Dietary fat, insulin sensitivity and the metabolic syndrome

1-DNJ Alleviates Obesity-Induced Testicular Inflammation in Mice Model by Inhibiting IKKβ/ NF-kB Pathway

Obesity is associated with chronic inflammation that affects various organs in the body, including the reproductive system, which is a key factor in male infertility. 1-Deoxynojirimycin (1-DNJ) is a natural alkaloid in mulberry leaves, which has anti-inflammatory capabilities, yet, it's effects on obesity-induced inflammation-related male infertility remain unclear. Therefore, this research investigates the underlying mechanism by which 1-DNJ may mitigate fertility impairment in male mice caused by obesity-related inflammation. Male mice with high-fat diet (HFD)-induced obesity were treated with 1-DNJ or metformin for 8 weeks. Metabolic profiles were evaluated by enzyme method. Reproductive capacity was assessed by sperm viability, motility and counts, immunohistochemistry was performed to evaluate the testicular damage caused by obesity and inflammation. The inflammation was assessed by measuring the levels of tumor necrosis factor α (TNFα), interleukin 1β (IL-1β), and interleukin 6 (IL-6). The activation of IκB kinase β (IKKβ) and nuclear factor κB (NF-κB) was examined using western blot and immunohistochemistry. HFD induced obesity in mice with obvious lipid metabolism disorder. The obese male mice had a decreased testosterone level, impaired sperm motility, and increased inflammatory factors. 1-DNJ treatment improved the testosterone level in the obese mice, ameliorated the testicular structure damage and improve sperm viability. In addition, 1-DNJ treatment inhibited IKKβ/NF-kB signaling pathway and reduced inflammation in obese mice. 1-DNJ can improve the fertility of obese men by reducing obesity as well as obesity-induced inflammation. These findings provide new insights for 1-DNJ to alleviate inflammation caused by obesity and provide future possibilities for treating male infertility.

Liver phospholipid fatty acid composition in response to chronic high-fat diets

Liver phospholipid fatty acid composition depends on the dietary lipid intake and the efficiency of hepatic enzymatic activity. Our study aimed to simultaneously investigate the liver phospholipid fatty acid composition in response to chronic linseed, palm, or sunflower oil diets. We used adult female C57/BL6 mice and randomly divided them into control and three groups treated with 25 % dietary oils. Prior to treatment, we analyzed the fatty acid profiles in dietary oils and hepatocytes and, after 100 days, the fatty acid composition in the liver using gas-liquid chromatography. Linseed oil treatment elevated alpha-linolenic, eicosapentaenoic, and docosapentaenoic acids and reduced arachidonic and docosatetraenoic acids, consequently lowering the n-6/n-3 ratio. Palm oil treatment increased linoleic acid and decreased docosahexaenoic acid, contributing to an elevated n-6/n-3 ratio. Sunflower oil treatment elevated total monounsaturated fatty acids by increasing palmitoleic, oleic, and vaccenic acids. The estimated activity of Δ9 desaturase was significantly elevated in the sunflower oil group, while Δ5 desaturase was the highest, and Δ6 desaturase was the lowest after the linseed oil diet. Our findings demonstrate that chronic consumption of linseed, palm, or sunflower oil alters the distribution of liver phospholipid fatty acids differently. Sunflower oil diet elevated total monounsaturated fatty acids, proposing potential benefits for liver tissue health. Considering these outcomes, a substantial recommendation emerges to elevate linseed oil intake, recognized as the principal ALA source, thereby aiding in reducing the n-6/n-3 ratio. Moreover, modifying dietary habits to incorporate specific vegetable oils in daily consumption could substantially enhance overall health.

A whole-food, plant-based randomized controlled trial in metastatic breast cancer: weight, cardiometabolic, and hormonal outcomes

PURPOSE

Breast cancer treatment is associated with weight gain, and obesity and its related cardiometabolic and hormonal risk factors have been associated with poorer outcomes. Dietary intervention may address these risk factors, but limited research has been done in the setting of metastatic breast cancer requiring systemic therapy.

METHODS

Women with metastatic breast cancer on stable treatment were randomized 2:1 to an 8-week intervention (n = 21) or control (n = 11). The intervention included weekly assessment visits and an ad libitum whole-food, plant-based (WFPB) diet with provided meals. Cardiometabolic, hormonal, and cancer markers were assessed at baseline, 4 weeks, and 8 weeks.

