animal models for lifespan extension; moderate in humans for metabolic and cardiometabolic benefits, with long-term trials ongoing.

summarizes caloric restriction, which involves consistently reducing daily caloric intake without malnutrition. It highlights mechanisms such as decreased oxidative stress, improved insulin sensitivity, enhanced autophagy, and modulation of metabolic and hormonal pathways. It also outlines health benefits, including longevity promotion, cardiometabolic improvements, and reduced age-related disease risk, along with population suitability, safety considerations, practical limitations, and the strong evidence supporting its effects from both preclinical and human studies (Table 6).

8. The Nordic Diet

The Nordic diet, inspired by the traditional eating patterns of the Nordic countries like Denmark, Finland, Iceland, Norway, and Sweden, has gained increasing recognition for its health-promoting and environmentally sustainable characteristics. Rooted in the consumption of locally sourced, seasonal, and minimally processed foods, this dietary model reflects a balance between nutritional adequacy and ecological responsibility. Similar in spirit to the Mediterranean diet, the Nordic diet emphasizes nutrient-rich foods that contribute to overall metabolic and cardiovascular health [70]. The core components of the Nordic diet include whole grains such as oats, rye, and barley; fish, especially fatty varieties rich in omega-3 fatty acids like salmon, herring, and mackerel; root vegetables such as carrots, beets, and potatoes; berries like bilberries and cloudberries that are abundant in antioxidants and legumes and pulses that serve as important sources of plant-based protein. The diet also incorporates low-fat dairy products and lean meats in moderate amounts, while discouraging excessive intake of red and processed meats.

A key feature of this dietary approach is the limited use of added sugars and refined foods, promoting better glycaemic control and reduced risk of chronic diseases [70].

Table 7. Overview of the Nordic Diet: Components, Mechanisms, Benefits, and Safety Considerations.

Parameter	Description
Definition	Diet inspired by traditional eating habits of Nordic countries (Denmark, Finland, Iceland, Norway, Sweden), emphasizing locally sourced and seasonal foods.
Primary Goal	To improve cardiovascular and metabolic health, support longevity, and promote sustainable eating patterns.
Core Principles	High intake of whole grains (rye, oats, barley), root vegetables, berries, legumes, fatty fish (rich in omega-3), low-fat dairy, and rapeseed oil; minimal processed foods, sugar, and red meat.
Major Nutrients Emphasized	Fiber, antioxidants, polyunsaturated and monounsaturated fats, plant proteins, omega-3 fatty acids, vitamins, and minerals.
Restricted Nutrients/Foods	Processed foods, refined sugars, red and processed meats, and excess saturated fats.
Mechanisms of Action	Reduces systemic inflammation and oxidative stress Improves lipid profile and endothelial function Enhances insulin sensitivity and metabolic regulation Supports gut microbiota diversity through fiber-rich foods
Health Benefits	Lowers blood pressure and LDL cholesterol Reduces risk of cardiovascular disease and type 2 diabetes Supports weight management and kidney function Associated with improved overall longevity
Population Suitability	Suitable for general populations, particularly those at risk of cardiovascular and metabolic disorders; adaptable across diverse age groups.
Safety Considerations	Generally safe; individuals with fish or dairy allergies need careful substitutions; high fiber intake may cause mild gastrointestinal discomfort initially.
Practical Limitations	Availability and cost of certain Nordic ingredients (berries, fatty fish, rapeseed oil) may limit adherence outside Northern Europe; requires cultural adaptation.
Cultural Adaptability	Highly adaptable; local seasonal vegetables, whole grains, and fish can substitute traditional Nordic foods while maintaining dietary principles.
Environmental Sustainability	Promotes sustainable eating through local, seasonal, and plant-rich foods; reduced reliance on red meat lowers environmental impact.
Evidence Strength	Moderate to strong—supported by cohort studies and randomized trials demonstrating cardiometabolic benefits and improved mortality outcomes.

summarizes the Nordic diet, emphasizing whole grains, root vegetables, berries, fatty fish, legumes, and rapeseed oil while limiting red meat and processed foods. It highlights mechanisms such as anti-inflammatory and antioxidant effects, improved lipid and glucose metabolism, and cardiovascular protection. The table also outlines health benefits, population suitability, safety considerations, cultural adaptability, environmental sustainability, and the growing evidence supporting its effectiveness for metabolic and cardiometabolic health (Table 7).

