Search Results (132)

Background: Evidence comparing the effects of novel alternative dietary strategies on resting energy expenditure (REE) with a hypocaloric standard Mediterranean diet (MedDiet) with continuous caloric restriction remains limited. This study aimed to evaluate the effects of diets with varying ketogenic potentials—including a very-low-carbohydrate diet (ketogenic diet, KD), time-restricted eating (TRE), and modified alternate-day fasting (mADF)—on the REE of individuals with obesity compared to those of a standard MedDiet. Methods: This was a secondary post hoc sub-analysis of a three-month, parallel-arm, randomized clinical trial (RCT) including 160 adults with obesity (body mass index > 30 kg/m²). The participants were randomly assigned to one of five calorie-restricted dietary interventions: control (MedDiet), KD, early time-restricted eating (eTRE), late time-restricted eating (lTRE), or mADF. All interventions featured an individualized energy deficit of 600 kcal/day. In this sub-analysis, a total of 102 participants with valid baseline measures were included. The REE was assessed by indirect calorimetry, and longitudinal trajectories were evaluated using Linear Mixed Models (LMMs) in 98 participants to account for baseline variability and to maximize data retention. Results: The mean age of participants in this sub-analysis was 45.3 years (SD 10.8), and 73.1% were women. The longitudinal modeling confirmed no statistically significant differences in the adjusted REE trajectories among the five dietary groups over the 3-month intervention (Group × Time interaction, p = 0.506). Furthermore, the LMMs showed that total body weight (p < 0.001) and biological sex (p < 0.001) were the variables most strongly associated with REE within the model. No independent associations between circulating beta-hydroxybutyrate levels and REE trajectories were detected. Conclusions: Hypocaloric diets with varying macronutrient distributions and fasting windows did not show statistically significant differences in REE trajectories over the 3-month intervention. In this exploratory sub-analysis, the REE trajectories were more closely associated with individual biological characteristics, particularly body weight and sex, than with the specific dietary strategy employed. Given the modest sample size and exploratory nature of the study, these findings should be interpreted cautiously and require confirmation in larger, adequately powered prospective trials. Full article

Background: Obesity is a chronic endocrine–metabolic disorder. The risk of comorbidities increases with a higher body mass index (BMI), particularly when BMI ≥ 35.0 kg/m². Common complications include insulin resistance, type 2 diabetes, dyslipidemia, and chronic low-grade inflammation, which collectively impair DNA stability by promoting the formation of genotoxic species. Methods: This non-randomised, quasi-experimental clinical intervention study included 53 participants (both sexes) with a BMI ≥ 35.0 kg/m², who were assigned to parallel experimental or control streams based on clinical needs and institutional eligibility. During a three-week intervention, the experimental group received a hospital-supervised very-low-calorie diet (VLCD; ~600 kcal/day) under continuous medical monitoring. Conversely, the control group followed a standard reduced-calorie diet (SRD) of 1500 kcal/day in a free-living home environment. Before and after the intervention, primary, oxidative, and permanent DNA damage were measured using alkaline, FPG-modified comet (peripheral blood mononuclear cells), and cytokinesis-block micronucleus cytome assays (phytohaemagglutinin-stimulated binucleated lymphocytes), alongside anthropometric and biochemical tracking. Results: Within-group evaluations revealed that both dietary regimens improved several metabolic health indicators, notably modulating insulin resistance, lipid profiles, and leukocyte counts. However, participants in the VLCD stream experienced significantly greater downward changes in body weight, BMI, and absolute lipid values. Crucially, the VLCD intervention was associated with a highly significant within-group reduction in parameters of permanent chromosomal damage, effectively halving the frequencies of micronuclei and nuclear buds, independent of baseline variations, in adjusted multivariate regression models. Conversely, the home-based SRD regimen demonstrated no measurable impact on permanent genomic damage. Neither diet induced a significant change in repairable primary or oxidative DNA lesions over this short timeframe. Conclusions: These exploratory findings suggest that strict calorie restriction can rapidly stabilise genome stability in advanced clinical settings, warranting future randomised controlled trials with long-term longitudinal follow-up to assess permanent risk reductions. Due to structural baseline variations in age, chronic comorbidities, and compliance environments between the cohorts, direct comparative superiority cannot be definitively established. Full article

