Search Results (76)

Background/Objectives: Stevia rebaudiosides represent a class of compounds extracted from the Stevia rebaudiana Bertoni plant or produced via yeast fermentation, which provide a sweet taste with little to no calories. These compounds are commercially referred to as stevia and are used in the food industry to reduce sugar in foods and beverages. Stevia is a non-nutritive sweetener (NNS), which is a class of ingredients which represent both artificial and plant-based sweeteners. NNSs are widely used and have been well studied. However, their effects on efficacy for weight management as a sugar reduction tool and overall metabolic effects are inconsistent. Of the approved NNSs for use, stevia is relatively new and one of the least studied. However, recent human clinical research has provided insights into stevia’s metabolic effects, effects on the gut microbiome and effects on weight management when used to replace sugar. The objective of this narrative review of human clinical studies is to provide an overview of the effects of stevia rebaudiosides (largely rebaudioside A) on glucoregulatory and cardiometabolic functions, as well as their effects on gut microbiome and weight management. These studies were typically short term (acute to three months) and heterogeneous by design, and they contained stevia rebaudiosides as lone sweeteners and as part of a binary blend with other NNSs. The majority of metabolic studies on stevia rebaudiosides have evaluated the effects on glucose homeostasis and, to a lesser extent, the effects on cardiometabolic function, the gut microbiome, and weight management. These studies suggest that stevia rebaudiosides have no statistically significant effects on glycemia, insulinemia, blood lipids, appetite hormones, or the gut microbiome. Limited studies suggest that, particularly when compared to sucrose, stevia produces very modest body weight and BMI changes, while studies on subjective appetite and food intake have had inconsistent results. Conclusions: Longer-term studies are needed, with more consistent and rigorous design protocols across various populations. However, current human clinical studies suggest that stevia rebaudiosides have a limited impact on metabolic functions, and the observed effects on gut microbiome and changes in body weight, particularly when used to replace sugar, warrant further study. Full article

Background: For decades, the ketogenic diet has been successfully used for the treatment of obesity, metabolic syndrome, and type 2 diabetes. The mechanisms through which it affects metabolism are not fully understood, but the hormonal changes that occur during ketogenic nutrition are likely to play an important role. Objectives: To investigate the effect of the ketogenic diet on various hormones associated with obesity and the accompanying metabolic disorders in childhood. Methods: One hundred children aged 8–18 years with obesity were enrolled. After baseline anthropometric, biochemical, and hormonal testing, they followed a 4-month “well-formulated ketogenic diet.” Fifty-eight of them successfully completed the study with follow-up assessments. Among them, 8 girls had polycystic ovary syndrome (PCOS) and 7 children had Hashimoto’s autoimmune thyroiditis. Results: At the end of the 4-month period, there was a significant decrease in basal insulinemia (p < 0.0001) and in mean morning cortisol levels (p = 0.04), as well as an increase in adiponectin levels (p = 0.04). All girls with PCOS experienced spontaneous menstrual cycles, accompanied by a reduction in testosterone levels. TSH levels showed no change for the whole group (p = 0.13), but there was a significant decrease in T3 (p < 0.0001) and a mild increase in T4 (p = 0.05). Among patients with Hashimoto’s thyroiditis, TSH levels were significantly higher at the end of the study. Conclusions: A short-term, well-formulated ketogenic diet in children with obesity is associated with hormonal changes that support weight loss and improve insulin sensitivity. The diet shows particularly beneficial effects in girls with PCOS and may be considered as part of a comprehensive therapeutic approach in these patients. Monitoring thyroid function during ketogenic nutrition is advisable in patients with hypothyroidism and thyroid disorders. Full article