Beyond individual health, the Nordic diet underscores sustainability, encouraging the consumption of regionally available foods and environmentally conscious agricultural practices. Research has shown that adherence to this diet is associated with lower risks of cardiovascular diseases, obesity, and type 2 diabetes, as well as improved lipid profiles and blood pressure regulation. Moreover, its emphasis on plant-based foods and marine resources supports not only human health but also planetary well-being. In summary, the Nordic diet represents a scientifically grounded, culturally rooted, and ecologically responsible dietary pattern that integrates nutrition, sustainability, and longevity within a modern health framework (Figure 7).

8.1. Nutritional Composition and Health Benefits

One of the key features of the Nordic diet is its emphasis on whole, minimally processed foods. Research highlights the diet’s benefits for metabolic health, cardiovascular health, and overall well-being [70]. For instance, a study found that adherence to the Nordic diet is linked to improved metabolic markers, such as lower levels of LDL cholesterol and reduced blood pressure, which contribute to a lower risk of CVD [64]. Neurological disorders are significant contributors to global long-term disability and reduced quality of life. Lifestyle factors, particularly dietary patterns, are increasingly recognized as crucial determinants of neurological function. Certain dietary behaviours, such as following the Nordic diet, have been shown to have protective effects on brain function [71].

8.2. Cardiovascular Health

The effect of the Nordic Diet on cardiovascular health is particularly notable. A randomized controlled trial demonstrated that following a Nordic diet can lead to significant improvements in blood lipid profiles and reductions in markers of inflammation [72]. The inclusion of fatty fish, which is rich in omega-3 fatty acids, has been shown to lower triglyceride levels and reduce the risk of heart disease. Adherence to the Nordic Diet was associated with a reduced risk of Myocardial Infarction (MI).

Additionally, the diet’s emphasis on whole grains helps improve overall heart health by reducing cholesterol levels and enhancing vascular function [73]. Results from other studies on Nordic diet variations are consistent from studies with the NORDIET study, resulting in improvements relative to the control diet in blood lipid levels (LDL-C/HDL-C ratio, −0.15; p = 0.046) [74], inflammation (IL-1 receptor, −84 ng/L; p < 0.001) [74], blood pressure levels (DBP, −4.4 mmHg (p = 0.001), and mean arterial pressure levels (−4.2 mmHg; p = 0.006) among metabolic syndrome patients [75] and weight loss (−3.22 kg; p < 0.001) [76] and blood pressure levels reduction (SBP/DBP, −5.13/−3.24 mmHg; p < 0.05) in subjects with obesity [76]. Compared with baseline values, another study demonstrated a decrease in blood pressure of −6.9 mmHg (SBP) and −3.2 mmHg (DBP; p < 0.01) [76,77]. Furthermore, a study done in children resulted in an improvement in status of omega-3 fatty acid with the Nordic diet that was amalgamated with improvements in school performance (p < 0.05) [78]. Another study on the systematic review on the Nordic diet found that evidence supported the protective effects of eating whole grains on type 2 diabetes and CVD risk, but insufficient evidence was found for other foods in the Nordic diet [79].

8.3. Weight Management

The Nordic diet is effective in supporting weight management and reducing the risk of obesity. Research indicates that individuals adhering to the Nordic diet experience significant reductions in body weight and waist circumference, alongside improvements in body composition. The high fibre content promotes feelings of fullness and satiety, helping to prevent overeating and excessive calorie intake, which are crucial for maintaining a healthy weight. Additionally, the inclusion of nutrient-dense, low-calorie foods supports metabolic health and provides essential vitamins and minerals, contributing to overall well-being. The Nordic diet’s balanced approach to nutrition not only aids in weight management but also enhances overall health by reducing the risk of chronic diseases associated with obesity [80]. One randomized, controlled NORDIET study compared a healthy Nordic diet with a control diet (the participants usually followed the Western diet) [81]. Over the period of 6 weeks, the Nordic diet improved the lipid profile and (0.98 mmol/L reduction in total cholesterol levels [p < 0.0001] and a 0.83 mmol/L lower levels in LDL-C [p < 0.001]), decreased SBP by 6.6 mmHg (p = 0.008), and improve in insulin sensitivity (homeostatic model assessment-insulin resistance got lowered to 0.11; p = 0.01) when compared with the control diet. Those following the Nordic diet also experienced a 3.0 kg reduction in body weight (p < 0.001) despite food being available ad libitum [81].