RESULTS

Within the intervention group, mean weight decreased by 6.6% (p < 0.01) after 8 weeks. Fasting insulin decreased from 16.8 uIU/L to 11.2 uIU/L (p < 0.01), concurrent with significantly reduced insulin resistance. Total cholesterol decreased from 193.6 mg/dL to 159 mg/dL (p < 0.01), and low-density lipoprotein (LDL) cholesterol decreased from 104.6 mg/dL to 82.2 mg/dL (p < 0.01). Total testosterone was unchanged, but free testosterone trended lower within the intervention group (p = 0.08) as sex hormone binding globulin increased from 74.3 nmol/L to 98.2 nmol/L (p < 0.01). There were no significant differences in cancer progression markers at week 8, although mean CA 15-3, CA 27.29, and CEA were lower in the intervention group (p = 0.53, p = 0.23, and p = 0.54, respectively) compared to control, when adjusted for baseline.

CONCLUSION

WFPB dietary changes during treatment for metastatic breast cancer are well tolerated and significantly improve weight, cardiometabolic and hormonal parameters. Longer studies are warranted to assess the durability of changes. Trial registration First registered at Clinicaltrials.gov (NCT03045289) on February 7, 2017.

Machine Learning Identification of Nutrient Intake Variations across Age Groups in Metabolic Syndrome and Healthy Populations

This study undertakes a comprehensive examination of the intricate link between diet nutrition, age, and metabolic syndrome (MetS), utilizing advanced artificial intelligence methodologies. Data from the National Health and Nutrition Examination Survey (NHANES) spanning from 1999 to 2018 were meticulously analyzed using machine learning (ML) techniques, specifically extreme gradient boosting (XGBoost) and the proportional hazards model (COX). Using these analytic methods, we elucidated a significant correlation between age and MetS incidence and revealed the impact of age-specific dietary patterns on MetS. The study delineated how the consumption of certain dietary components, namely retinol, beta-cryptoxanthin, vitamin C, theobromine, caffeine, lycopene, and alcohol, variably affects MetS across different age demographics. Furthermore, it was revealed that identical nutritional intakes pose diverse pathogenic risks for MetS across varying age brackets, with substances such as cholesterol, caffeine, and theobromine exhibiting differential risks contingent on age. Importantly, this investigation succeeded in developing a predictive model of high accuracy, distinguishing individuals with MetS from healthy controls, thereby highlighting the potential for precision in dietary interventions and MetS management strategies tailored to specific age groups. These findings underscore the importance of age-specific nutritional guidance and lay the foundation for future research in this area.

Beneficial Effects of Capybara Oil Supplementation on Steatosis and Liver Apoptosis in Obese Mice

Obesity is a complex chronic disease characterized by excess body fat (adipose) that is harmful to health and has been a major global health problem. It may be associated with several diseases, such as nonalcoholic fatty liver disease (NAFLD). Polyunsaturated fatty acids (PUFA) are lipid mediators that have anti-inflammatory characteristics and can be found in animals and plants, with capybara oil (CO) being a promising source. So, we intend to evaluate the hepatic pathophysiological alterations in C57Bl/6 mice with NAFLD, caused by obesity, and the possible beneficial effects of OC in the treatment of this disease. Eighteen 3-month-old male C57Bl/6 mice received a control or high-fat diet for 18 weeks. From the 15th to the 18th week, the animals received treatment-through orogastric gavage-with placebo or free capybara oil (5 g/kg). Parameters inherent to body mass, glucose tolerance, evaluation of liver enzymes, percentage of hepatic steatosis, oxidative stress, the process of cell death with the apoptotic biomarkers (Bax, Bcl2, and Cytochrome C), and the ultrastructure of hepatocytes were analyzed. Even though the treatment with CO was not able to disassemble the effects on the physiological parameters, it proved to be beneficial in reversing the morphological and ultrastructural damage present in the hepatocytes. Thus, demonstrating that CO has beneficial effects in reducing steatosis and the apoptotic pathway, it is a promising treatment for NAFLD.