Background/Objectives: Modifying standard foods to minimize postprandial glucose (PPG) and insulin excursions may benefit health. We conducted a randomized, double-blind, crossover study to compare postprandial responses to an isocaloric (~250 kcal) Standard Muffin (SM) containing refined flour and sugar versus a Modified Muffin (MM) consisting of wheat-free grains and low sugar levels in healthy individuals and individuals with type 2 diabetes (T2D). Subjects/Methods: Nineteen subjects (ten healthy, nine with T2D) participated in the trial. PPG responses were measured in capillary blood over 5 h to calculate the change in glucose from the baseline (ΔGLU), peak glucose (GLU_Peak), peak–nadir glucose (GLU_P-N), and 2 h incremental area under the curve (iAUC). Plasma insulin responses were quantified via assays. Results: Compared to the SM, the MM significantly reduced the GLU_Peak (55%), GLU_P-N (35%), and 2 h iAUC (80%). Within the cohort, the MM elicited a 68% reduction in the GLU_Peak response compared to the SM in individuals with T2D. Insulin was lower following the MM (−62%). Participants reported similar subjective taste and mouthfeel ratings. Conclusion: A novel MM decreased PPG and insulin responses compared to a SM, without compromising taste, thus highlighting salient features for T2D nutrition management. Full article

Background/Objectives: Obesity and insulin resistance are increasing globally. Emerging evidence suggests that not only the quantity but also the source of dietary protein may improve metabolic health outcomes. This study evaluated the effects of high-protein diets (HPDs) containing animal or plant protein sources on obesity and obesity-related metabolic markers in a rodent model of genetic obesity. Methods: Obese male fa/fa Zucker rats were fed HPDs (35% of energy) containing protein from different sources (casein, egg white protein, soy + pea protein, mixture of egg white + soy + pea proteins) or a normal protein diet (15% of energy) containing casein over 8 weeks. Oral glucose tolerance, weight gain, fat depots, serum biochemistry, adipocyte and pancreatic islet size, and markers of adipose tissue lipolysis, insulin signaling, and immune cells were assessed. Results: Consumption of HPDs containing egg white protein, soy + pea, or their mixture resulted in smaller adipocytes compared to the casein diets, despite greater weight gain, elevated serum NEFA, and more total visceral fat in the HPD plant group. These HPD groups had reduced fasting insulin and no compensatory pancreatic islet enlargement. CD3 levels were elevated in adipose tissue without changes in F4/80, and no differences were observed in ATGL, HSL, Akt or AS160. Conclusions: The source of dietary protein in HPDs significantly influences metabolic outcomes in obese rats, impacting adipocyte and pancreatic islet size, insulinemia, and immune cell markers in adipose tissue. These findings support the potential of employing targeted dietary protein interventions for managing obesity-related metabolic disorders. Full article

Background/Objectives: Increased dehydroepiandrosterone sulfate (DHEAS) is used as a diagnostic marker of hyperandrogenism in women with polycystic ovary syndrome (PCOS). The mechanisms of adrenal hyperandrogenism in PCOS include hyperinsulinism as a potential stimulator, but results of studies associating insulinemia with DHEAS in PCOS are conflicting. The objective of this study was to evaluate the factors associated with DHEAS levels in PCOS, focusing on insulinemia. Methods: We performed a cross-sectional retrospective study in a total of 257 patients with PCOS (Rotterdam criteria) evaluated in our tertiary center of endocrinology. Clinical and biochemical parameters included body mass index (BMI), serum DHEAS, total testosterone and sex hormone-binding globulin (SHBG), insulin and glycaemia at fasting and 2 h during the oral glucose tolerance test (OGTT), and homeostasis model assessment for insulin resistance (HOMA-IR) was calculated. Results: The comparative analysis of PCOS divided into DHEAS tertiles revealed that patients in the upper tertile were younger (p < 0.05) and had higher 2 h insulin in the OGTT (p < 0.05) than the lower tertile, while fasting insulin and HOMA-IR were not different. DHEAS correlated negatively with age (r = −0.146, p < 0.05) and positively with 2 h insulinemia (r = 0.246, p < 0.001), while fasting insulin and HOMA-IR did not correlate with DHEAS in all PCOS. In stepwise linear regression models, 2 h insulin remained a positive independent predictor for DHEAS only in non-obese PCOS (p < 0.0001). Conclusions: Our data indicate a positive association between stimulated insulin and DHEAS in PCOS. Two-hour insulin in OGTT was an independent predictor of DHEAS in non-obese PCOS, suggesting that DHEAS might be a reliable marker for the stimulatory insulin effect on adrenal steroidogenesis in non-obese PCOS patients. Full article