8.4. Unique Features Compared to the Mediterranean Diet

The Nordic diet emphasizes locally sourced, seasonal foods typical of Northern Europe, including whole grains (rye, oats, and barley), fatty fish (salmon, herring, and mackerel), legumes, root vegetables, berries, nuts, and rapeseed oil. Unlike the Mediterranean diet, which relies heavily on olive oil, wine, and a variety of fruits and vegetables from a warmer climate, the Nordic diet focuses on foods suited to colder climates with a higher intake of berries, cabbages, and fatty fish rich in omega-3 fatty acids. Evidence suggests that adherence to the Nordic diet is associated with improved cardiovascular health, lower blood pressure, reduced inflammation, better lipid profiles, and modest weight loss. While both diets share similarities in emphasizing plant-based foods, whole grains, and healthy fats, the Nordic diet has unique bioactive compounds such as anthocyanins from berries and phytosterols from rapeseed oil, which contribute to metabolic benefits. Emerging studies indicate that it can be as effective as the Mediterranean diet in reducing cardiometabolic risk, but regional acceptability and seasonal food availability are important factors for long-term adherence [82].

8.5. Sustainability and Environmental Impact

A unique aspect of the Nordic diet is its focus on sustainability and environmental considerations. The diet emphasizes local and seasonal foods, which helps reduce the carbon footprint associated with food production and transportation. The Nordic diet can significantly lower greenhouse gas emissions and reduce environmental impact compared to diets reliant on imported or heavily processed foods [83]. This aligns with growing concerns about environmental sustainability and encourages a more eco-friendly approach to eating. The Nordic diet offers numerous health benefits, including improved cardiovascular health, effective weight management, and enhanced metabolic markers. Its emphasis on locally sourced, nutrient-dense foods not only supports individual health but also contributes to environmental sustainability [83].

8.6. Safety and Practical Considerations

The Nordic diet, inspired by traditional eating habits of Scandinavian countries, emphasizes locally sourced and seasonal foods such as whole grains (rye, barley, oats), root vegetables, berries, legumes, fish, and rapeseed oil. It is generally considered safe and nutritionally balanced, providing essential macronutrients, fiber, antioxidants, and omega-3 fatty acids that support cardiovascular and metabolic health. However, some practical considerations may influence its long-term adherence and applicability across different populations [84].

One limitation lies in the availability and cost of specific regional ingredients outside Nordic countries, which may reduce feasibility in other settings. Moreover, the diet’s emphasis on fish and high-fiber foods may not suit individuals with specific allergies, gastrointestinal sensitivities, or renal impairments. Excessive consumption of certain oily fish could also raise concerns about mercury exposure, necessitating moderation and informed dietary choices [84]. From a sustainability perspective, the Nordic diet aligns with environmental goals, yet adapting it to non-Nordic regions may require culturally appropriate substitutions to maintain nutritional equivalence. Overall, while the Nordic diet offers substantial benefits for cardiometabolic health and longevity, its safe and effective adoption depends on individualized adjustments, local food availability, and nutritional counselling to ensure both adherence and balance in diverse populations.

9. Comparative Overview of Dietary Patterns

The comparative analysis of major dietary patterns, including the Mediterranean, DASH, plant-based, Blue Zones, intermittent fasting, caloric restriction, and Nordic diets, reveals several unifying principles that contribute to improved health and longevity. The Mediterranean and DASH diets consistently demonstrate robust evidence for reducing cardiovascular and all-cause mortality through high intake of fruits, vegetables, whole grains, nuts, and healthy fats, coupled with limited consumption of red meat and refined sugars. The plant-based and Blue Zones diets, both predominantly vegetarian in nature, emphasize nutrient-dense, minimally processed foods, which lower the risk of chronic diseases such as diabetes, cancer, and obesity while promoting extended lifespan. Emerging dietary approaches such as intermittent fasting and caloric restriction focus on metabolic regulation rather than specific food types [36].

These strategies improve insulin sensitivity, trigger cellular repair mechanisms like autophagy, and activate longevity-associated pathways (SIRT1, AMPK, and mTOR), thereby delaying aging processes and reducing age-related morbidity. Meanwhile, the Nordic diet, inspired by traditional Scandinavian eating habits, integrates sustainability with health, emphasizing locally sourced foods such as berries, fish, root vegetables, and whole grains. Studies associate this diet with lower cardiovascular mortality and enhanced metabolic health. Collectively, these dietary patterns share key attributes: high intake of plant-based and unprocessed foods, moderate protein consumption, and balanced fat intake that contribute to improved metabolic function, reduced inflammation, and prolonged health span.