Background: Serum uric acid (UA) is increasingly recognized as a cardiovascular (CV) risk factor, with evidence suggesting that CV risk may occur at levels below conventional hyperuricemia thresholds. However, real-world comparative data on the effects of dietary interventions on UA are limited. Objective: The primary objective of this study was to compare the effects of a very low-calorie ketogenic diet (VLCKD), intermittent fasting (IF), and standard dietary advice (free diet, FD) on UA levels and UA-defined CV risk in hypertensive postmenopausal women. Methods: In this prospective, single-center, real-world clinical study, 43 women with essential hypertension and obesity underwent dietary interventions. UA levels were assessed at baseline and after 6 months. Hyperuricemia was defined using both the conventional threshold (≥6.0 mg/dL) and the CV risk-oriented Uric Acid Right for Heart Health (URRAH) cut-off (≥4.7 mg/dL). Analyses included paired tests and ANCOVA adjusted for baseline UA. Results: At baseline, over half of participants exceeded the URRAH threshold. Only VLCKD significantly reduced UA levels (−1.23 mg/dL; p < 0.001), remaining independently associated after adjustment (β = −0.95 mg/dL; p = 0.007). URRAH-defined CV risk decreased significantly only in the VLCKD group (55.6% to 22.2%), with one-third transitioning to lower risk. Conclusions: VLCKD significantly reduced UA levels and UA-defined CV risk, supporting its role as a potentially effective lifestyle intervention in this population. Full article

Background: The very-low-calorie ketogenic diet (VLCKD) is increasingly used before bariatric surgery (BS), but its effects on surgical and long-term outcomes remain unclear. Objective: The aim of this study was to compare the impact of a 4-week VLCKD with a 4-week low-calorie diet (LCD) on preoperative, perioperative and postoperative outcomes for up 12 months in patients undergoing BS. Methods: In this prospective study, 72 (n = 36: VLCKD; n = 36: LCD) patients (mean age 43.2 ± 10.6 years; BMI 45.6 ± 6.4 kg/m²; 87.5% female) submitted to sleeve gastrectomy were enrolled at a tertiary care center from 2022 to 2024. Results: No adverse events were detected with both diets. The VLCKD was associated with a greater preoperative median weight loss percentage (−5.5 vs. −2.6 kg, p < 0.001), BMI reduction (−2.6 vs. −1.2 kg/m², p < 0.001), shorter hospital stay (3.0 ± 0.2 vs. 3.4 ± 0.9 days, p = 0.017), higher day-1 postoperative hemoglobin (12.7 ± 1.3 vs. 12.0 ± 1.2 g/dL, p = 0.024), and lower day-1 postoperative median C-reactive protein levels (9.7 vs. 13.4 mg/L, p = 0.042). These associations were confirmed in a multiple regression model, after adjustments for BMI at enrolment, age and sex. After 6 months, the VLCKD was associated with greater reductions in mean weight loss percentage (−24.9 ± 7.8 vs. −19.6 ± 9.4 kg, p = 0.012), BMI reduction (−11.7 ± 4.4 vs. −8.7 ± 3.9 kg/m², p = 0.003), neck circumference (−4.9 vs. −3.6 cm, p = 0.027) and lower aminotransferase levels. At 12 months, VLCKD patients maintained significant advantages over the same variables, except for neck circumference. Conclusions: A short preoperative VLCKD was safe and was associated with greater short-term weight reduction compared with the LCD, with potential benefits extending to early postoperative recovery and 1-year outcomes. Full article

Background/Objectives: Obesity is a chronic, relapsing disease in which lifestyle modification represents the cornerstone of treatment. Among dietary strategies, ketogenic diets can induce rapid weight loss, whereas the Mediterranean diet is associated with established cardiometabolic benefits but typically produces slower weight reduction. Very-low-calorie ketogenic diets (VLCKDs) are effective for weight loss but are often limited by cost, reliance on meal replacements, and reduced long-term feasibility. This study aimed to evaluate whether a whole-food Mediterranean ketogenic diet with moderate caloric restriction (MedKD) could represent a feasible and effective alternative to VLCKD for weight loss and metabolic improvement in adults with obesity. Methods: This 3-month prospective, real-world study compared VLCKD and MedKD in adults with obesity attending a clinical nutrition program. The primary outcome was percentage weight loss. Secondary outcomes included changes in waist circumference, waist-to-height ratio, insulin resistance (HOMA-IR), lipid profile, kidney function, and treatment tolerability. Clinical and biochemical parameters were assessed at baseline and after the intervention. Group differences and time-by-group interactions were analyzed to evaluate changes over the study period. Results: Sixty-two participants were enrolled, and 55 completed the study (27 VLCKD, 28 MedKD). Baseline characteristics were generally comparable, although the MedKD group had a higher prevalence of diabetes and higher baseline insulin resistance and triglyceride levels. Both dietary interventions resulted in substantial and comparable weight loss (approximately 15% of initial body weight), accompanied by significant reductions in waist circumference and waist-to-height ratio. Insulin resistance improved in both groups, with a greater reduction in HOMA-IR observed in the MedKD group (time × group p = 0.031). Serum creatinine decreased in the VLCKD group and slightly increased in the MedKD group (p = 0.025). Changes in lipid profile were not significantly different between groups. No severe adverse events were reported. Conclusions: A whole-food Mediterranean ketogenic diet with moderate caloric restriction achieved weight loss and metabolic improvements comparable to those observed with VLCKD over three months. These findings suggest that MedKD may represent a feasible alternative to formula-based ketogenic programs, supporting more flexible and personalized dietary strategies in the clinical management of obesity. Full article