With the prevalence of obesity and overweight increasing at an alarming rate, more and more researchers are focused on identifying effective weight loss strategies. The ketogenic diet (KD), used as a treatment in epilepsy management for over 100 years, is additionally gaining popularity as a weight loss method. Although its efficacy in weight loss is well documented, the areas where it may be beneficial to other dietary approaches need to be carefully examined. The objective of this paper is to identify the potential benefits of the KD over alternative dietary weight loss strategies based on a comprehensive literature review. It has been shown that the KD may be more bioenergetically efficient than other dietary strategies, inter alia owing to its effect on curtailing hunger, improving satiety and decreasing appetite (influence on hunger and satiety hormones and the sensation of hunger), inducing faster initial weight loss (associated with lower glycogen levels and reduced water retention), and controlling glycaemia and insulinemia (directly attributable to the low-carbohydrate nature of KD and indirectly to the other areas described). These effects are accompanied by improved insulin sensitivity, reduced inflammation (through ketone bodies and avoidance of pro-inflammatory sugars), reduced need for pharmacological obesity control (the diet’s mechanisms are similar to those of medication but without the side effects), and positive impacts on psychological factors and food addiction. Based on the authors’ review of the latest research, it is reasonable to conclude that, due to these many additional health benefits, the KD may be advantageous to other diet-based weight loss strategies. This important hypothesis deserves further exploration, which could be achieved by including outcome measures other than weight loss in future clinical trials, especially when comparing different diets of equal caloric value. Full article

Background: Advanced glycation end-products (AGEs) are linked to the development of oxidative stress, insulin resistance, and impaired insulin secretion. Adverse early life conditions, such as exposure to AGEs and their precursors, may lead offspring to the development of metabolic dysfunction in adulthood. Nonetheless, the early impact in offspring metabolism by maternal intake of AGEs precursors during lactation is not known. Objective: Investigate early life metabolism of the offspring whose breastfeeding dams were orally exposed to AGEs precursor. Methods: Breastfeeding Wistar rats were daily treated with the glycation precursor methylglyoxal (MG—60 mg/kg of bodyweight) by gavage or saline 0.9% control (CO) until weaning. In vivo glycemic homeostasis in male offspring was assessed, followed by euthanasia for tissue sample collection for ex vivo assessments. Results: At weaning, MG offspring presented decreased bodyweight (p < 0.05), perigonadal (p < 0.01) and retroperitoneal (p < 0.01) fat. MG offspring presented decreased glucose tolerance (p < 0.05), lower basal insulinemia (p < 0.001), reduced high-glucose static insulin secretion (p < 0.05), and reduced pancreatic islet area (p < 0.05). Accordingly, MG offspring pancreas showed lower GSH and SOD activity (p < 0.05; p < 0.001, respectively) and increased MPO (p < 0.05) activity. Conclusions: The consumption of AGE precursors by breastfeeding dams impaired offspring pancreatic function and glycemic homeostasis early in life. Full article

Background: Hypoglycemia in the case of persons without diabetes is a rare event, being usually, initially misinterpreted based on the symptoms that can mimic various diseases, especially of a neuro-psychiatric nature. In the case of the identification of insulin-mediated hypoglycemia, the evaluation of pancreatic neuroendocrine tumors, which represent the most common and worrisome causes of non-diabetic insulin-mediated hypoglycemia, must be considered. Case Report: We present the case of a 57-year-old patient, hospitalized for a history of approximately one month of recurrent episodes of symptoms suggestive for severe hypoglycemia. The biological evaluation performed during an episode of hypoglycemia showed a plasma glucose value of 44 mg/dL, insulinemia 16.3 µU/mL, C peptide 3.72 ng/mL, HbA1c 4.99%, absence of urinary ketone bodies and anti-insulin antibodies <0.03 U/mL. The CT and MRI examination showed a 15.3/15 mm rounded tumor in the pancreatic corporeo-caudal region. The pancreatic tumor formation was enucleated and the histopathological and immunohistochemical analysis confirmed the diagnosis of the pancreatic neuroendocrine tumor with a positive reaction for chromogranin A, synaptophysin and insulin, without malignancy features (Ki 67 positive in 1% of the tumor cells). The postoperative evolution was favorable, without episodes of hypoglycemia, the fasting insulinemia one day after surgery being 4.1 µU/mL and HbA1c at three weeks postoperatively being 5.51%. Conclusions: The management of patients with hyperinsulinemic hypoglycemia secondary to insulinoma involves multidisciplinary collaboration with an important role in recognizing symptoms suggestive of hypoglycemia in a person without diabetes, initiating biological and imaging evaluation, establishing the optimal therapeutic option and histopathological confirmation. Full article