Table 8. Comparative Overview of Major Dietary Patterns and Their Impact on Longevity and Mortality Outcomes.

Dietary Pattern	Key Features/Principles	Core Food Components	Health & Longevity Outcomes	Mechanistic Insights
Mediterranean Diet	Emphasizes balanced intake of healthy fats, fruits, vegetables, and whole grains; minimal red meat and sweets.	Olive oil, fruits, vegetables, legumes, nuts, seeds, fish, whole grains, moderate dairy, limited red meat.	Reduced cardiovascular and all-cause mortality; lower incidence of diabetes, obesity, and cancer; improved longevity.	Rich in monounsaturated fats, antioxidants, and polyphenols; improves lipid profile and reduces inflammation.
DASH Diet (Dietary Approaches to Stop Hypertension)	Designed to lower blood pressure; emphasizes fruits, vegetables, and low-fat dairy with reduced sodium.	Fruits, vegetables, whole grains, lean protein, nuts, seeds, low-fat dairy; minimal saturated fat and added sugars.	Decreases cardiovascular mortality; lowers blood pressure and risk of stroke; improves overall survival.	Enhances vascular function, reduces sodium-induced hypertension, and promotes metabolic balance.
Plant-Based Diet	Focuses on plant-derived foods; excludes or limits animal products.	Fruits, vegetables, legumes, nuts, seeds, whole grains; limited or no meat, dairy, or eggs.	Lower risk of cardiovascular disease, type 2 diabetes, and certain cancers; improved lifespan.	High in fiber and phytonutrients; reduces oxidative stress and systemic inflammation.
Blue Zones Diet	Based on dietary habits of the world’s longest-living populations (Okinawa, Ikaria, Nicoya, Loma Linda, Sardinia).	Primarily plant-based foods, legumes, whole grains, nuts, minimal meat and processed foods, moderate wine (regionally).	Strong association with exceptional longevity and low rates of chronic diseases.	Promotes nutrient density, caloric moderation, and social-meal patterns supporting psychological well-being.
Intermittent Fasting (IF)	Alternates between eating and fasting periods (e.g., 16:8, 5:2 patterns).	Flexible—focus on timing rather than specific foods; often combined with balanced, nutrient-rich meals.	Enhances metabolic flexibility; reduces risk of age-related diseases; potential lifespan extension.	Triggers autophagy, improves insulin sensitivity, and modulates circadian rhythm and mitochondrial efficiency.
Caloric Restriction (CR)	Sustained reduction in caloric intake without malnutrition.	Reduced overall calories while maintaining essential nutrients.	Demonstrated lifespan extension in experimental models; may reduce age-related morbidity in humans.	Activates longevity pathways (SIRT1, AMPK, mTOR); reduces oxidative damage and metabolic stress.
Nordic Diet	Reflects traditional Nordic eating habits emphasizing sustainability and local produce.	Whole grains (oats, rye, barley), fish, berries, root vegetables, legumes, low-fat dairy, lean meats.	Associated with reduced cardiovascular mortality, obesity, and diabetes; supports longer healthspan.	Rich in omega-3s, fiber, and polyphenols; improves lipid metabolism and gut microbiome composition.

provides a comparative overview of major dietary patterns, summarizing their key principles, core foods, health and longevity outcomes, and underlying mechanisms. It highlights how diets such as Mediterranean, DASH, plant-based, Blue Zones, intermittent fasting, caloric restriction, and Nordic diets contribute to reduced mortality, improved cardiometabolic health, and potential lifespan extension through mechanisms like anti-inflammatory effects, improved lipid and glucose metabolism, autophagy, and modulation of gut microbiota. This table facilitates an integrated understanding of diet–longevity relationships across different dietary approaches (Table 8). Therefore, adopting the core principles of these diets can offer synergistic benefits for cardiovascular health, chronic disease prevention, and overall longevity [36].