Precision nutrition has emerged as a promising strategy for the prevention of type 2 diabetes mellitus (T2DM) by targeting molecular pathways underlying insulin resistance and impaired glucose metabolism. Accumulating evidence indicates that dietary patterns, caloric intake, and specific nutrients can modulate gene expression and epigenetic mechanisms involved in insulin signaling, inflammation, and energy homeostasis. This narrative review synthesizes recent human and experimental studies (2025–2026) examining how dietary components influence transcriptional and epigenetic regulation of insulin signaling and glucose metabolism in the context of T2DM prevention. A total of 29 peer-reviewed studies were included, encompassing dietary patterns, macronutrient manipulation, micronutrient and bioactive supplementation, and gene–diet interactions. Very-low-calorie diets consistently induced coordinated modulation of key metabolic genes, including downregulation of glucose transporter type 4 (GLUT4) and upregulation of PDK4, CPT1, and AMPK, reflecting a metabolic shift toward enhanced fatty acid oxidation and improved insulin sensitivity. In contrast, high-fat and fructose-rich diets promoted proinflammatory gene expression and immune activation, contributing to insulin resistance. Plant-based and vegan dietary patterns were associated with reduced epigenetic aging and improved insulin sensitivity through DNA methylation changes. Targeted interventions, including vitamin D combined with probiotics, dietary fiber, nucleotides, and trace elements such as copper, further demonstrated favorable transcriptional and epigenetic effects linked to improved glycemic control. Collectively, these findings highlight diet-driven modulation of insulin signaling and glucose metabolism at the molecular level and support nutrigenomics-guided precision nutrition as a viable preventive approach for T2DM. Integrating genetic and epigenetic insights into dietary strategies may enable more personalized and effective interventions to curb the growing global burden of type 2 diabetes. Full article

Background/Objectives: Obesity is a chronic relapsing disorder associated with many comorbidities. Some evidence suggests that oxytocin (OT) has an anorexigenic effect, but its levels are often increased in obesity. This study investigates the effects of weight loss induced by a very-low-calorie ketogenic diet (VLCKD) on oxytocin levels. Methods: A total of 47 subjects with overweight or obesity, 28 females (60%) and 19 males, with a mean age of 55.5 ± 7.3 years and mean BMI 35.9 ± 4.4 kg/m², underwent VLCKD for 45 days. We assessed anthropometric parameters, metabolic profile, body composition and OT levels at baseline (t0) and at the end of the diet (t1). Results: After weight loss, plasma OT levels significantly dropped. Baseline OT correlated with BMI, fat mass and trunk fat. A linear relationship was observed between Delta OT levels and Delta BMI. Baseline OT was an independent predictor of weight loss and directly correlated with blood ketone levels at the end of the study. An optimal serum OT cut-off that predicts ketosis occurrence was identified. Conclusions: Weight loss obtained with a VLCKD reduces OT levels in patients with excess weight. Baseline OT predicts weight loss and correlates with ketone body levels during a VLCKD. Full article