Background/Objectives: There is controversy about the health risks of sugary diets. A recent study reported that chronic consumption of 11% sugar solutions improved glycemic control in lean mice. Based on this finding, we hypothesized that chronic consumption of the same 11% sugar solutions would also improve glycemic control in metabolically deranged mice. Methods: We exposed mice to a high-fat/high-sugar diet for 12 weeks. Then, we switched the mice to a control (i.e., standard chow) or one of four experimental diets for 8 weeks. The experimental diets contained standard chow plus an 11% solution of glucose or high-fructose syrup. The sugar syrups were derived from corn or cellulose. We included the cellulosic syrups because they contain polyphenols, which are thought to promote glycemic control. We measured body weight, adiposity, glucose tolerance, insulinemia, insulin sensitivity, body composition, and avidity for sweeteners. Results: Mice switched to the control diet lost weight, whereas mice switched to the experimental diets remained obese and hyperinsulinemic. Thus, the experimental diets did not cause the mice to regain normal metabolic health. Nevertheless, we observed (i) improvements in glucose tolerance in mice on both the control and experimental diets; (ii) reduced insulinemia and enhanced insulin sensitivity in mice offered the cellulosic syrups; (iii) elevations in cephalic-phase insulin responses in mice on the experimental diets; and (iv) increased avidity for sweeteners in mice on the control but not the experimental diets. Conclusions: Switching metabolically deranged mice to the experimental diets, particularly those with cellulosic sugars, improved glucose tolerance and insulin sensitivity. Full article

Both perinatal malnutrition and elevated glucocorticoids are pivotal triggers of the growing global pandemic of metabolic diseases. Here, we studied the effects of metabolic stress responsiveness on glucose–insulin homeostasis and pancreatic-islet function in male Wistar offspring whose mothers underwent protein restriction during lactation. During the first two weeks after delivery, lactating dams were fed a low-protein (4% protein, LP group) or normal-protein diet (22.5% protein, NP group). At 90 days of age, male rat offspring were challenged with food deprivation (72 h of fasting), intracerebroventricular (icv) injection of dexamethasone (2 µL, 2.115 mmol/L) or chronic intraperitoneal injection of dexamethasone (1 mg/kg body weight/5 days). Body weight, food intake, intravenous glucose tolerance test (ivGTT) results, insulin secretion and biochemical parameters were assessed. LP rats did not display significant metabolic changes after long-term starvation (p > 0.05) or under the central effect of dexamethasone (p = 0.999). Chronic dexamethasone induced rapid hyperglycemia (~1.2-fold, p < 0.001) and hyperinsulinemia (NP: 65%; LP: 216%; p < 0.001), decreased insulin sensitivity (NP: ~2-fold; LP: ~4-fold; p < 0.001), reduced insulinemia (20%) and increased glycemia (35%) only in NP rats under ivGTT conditions (p < 0.001). Glucose and acetylcholine insulinotropic effects, as well as the muscarinic receptor antagonist response, were reduced by chronic dexamethasone only in pancreatic islets from NP rats (p < 0.05). The direct effect of dexamethasone on pancreatic islets reduced insulin secretion (NP: 60.2%, p < 0.001; LP: 33.8%, p < 0.001). Peripheral glucose–insulin dyshomeostasis and functional failure of pancreatic islets in LP rats, as evidenced by an impaired acute and chronic response to metabolic stress, may be due to excessive corticosterone action as a long-term consequence. Full article