10. Molecular and Physiological Mechanisms Linking Dietary Patterns to Longevity

The influence of dietary patterns on longevity operates through a complex interplay of molecular, cellular, and physiological mechanisms that transcend mere nutrient composition. Contemporary research highlights that certain diets, particularly those rich in phytonutrients, unsaturated fatty acids, and antioxidants, exert profound regulatory effects on metabolic signaling networks involved in aging and disease resistance [55]. Central to these mechanisms is the activation of autophagy, a conserved cellular process that facilitates the clearance of damaged organelles and proteins, thereby maintaining proteostasis and delaying senescence [85]. Concurrently, these diets modulate inflammatory pathways by downregulating pro-inflammatory cytokines and mediators through NF-κB inhibition and by enhancing Nrf2-dependent antioxidant responses, collectively mitigating chronic low-grade inflammation, a recognized hallmark of aging [86,87]. In parallel, dietary modulation of mitochondrial function plays a pivotal role in sustaining energy metabolism and redox balance, preventing the accumulation of reactive oxygen species that contribute to cellular deterioration [88]. Emerging evidence also underscores the gut–brain–immune axis as a critical conduit through which diet influences systemic longevity. Nutritional modulation of gut microbiota composition fosters the enrichment of beneficial taxa that produce metabolites such as short-chain fatty acids (butyrate, propionate) and secondary bile acids, which in turn regulate lipid metabolism, epigenetic signaling, and immune homeostasis [89,90].

Taken together, these mechanistic insights illustrate that dietary influences on longevity are mediated by integrative bio-regulatory networks encompassing autophagy induction, inflammatory control, mitochondrial resilience, and microbiome-derived molecular crosstalk [91,92,93]. Understanding the synergy between these pathways provides a unifying biological framework that explains how optimal dietary patterns can modulate healthspan and delay the onset of age-associated chronic diseases.

11. Conclusions

In conclusion, the exploration of longevity-boosting diets reveals a compelling connection between dietary patterns and extended lifespan. From the Mediterranean and DASH diets to plant-based regimens and intermittent fasting, each approach offers unique benefits that contribute to health and longevity. The Mediterranean diet, with its emphasis on healthy fats, lean proteins, and abundant fruits and vegetables, has demonstrated significant impacts on cardiovascular health and metabolic function. Similarly, the DASH diet’s focus on reducing sodium and increasing intake of nutrient-rich foods supports better blood pressure management and overall cardiovascular health. Plant-based diets stand out for their potential to lower the risk of chronic diseases and promote long-term wellness through high fiber content and reduced intake of saturated fats. Intermittent fasting, through its structured eating patterns, not only aids in weight management but also enhances metabolic health and cellular repair processes.

Meanwhile, caloric restriction continues to be a valuable strategy for reducing age-related diseases and extending lifespan by modulating key biological pathways. The Nordic diet, with its focus on local, seasonal foods, complements these dietary approaches by aligning nutritional benefits with environmental sustainability. Collectively, these diets underscore the importance of a balanced, varied approach to eating that prioritizes whole, minimally processed foods while integrating lifestyle factors that support overall health. This review, therefore, provides a unique synthesis of multiple evidence-based dietary patterns within a unified framework of longevity and health optimization. By comparing their nutritional compositions, physiological mechanisms, and population-based outcomes, it offers new insights into the shared biological pathways such as reduced inflammation, improved metabolic regulation, and enhanced cardiovascular resilience that underpin healthy aging. The novel contribution of this work lies in emphasizing the synergistic principles common to these diets, offering an integrative perspective for developing personalized and sustainable dietary strategies for an extended health span. As research advances, the integration of these dietary principles into daily life offers a promising pathway to achieving longevity and improved quality of life.

12. Future Research Directions

Future research should focus on elucidating the molecular and circadian mechanisms through which these dietary patterns influence longevity and disease resistance. Large-scale longitudinal and intervention studies are needed to compare these diets in diverse populations and to identify biomarkers of dietary adherence and metabolic adaptation. Integrating nutrigenomics, microbiome analysis, and chrono-nutrition approaches could further clarify how genetic and temporal factors modulate the benefits of each diet. From a practical standpoint, these insights can guide the development of personalized nutrition models that combine the most beneficial components of different diets according to individual metabolic profiles, cultural preferences, and environmental sustainability. Public health programs should also prioritize nutrition education and community-based interventions promoting whole foods, mindful eating, and reduced consumption of processed products. Such translational applications will strengthen preventive strategies, optimize health span, and support global longevity initiatives.