Background: Metabolic syndrome (MetS) is a multifactorial condition characterized by insulin resistance, dyslipidemia, hypertension, and central obesity, and is strongly influenced by lifestyle factors. Growing evidence highlights the gut microbiota as a key mediator linking diet and physical exercise to cardiometabolic health. Objective: This narrative review aims to qualitatively synthesize current evidence on the effects of physical exercise and major dietary patterns including the Mediterranean diet (MedDiet), Dietary Approaches to Stop Hypertension (DASH), and ketogenic/very-low-calorie ketogenic diets (KD/VLCKD) on gut microbiota composition and function, and their implications for metabolic health in MetS. Methods: A qualitative narrative synthesis of experimental, observational, and interventional human and animal studies was performed. The reviewed literature examined associations between structured physical exercise or dietary interventions and changes in gut microbiota diversity, key bacterial taxa, microbial metabolites, and cardiometabolic outcomes. Considerable heterogeneity across studies was noted, including differences in populations, intervention duration and intensity, dietary composition, and microbiota assessment methodologies. Results: Across human interventional studies, moderate-intensity physical exercise was most consistently associated with increased gut microbial diversity and enrichment of short-chain fatty acid (SCFA)-producing taxa, contributing to improved insulin sensitivity and reduced inflammation. MedDiet and DASH were generally linked to favorable microbiota profiles, including increased abundance of Faecalibacterium prausnitzii, Akkermansia muciniphila, and Bifidobacterium, alongside reductions in pro-inflammatory metabolites such as lipopolysaccharides and trimethylamine N-oxide. In contrast, KD and VLCKD were associated with rapid weight loss and glycemic improvements but frequently accompanied by reductions in SCFA-producing bacteria, depletion of Bifidobacterium, and markers of impaired gut barrier integrity, raising concerns regarding long-term microbiota resilience. Conclusions: Lifestyle-based interventions exert diet- and exercise-specific effects on the gut microbiota–metabolism axis. While MedDiet, DASH, and regular moderate physical activity appear to promote sustainable microbiota-mediated cardiometabolic benefits, ketogenic approaches require careful personalization, limited duration, and medical supervision. These findings support the integration of dietary quality, exercise prescription, and individual microbiota responsiveness into translational lifestyle strategies for MetS prevention and management. Full article

Background: The comparative effects of pharmacological treatment, bariatric surgery, and diet on insulin resistance (IR) remain unclear. Aim: To study the comparative effects of the methods on IR: pharmacologic, bariatric surgery, and very-low-calorie diet (VLCD) in patients with type 2 diabetes mellitus (T2DM) and hypertension. Methods: Design: a 90-day prospective, multicenter, comparative clinical trial including 130 adult patients divided into three groups: Drug, Surgery, and VLCD. Endpoints: HOMA-IR; weight loss; and HbA1c, systolic/diastolic blood pressure (SBP/DBP). Results: At 90 days, weight loss in the Surgery (−19.8%) and VLCD groups (−17.4%) was significant (p < 0.0001), while in the Drug group, the loss was insignificant (−6.5%; p = 0.06). SBP/DBP in the Drug group decreased by −9.5% (p = 0.0002) and −4.1% (p = 0.09), respectively. SBP/DBP in the Surgery group decreased by −13.6% and −10.6%, respectively (p < 0.001), and in the VLCD group, by −23.3% and 21.3%, respectively (p < 0.0001). HOMA-IR in Drug, Surgery, and VLCD groups decreased by −42.2% (p = 0.004), −87.6% (p < 0.0001), and −88.7% (p < 0.0001), respectively. In the Drug group, HOMA-IR did not reach the normal level. Correlation-regression analysis revealed a direct correlation between weight loss and a decrease in HOMA-IR (r = 0.526; F = 33.2, p < 0.0001). HOMA-IR decreases by 65% if weight decreases by 10%; if weight decreases by 25%, then HOMA-IR decreases by 83%. Conclusions: HOMA-IR was associated with weight loss: the greater the weight loss, the lower the HOMA-IR. Weight loss leads to a reduction in the need for antidiabetic/antihypertensive drugs in patients with T2DM and hypertension. Full article