Background/Objectives: Goto-Kakizaki (GK) rats exhibit insulin resistance and type 2 diabetes mellitus (T2DM) without obesity. This study explored the effects of ω-3 fatty acid supplementation on T lymphocyte polarization in Wistar (WT) and GK rats. Methods: They were administered ω-3 fatty acid-rich fish oil (FO) containing eicosapentaenoic (540 mg/g) and docosahexaenoic acids (100 mg/g) by oral gavage at 2 g/kg, thrice a week for 8 weeks. The control groups (WT CT and GK CT) received the same volume of water. The following groups were investigated: GK CT, n = 14; GK ω-3, n = 15; Wistar CT, n = 15; and Wistar ω-3, n = 11. Glucose and insulin tolerance tests (GTT and ITT) were performed. Fasting plasma insulinemia and glycemia were measured. After euthanasia, the lymphocytes were extracted from the mesenteric lymph nodes. Results: The results showed that GK rats supplemented with FO had significantly improved glucose tolerance and insulin sensitivity (kITT). It also promoted greater polarization of lymphocytes toward T regulatory (Treg) features and a reduction in Th1 and Th17 profiles. Additionally, the GK ω-3 group exhibited lower cell proliferation, decreased pro-inflammatory cytokines, and increased IL-10 levels compared to the GK control. Conclusions: In conclusion, FO supplementation benefited GK rats by improving glucose intolerance, suppressing insulin resistance, and modulating lymphocytes toward Treg polarization. Full article

The epidemic of obesity has increased worldwide and is associated with comorbidities such as diabetes and cardiovascular disease. In this context, strategies that modulate body weight and improve glycemic metabolism have increased, and bariatric surgeries such as Sleeve Gastrectomy (SG) have been highlighted in obesity treatment. However, the mechanism by which SG reduces body weight and improves glycemic control remains unknown. Thus, in this study, we aimed to evaluate food intake and the expression of hypothalamic genes involved with the regulation of this process in diet-induced obese mice submitted to SG. For this, we used C57BL/6 mice submitted to a 10-week high-fat diet protocol and submitted to SG. Food intake, fed and fasted glycemia, as well as hypothalamic anorexigenic and orexigenic gene expression were evaluated 4 weeks after the surgical procedure. First, we observed that SG reduces body weight (44.19 ± 0.47 HFD, 43.51 ± 0.71 HFD-SHAM, and 38.22 ± 1.31 HFD-SG), fasting glycemia (115.0 ± 4.60 HFD, 122.4 ± 3.48 HFD-SHAM, and 93.43 ± 4.67 HFD-SG), insulinemia (1.77 ± 0.15 HFD, 1.92 ± 0.27 HFD-SHAM, and 0.93 ± 0.05 HFD-SG), and leptinemia (5.86 ± 1.38 HFD, 6.44 ± 1.51 HFD-SHAM, and 1.43 ± 0.35 HFD-SG) in obese mice. Additionally, SG reduces food (5.15 ± 0.18 HFD, 5.49 ± 0.32, HFD-SHAM, and 3.28 ± 0.26 HFD-SG) and total (16.88 ± 0.88 HFD, 17.05 ± 0.42, HFD-SHAM, and 14.30 ± 0.73 HFD-SG) calorie intake without alterations in anorexigenic and orexigenic gene expression. In conclusion, these data indicate that SG improves obesity-associated alterations at least in part by a reduction in food intake. This effect is not associated with the canonical food intake pathway in the hypothalamus, indicating the involvement of non-canonical pathways in this process. Full article