Differential Associations of Erythrocyte Membrane Saturated Fatty Acids with Glycemic and Lipid Metabolic Markers in a Chinese Population: A Cross-Sectional Study

Mounting evidence indicates a complex link between circulating saturated fatty acids (SFAs) and cardiovascular disease (CVD) risk factors, but research on erythrocyte membrane SFA associations with metabolic markers remains limited. Our study sought to investigate the correlations between erythrocyte membrane SFAs and key metabolic markers within glycemic and lipid metabolism in a Chinese population of 798 residents aged 41 to 71 from Guangzhou. Using gas chromatography-mass spectrometry, we assessed the erythrocyte membrane saturated fatty acid profile and performed multiple linear regression to evaluate the relationship between different SFA subtypes and metabolic markers. Our findings revealed that the odd-chain SFA group (C15:0 + C17:0) exhibited negative associations with fasting blood glucose (FBG), homeostatic model assessment for insulin resistance (HOMA-IR), and triglycerides (TG). Conversely, the very-long-chain SFA group (C20:0 + C22:0 + C23:0 + C24:0) exhibited positive associations with fasting insulins (FINS), HOMA-IR, total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C). Furthermore, there was no evidence supporting an association between the even-chain group (C14:0 + C16:0 + C18:0) and metabolic markers. Our findings suggest that different subtypes of SFAs have diverse effects on glycemic and lipid metabolic markers, with odd-chain SFAs associated with a lower metabolic risk. However, the results concerning the correlations between even-chain SFAs and very-long-chain SFAs with markers of glycemic and lipid metabolism pathways are confusing, highlighting the necessity for further exploration and investigation.

High Fat Diet-Wheat Gliadin Interaction and its Implication for Obesity and Celiac Disease Onset: In Vivo Studies

The intestinal immune system plays a crucial role in obesity and insulin resistance. An altered intestinal immunity is associated with changes to the gut microbiota, barrier function, and tolerance to luminal antigens. Lipid metabolism and its unbalance can also contribute to acute and chronic inflammation in different conditions. In celiac disease (CD), the serum phospholipid profile in infants who developed CD is dramatically different when compared to that of infants at risk of CD not developing the disease. In a mouse model of gluten sensitivity, oral wheat gliadin challenge in connection with inhibition of the metabolism of arachidonic acid, an omega-6 polyunsaturated fatty acid, specifically induces the enteropathy. Recent evidence suggests that gluten may play a role also for development of life-style related diseases in populations on a high fat diet (HFD). However, the mechanisms behind these effects are not yet understood. Exploratory studies in mice feed HFD show that wheat gliadin consumption affects glucose and lipid metabolic homeostasis, alters the gut microbiota, and the immune cell profile in liver.

The Effects of Body Fat Reduction through the Metabolic Control of Steam-Processed Ginger Extract in High-Fat-Diet-Fed Mice

The prevalence of metabolic syndrome is increasing globally due to behavioral and environmental changes. There are many therapeutic agents available for the treatment of chronic metabolic diseases, such as obesity and diabetes, but the data on their efficacy and safety are lacking. Through a pilot study by our group, Zingiber officinale rhizomes used as a spice and functional food were selected as an anti-obesity candidate. In this study, steam-processed ginger extract (GGE) was used and we compared its efficacy at alleviating metabolic syndrome-related symptoms with that of conventional ginger extract (GE). Compared with GE, GGE (25-100 μg/mL) had an increased antioxidant capacity and α-glucosidase inhibitory activity in vitro. GGE was better at suppressing the differentiation of 3T3-L1 adipocytes and lipid accumulation in HepG2 cells and promoting glucose utilization in C2C12 cells than GE. In 16-week high-fat-diet (HFD)-fed mice, GGE (100 and 200 mg/kg) improved biochemical profiles, including lipid status and liver function, to a greater extent than GE (200 mg/kg). The supplementation of HFD-fed mice with GGE (200 mg/kg) resulted in the downregulation of SREBP-1c and FAS gene expression in the liver. Collectively, our results indicate that GGE is a promising therapeutic for the treatment of obesity and metabolic syndrome.

Role of Dietary Macronutrient Composition and Fibre Intake in Development of Double Diabetes in Indian Youth

Introduction

Insulin resistance (IR) and obesity are common presentations of double diabetes (DD) in subjects with type-1 diabetes (T1D). There is evidence that dietary composition has an impact on developing IR. Objectives were to assess the impact of macronutrient and fibre intake on glycaemic control and the role of macronutrient composition of diet in the development of DD in subjects with T1D.

Methods

This cross-sectional study included 77 young adults (10-25 years) with T1D. Data related to demography, anthropometry, biochemistry and body composition were collected. Dietary data was collected by fourteen-day food diary. IR was calculated using eGDR, SEARCH and CACTI equations, and metabolic syndrome (MS) was diagnosed using the International Diabetes Federation Consensus Definition.