Background: Obesity is a multifactorial chronic disease associated with increased risk of metabolic disorders, reduced quality of life, and rising healthcare costs. Although weight reduction is achievable through various dietary approaches, maintaining the achieved results remains a major clinical challenge. This review aims to identify and discuss dietary, behavioral, and lifestyle strategies that support long-term weight loss and weight maintenance. Methods: A narrative literature review was conducted in two stages using PubMed, Scopus, and Google Scholar. The search included peer-reviewed studies published between 2015 and 2025 focusing on individuals with overweight and obesity. Randomized controlled trials, observational studies, systematic and narrative reviews, and meta-analyses discussing short-term and long-term weight loss outcomes and factors influencing the maintenance of reduced body weight were included. Results: Multiple nutritional strategies, including continuous and intermittent energy restriction, very low-calorie diets, and macronutrient modification, can be effective for weight reduction. However, long-term outcomes are primarily dependent on adherence and consistent implementation of recommendations. Behavioral and psychological factors, such as emotional eating, dietary fatigue, and unrealistic expectations, often contribute to weight regain. Social support, personalized dietary strategies, and sustainable lifestyle habits are key determinants of maintaining weight loss. The current evidence base is limited by the scarcity of long-term follow-up studies and high methodological variability across interventions. Conclusions: Long-term weight management requires a comprehensive, individualized approach that integrates dietary strategies with behavioral and lifestyle support. Strengthening adherence and addressing psychological and environmental factors may significantly improve the effectiveness and durability of obesity treatment. Full article

Background: Migraine is a common, disabling neurological disorder with substantial genetic and environmental contributions. Dietary exposures are widely discussed by patients and clinicians as potential triggers or modifiers of attack frequency and severity. We synthesized contemporary evidence on dietary patterns, specific nutrients, and elimination strategies relevant to migraine prevention and management. Methods: We performed a narrative review of PubMed and Google Scholar (inception–August 2025) using combinations of “migraine”, “diet”, “nutrition”, “ketogenic”, “Mediterranean”, “omega-3”, and “gluten”. We prioritized randomized/controlled studies, recent systematic reviews/meta-analyses, and representative observational studies; evidence quality and applicability were appraised descriptively. Results: Higher adherence to a Mediterranean-style diet is associated with lower migraine frequency and disability in observational cohorts. Very low-calorie ketogenic diets significantly reduced monthly migraine attack frequency compared with isocaloric non-ketogenic comparators in an adult randomized controlled trial of participants with overweight or obesity (≥50% responder rate: 74% vs. 6%). Additional supportive evidence from uncontrolled studies, including those involving medium-chain triglyceride supplementation, further corroborates these findings. Omega-3 fatty acids (EPA/DHA) show prophylactic benefit in randomized trials and network meta-analyses, with favorable tolerability. Gluten-free diets may improve headaches in celiac disease and may help selected non-celiac patients. Alcohol (especially red wine) and high, irregular caffeine intake are frequently reported triggers, while evidence for specific foods/additives remains inconsistent. Weight loss and regular physical activity may further reduce burden in people with obesity. Conclusions: Current evidence supports recommending Mediterranean-style eating, consideration of omega-3 supplementation, and selective trials of ketogenic or elimination approaches in appropriate patients, alongside weight management and lifestyle optimization. High-quality, longer-duration RCTs using standardized dietary protocols and adherence biomarkers are needed to define dose–response relationships and enable personalized nutrition in migraine. Full article

Biathlon is a winter Olympic sport that combines high-intensity cross-country skiing with precise rifle shooting. These dual demands require athletes to develop exceptional aerobic capacity while maintaining fine motor accuracy under physiological stress. Despite its complexity, nutritional strategies in biathlon remain under-explored and recommendations are often extrapolated from related endurance sports. This narrative review aims to summarise existing knowledge on nutrition in biathlon, highlight sport-specific challenges and identify areas for future research. The main findings indicate that biathletes face very high energy demands, with daily expenditure exceeding 7000 kcal during intensive training. Carbohydrates are the primary fuel source, with intake recommendations based on training intensity and duration (6–12 g/kg/d). Furthermore, protein is essential for muscle repair, recovery and adaptation. To achieve the recommended intake of 1.6 g/kg/day, it is advisable to consume meals containing approximately 0.3 g/kg of high-quality protein every three to four hours. Given the frequency of training sessions, effective recovery strategies are important in biathlon. When recovery is a priority, biathletes should consume a meal comprising protein (approximately 0.3 g/kg) and carbohydrates (approximately 1.2 g/kg) before key training sessions. Micronutrient and vitamin deficiencies are not commonly observed in biathletes due to their high calorie intake. However, concerns regarding iron and vitamin D are common among endurance athletes due to the high risk of low energy intake, diets lacking in iron, and insufficient exposure to sunlight. On the day of the race, it is recommended that biathletes plan their meals to ensure that they meet their nutritional needs and begin recovery as soon as possible after the race is over. Biathletes may use specific supplements to enhance performance and health during preparation and competition. However, it is important to note that some supplements that improve performance may harm shooting accuracy. Current guidance is provisional, and future research should adopt a dual-performance framework that evaluates both endurance output and shooting precision under realistic competition conditions. Full article