Obesity is a multifactorial disease that is difficult to control worldwide. Although nuts are recognized health foods, the application of food in obesity management is unclear. We systematically reviewed the literature and performed a meta-analysis to evaluate if nut consumption favors people on energy restriction (ER) dietary interventions. Four databases were used to search for eligible articles in May 2024. This review was conducted according to the PRISMA guide, and the bias risk of papers was evaluated. For the meta-analysis, we extracted the endpoint values of the group’s variables and estimated the effect sizes by the random-effects model. Sixteen and ten articles were included in the systematic review and meta-analysis, respectively. Almonds were evaluated in the majority of studies (n = 6). The consumption of nuts (28 to 84 g/d, 4 to 72 months) included in ER (–250 to 1000 kcal/d) did not differently affect anthropometry (weight loss, BMI, waist and hip circumferences), body composition (fat mass, fat-free mass, or lean mass), markers of glucose (glycemia and insulinemia), lipid metabolism (total cholesterol, HDL-c, LDL-c, LDL-c/HDL-c, or triglycerides), and systolic and diastolic blood pressure. In most analyses, stratifying studies by type of nut or intervention time did not present different results in the meta-analysis. As there are few studies, in addition to great methodological variability, more high-quality trials are needed to confirm these results. The PROSPERO registration number is CRD42023444878. Full article

Background. The rise in global obesity has worsened the prevalence of metabolic syndrome and related cardiovascular complications, particularly among post-menopausal women. Dysfunctions in thyroid hormone activity, critical for metabolic regulation, are often implicated in obesity and its associated conditions. This study evaluated the interactions between thyroid function, body composition, and cardiovascular health in post-menopausal women. Material and Methods. We conducted an observational, prospective, open-label clinical study, involving post-menopausal women, stratified into two groups based on weight changes after menopause: the Menopausal Weight Gain Group (MWGG) and the Menopausal Weight Maintenance Group (MWMG). We included 12 cases (MWGG) and 8 control (MWMG) women. Participants underwent cardio-metabolic assessments, including evaluations of thyroid function, blood pressure, arterial stiffness, body composition, and cardiovascular risk profiles. The statistical analysis employed t-tests and Pearson correlations. Results. The MWGG showed significant increases in both the Augmentation Index (AI@75) and adiposity markers (BMI, total fat mass, in percentage and kg, and lean–to–fat mass ratio) compared to the MWMG. A notable decrease in FT3 and the FT3/FT4 ratio was observed in the MWGG. Moreover, discrepancies in Cholesterol levels and insulinemia were reported between groups. Moreover, differences in cholesterol levels and insulinemia were reported between groups. We analyzed the correlation between blood pressure, cardiovascular stiffness, and body composition parameters; notably, there was a strong correlation between AI@75 and weight, BMI, and total fat mass, and a strong negative correlation with the lean–to–fat mass ratio. Conclusions. The MWGG presented a higher BMI, greater total fat mass (kg) and a higher percentage of total fat mass compared to the MWMG. Interestingly, we reported a significant difference in intramuscular adipose tissue between the groups. These results highlight the importance of further research to elucidate the mechanisms involved and to develop targeted interventions for managing menopause-related cardio-metabolic risks. Full article

The fruit of the cashew, a tree belonging to the family Anacardiaceae, is composed of approximately 10% nut (cashew) and 90% stalk or pseudofruit, usually discarded in situ and fermented in the soil. This review identifies cashew pseudofruit’s physicochemical characteristics and bioactive compounds and their possible relationship to health benefits. Different processing techniques have been used to preserve the pseudofruit, and the effect of these techniques on its nutrients is also reviewed in this work. Cashew is a highly perishable product with moisture content above 80% w/w and 10% w/w sugars. It also has a high content of polyphenols, flavonoids, and tannins and high antioxidant properties that are best preserved by nonthermal processing techniques. The pseudofruit presents the high inhibitory activity of α-amylase and lipase enzymes, has anti-inflammatory and body weight reduction properties and healing activity, and controls glucose levels, insulinemia, and insulin resistance. For all these reasons, cashews have been promoted as a propitious food/ingredient for preventive and therapeutic management of different pathologies such as diabetes, dyslipidemia, obesity, hypertension, fatty liver, and acne. Moreover, it has positive effects on the intestinal microflora, among others. This pseudofruit has a high potential for the development of functional foods. Full article