Results

Subjects at risk of DD had higher age, leptin levels, percentage carbohydrate consumption in diet and IR. A positive association of insulin sensitivity with fibre intake and %protein intake was noted. Poor glycaemic control, adiponectin/leptin ratio, fibre intake and insulin/carbohydrate ratio were significant negative predictors of IR. Addition of dietary factors to the regression model improved the R square and percentage of subjects identified correctly. Inclusion of dietary parameters significantly improves the prediction of the risk of development of DD in subjects with T1D.

Conclusion

Good glycaemic control and increased intake of dietary fibre may prevent the development of IR in subjects with T1D and reduce the burden of DD.

Nutrient patterns in relation to insulin resistance and endothelial dysfunction in Iranian women

Prior studies have mainly focused on the association of one specific nutrient with insulin resistance (IR) and endothelial dysfunction and limited studies have assessed the association with different nutrient patterns (NPs). We examined the association between various NPs and IR and endothelial dysfunction among Iranian women. This cross-sectional study was carried out on a sample of 368 female nurses. A 106-items food frequency questionnaire (FFQ) was applied for dietary assessments. Using factor analysis, the relationships between NPs and markers of insulin resistance (HOMA-IR, HOMA-β, and QUICKY), and endothelial dysfunction (E-selectin, sICAM-1, and sVCAM-1) were assessed. Mean age and body mass index of participants were respectively 35.21 years and 24.04 kg/m2. Three major NPs were identified. NP1, named as "dairy, fruits, and vegetables" had high values of potassium, folate, vitamins A and C, magnesium, and beta carotene. No significant association was observed between this NP and insulin resistance or endothelial dysfunction indices. The second NP was full of chromium, selenium, copper, vitamin B6, monounsaturated fatty acid (MUFA), thiamin, vitamin D, and iron. Adherence to NP2 (named "legumes, nuts, and protein foods") was associated with lower values of insulin (6.8 ± 1.1 versus 8.4 ± 1.1, P = 0.01), homeostasis model assessment-Insulin resistance (HOMA-IR) (1.3 ± 0.2 versus 1.7 ± 0.2, P = 0.02), and vascular adhesion molecule 1 (VCAM-1) (444.2 ± 27.9 versus 475.8 ± 28.4, P = 0.03). However, adherence to the third NP, rich in saturated fatty acid (SFA), cholesterol, sodium, zinc, vitamin E, and B12, described as "animal fat and meat + vitamin E", was associated with higher amounts of homeostasis model assessment-β (HOMA-β) (531.3 ± 176.2 versus 48.7 ± 179.8, P = 0.03). In conclusion, following the NP2, correlated with higher intakes of chromium, selenium, copper, vitamin B6, MUFA and thiamin was associated with lower values of insulin, HOMA-IR, and sVCAM-1. Adherence to NP3, rich in SFA, cholesterol, vitamin E, vitamin B12, and zinc was associated with higher levels of HOMA-β.

Interesterified palm oil promotes insulin resistance and altered insulin secretion and signaling in Swiss mice

Interesterified fats have been used to replace trans-fat in ultra-processed foods. However, their metabolic effects are not completely understood. Hence, this study aimed to investigate the effects related to glucose homeostasis in response to interesterified palm oil or refined palm oil intake. Four-week-old male Swiss mice were randomly divided into four experimental groups and fed the following diets for 8 weeks: a normocaloric and normolipidic diet containing refined palm oil (PO group) or interesterified palm oil (IPO group); a hypercaloric and high-fat diet containing refined PO (POHF group) or interesterified PO (IPOHF group). Metabolic parameters related to body mass, adiposity and food consumption showed no significant differences. As for glucose homeostasis parameters, interesterified palm oil diets (IPO and IPOHF) resulted in higher glucose intolerance than unmodified palm oil diets (PO and POHF). Euglycemic-hyperinsulinemic clamp assessment showed a higher endogenous glucose production in the IPO group compared with the PO group. Moreover, the IPO group showed significantly lower p-AKT protein content (in the muscle and liver tissues) when compared with the PO group. Analysis of glucose-stimulated static insulin secretion (11.1 mmol/L glucose) in isolated pancreatic islets showed a higher insulin secretion in animals fed interesterified fat diets (IPO and IPOHF) than in those fed with palm oil (PO and POHF). Interesterified palm oil, including in normolipidic diets, can impair insulin signaling in peripheral tissues and increase insulin secretion by β-cells, characterizing insulin resistance in mice.