Genetic background, the “Western diet”, and environment may all contribute to hyperinsulinemia. Hyperinsulinemia can precede and cause insulin resistance. In situations of fuel overload, insulin resistance limits the amount fuel (glucose and fatty acids) entering insulin-sensitive tissues. When energy intake is chronically greater than energy expenditure, the capacity of the subcutaneous fat tissues to store fat can be overpowered. If subcutaneous fat tissues are no longer able to accommodate excess energy, there will be spillover of lipids. Excess calories will be stored as ectopic fat (triglycerides) in the liver, pancreas, and skeletal muscle. Growing evidence suggests that ectopic fat deposition directly causes insulin resistance and pancreatic beta cell dysfunction. Overnutrition and ectopic fat increase diacylglycerol (DAG) accumulation in fat cells, hepatocytes, and skeletal muscle cells. A unifying hypothesis proposes that translocated DAG into the plasma membrane induces insulin resistance in all these three cell types. In addition, ectopic fat accumulation in the pancreas induces beta-cell dysfunction. Introducing a negative energy balance by bariatric surgery or a very low-calorie diet (VLCD) reduces ectopic fat depositions from the liver and pancreas and decreases intracellular DAG content: both are effective treatments to restore insulin sensitivity, normalize metabolism, and put type 2 diabetes in remission. Full article

Background: Elevated BMI in women is linked to metabolic and endocrine imbalances that impair fertility and increase pregnancy risks. While >10% weight loss before an Assisted reproductive technology (ART) treatment may improve outcomes, sustained results through conventional diets are challenging. A very-low calorie ketogenic diet (VLCKD) promotes rapid fat loss while preserving lean mass and may offer long-term benefits. This study evaluated the efficacy (≥10% weight loss without lean mass reduction), adherence, metabolic effects, and pregnancy outcomes of a meal replacement VLCKD in women with overweight or obesity scheduled for ART. Methods: This monocentric, prospective case-series was conducted at the Obesity and Work Center, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan (September 2019–September 2023). Eligible women underwent a three-phase dietary program: a 3-month VLCKD (<800 kcal/day), a 6-month transition with gradual carbohydrate reintroduction, and a Mediterranean-style maintenance diet. Participants were monitored for safety, body composition, adherence, and biochemical changes. Results: Of 52 women enrolled, 40 initiated the VLCKD; 27 (68%) achieved ≥10% weight loss while preserving lean mass. Eleven conceived naturally during or after the diet; 22 underwent ART, with 12 additional pregnancies. This corresponds to a 58% pregnancy rate among those who began the VLCKD. Significant improvements were observed in body mass index (BMI), fat mass, waist circumference, glucose metabolism, lipid profile, and liver function. No adverse events were reported. Conclusions: A meal replacement VLCKD protocol is feasible, well-tolerated, and associated with significant improvements in weight, especially in body composition, metabolic health, and potentially outcomes in women with overweight or obesity awaiting ART. Full article

Background/Objectives: Polycystic ovary syndrome (PCOS) is the most common endocrinopathy experienced by females. Diagnosis of PCOS is established when at least two of the following are present: hyperandrogenism, oligo-anovulation, and/or polycystic ovaries. Conservative treatment for PCOS includes dietary modifications and physical activity. The purpose of this scoping review was to evaluate the efficacy of a ketogenic diet in improving biochemical measures and reducing the severity of PCOS symptoms. Methods: CINAHL, PubMed, and Google Scholar databases were searched to find research published in peer-reviewed journals between 2019 and 2025. An article was included in this scoping review if the study assessed the effectiveness of a ketogenic diet on improving the signs and symptoms in patients with PCOS. Results: Eight studies met the inclusion criteria. Weight loss was achieved by subjects who adopted a very low-calorie ketogenic diet (VLCKD), low-calorie ketogenic diet (LCKD), classic ketogenic diet (CKD), or a Mediterranean eucaloric ketogenic diet (KEMEPHY). Patients with PCOS who consumed a ketogenic diet experienced improved biochemical measures, including androgen levels, lipid levels, HOMA-IR, blood glucose, insulin, LH/FSH ratio, DHEAS, SHBG, AFC, and AMH. A ketogenic diet was also associated with improvements in menstruation, fertility, and OHSS. Conclusions: Adopting a short-term ketogenic diet may have positive health benefits for patients with PCOS. Full article