Avocado intake and cardiometabolic risk factors in a representative survey of Australians: a secondary analysis of the 2011-2012 national nutrition and physical activity survey

BACKGROUND

Avocados are a rich source of nutrients including monounsaturated fats, dietary fibre and phytochemicals. Higher dietary quality is reported in studies of consumers with higher avocado intakes. The present study aimed to examine avocado consumption and cardiometabolic risk measures in a representative sample of Australian adults.

METHODS

A cross-sectional analysis was performed using Australian Health Survey 2011-2013 (n = 2,736 observations). Day 1 24-hour recall data was used to examine reported avocado intake (whole avocados and avocado-containing products excluding avocado oil) and cardiometabolic risk measures (LDL, HDL, and total cholesterol, triglycerides, apolipoprotein B, HbA1c, plasma glucose, systolic and diastolic blood pressure). T-tests and chi square analyses were conducted between low (5.21 [95% CI: 4.63, 5.79] grams/day) and high (44.11 [95% CI: 35.89, 52.33] grams/day) consumers of avocado.

RESULTS

14.7% of Australians were 'avocado consumers' (n = 403 observations). Mean avocado intake was 24.63 (95% CI: 20.11, 29.15) grams per day, with a median intake of 10.40 (IQR: 4.49-26.00) grams per day for those considered 'avocado consumers'. Consumers of avocados had a lower BMI and waist circumference (each, p ≤ 0.001), lower plasma glucose level (p = 0.03), and higher HDL cholesterol (p ≤ 0.001) when compared with non-consumers. A trend towards lower plasma glucose, HbA1c (each, p = 0.04) and higher dietary fibre intake (p = 0.05) was found between high and low consumers of avocado.

CONCLUSIONS

Our study suggests favourable outcomes for avocado intake and cardiometabolic characteristics of consumers. Future studies should explore glucose homeostasis using a clinical trial design to understand potential relationships between avocado intake and cardiometabolic risk factors.

Tryptophanylation of insulin receptor by WARS attenuates insulin signaling

Increased circulating amino acid levels have been linked to insulin resistance and development of type 2 diabetes (T2D), but the underlying mechanism remains largely unknown. Herein, we show that tryptophan modifies insulin receptor (IR) to attenuate insulin signaling and impair glucose uptake. Mice fed with tryptophan-rich chow developed insulin resistance. Excessive tryptophan promoted tryptophanyl-tRNA synthetase (WARS) to tryptophanylate lysine 1209 of IR (W-K1209), which induced insulin resistance by inhibiting the insulin-stimulated phosphorylation of IR, AKT, and AS160. SIRT1, but not other sirtuins, detryptophanylated IRW-K1209 to increase the insulin sensitivity. Collectively, we unveiled the mechanisms of how tryptophan impaired insulin signaling, and our data suggested that WARS might be a target to attenuate insulin resistance in T2D patients.

LRRK2 negatively regulates glucose tolerance via regulation of membrane translocation of GLUT4 in adipocytes

Epidemiological studies have shown that abnormalities of glucose metabolism are involved in leucine-rich repeat kinase 2 (LRRK2)-associated Parkinson's disease (PD). However, the physiological significance of this association is unclear. In the present study, we investigated the effect of LRRK2 on high-fat diet (HFD)-induced glucose intolerance using Lrrk2-knockout (KO) mice. We found for the first time that HFD-fed KO mice display improved glucose tolerance compared with their wild-type (WT) counterparts. In addition, high serum insulin and leptin, as well as low serum adiponectin resulting from HFD in WT mice were improved in KO mice. Using western blotting, we found that Lrrk2 is highly expressed in adipose tissues compared with other insulin-related tissues that are thought to be important in glucose tolerance, including skeletal muscle, liver, and pancreas. Lrrk2 expression and phosphorylation of its kinase substrates Rab8a and Rab10 were significantly elevated after HFD treatment in WT mice. In cell culture experiments, treatment with a LRRK2 kinase inhibitor stimulated insulin-dependent membrane translocation of glucose transporter 4 (Glut4) and glucose uptake in mouse 3T3-L1 adipocytes. We conclude that increased LRRK2 kinase activity in adipose tissue exacerbates glucose tolerance by suppressing Rab8- and Rab10-mediated GLUT4 membrane translocation.

A Whole-Food, Plant-Based Randomized Controlled Trial in Metastatic Breast Cancer: Weight, Cardiometabolic, and Hormonal Outcome

Purpose

Breast cancer treatment is associated with weight gain, and obesity and its related cardiometabolic and hormonal risk factors have been associated with poorer outcomes. Dietary intervention may address these risk factors, but limited research has been done in the setting of metastatic breast cancer requiring systemic therapy.

Methods

Women with metastatic breast cancer on stable treatment were randomized 2:1 to an 8-week intervention (n = 21) or control (n = 11). The intervention included weekly assessment visits and an ad libitum whole food, plant-based (WFPB) diet with provided meals. Cardiometabolic, hormonal, and cancer markers were assessed at baseline, 4 weeks, and 8 weeks.

Results

Within the intervention group, mean weight decreased by 6.6% (p < 0.01) after 8 weeks. Fasting insulin decreased from 16.8 uIU/L to 11.2 uIU/L (p < 0.01), concurrent with significantly reduced insulin resistance. Total cholesterol decreased from 193.6 mg/dL to 159 mg/dL (p < 0.01) and low-density lipoprotein (LDL) cholesterol decreased from 104.6 mg/dL to 82.2 mg/dL (p < 0.01). Total testosterone was unchanged, but free testosterone trended lower within the intervention group (p = 0.08) as sex hormone binding globulin increased from 74.3 nmol/L to 98.2 nmol/L (p < 0.01). There were no significant differences in cancer progression markers at week 8, although mean CA 15 - 3, CA 27.29, and CEA were lower in the intervention group (p = 0.53, p = 0.23, and p = 0.54, respectively) compared to control, when adjusted for baseline.

Conclusion

WFPB dietary changes during treatment for metastatic breast cancer are well tolerated and significantly improve weight and cardiometabolic and hormonal parameters. Longer studies are warranted to assess the durability of changes.

Trial registration

First registered at Clinicaltrials.gov (NCT03045289) on February 7, 2017.

Dairy foods and cardiometabolic diseases: an update and a reassessment of the impact of SFA

Type 2 diabetes (T2D) and CVD are major causes of mortality and chronic morbidity. Whilst mortality from CVD has decreased they remain the largest cause of death in Europe and the prevalence of T2D is increasing rapidly. A consistent component of public health advice is to reduce intake of SFA to reduce CVD in particular, which implies limiting dairy food consumption. The prospective studies and randomised controlled trials included in this review show that for dairy foods at least, SFA are not consistently associated with CVD or T2D risk. For CVD the association with dairy foods is generally neutral despite dairy foods being the major source of SFA in many diets. This creates considerable doubt, at least for dairy foods, concerning the validity of the traditional diet-heart hypothesis which positively relates SFA intake to increased serum LDL-cholesterol and subsequent increased CVD. There is now emerging evidence to explain this which is highly relevant to dairy foods. These include the potentially counterbalancing effect of SFA-stimulated HDL-cholesterol and specific food matrix factors. In addition, SFA are associated with the less atherogenic large buoyant LDL particles and possible counterbalancing hypotensive effects of dairy proteins. Overall, dairy foods have either a neutral or beneficial association with CVD and T2D. Beneficial associations are seen for blood pressure and the reduced T2D risk linked to yoghurt consumption, a subject that needs urgent attention given the sharp rise in T2D prevalence in many countries.

The acute effects of a DASH diet and whole food, plant-based diet on insulin requirements and related cardiometabolic markers in individuals with insulin-treated type 2 diabetes

AIMS

There is limited research regarding insulin dosing changes following adoption of plant-based diets. We conducted a nonrandomized crossover trial utilizing two plant-based diets (Dietary Approaches to Stop Hypertension, or DASH, and Whole Food, Plant-Based, or WFPB) to assess acute changes in insulin requirements and associated markers among individuals with insulin-treated type 2 diabetes.

METHODS

Participants (n = 15) enrolled in a 4-week trial with sequential, one-week phases: Baseline, DASH 1, WFPB, and DASH 2. Each diet was ad libitum and meals were provided.

RESULTS

Compared to baseline, daily insulin usage was 24%, 39%, and 30% lower after DASH 1, WFPB, and DASH 2 weeks respectively (all p < 0.01). Insulin resistance (HOMA-IR) was 49% lower (p < 0.01) and the insulin sensitivity index was 38% higher (p < 0.01) at the end of the WFPB week before regressing toward baseline during DASH 2. Total, LDL, and HDL cholesterol, leptin, urinary glucose, and hsCRP decreased to a nadir at the end of the WFPB week before increasing during DASH 2.

CONCLUSIONS

Adopting a DASH or WFPB diet can result in significant, rapid changes in insulin requirements, insulin sensitivity, and related markers among individuals with insulin-treated type 2 diabetes, with larger dietary changes producing larger benefits.

Effect of Omega-3 Rich High-Fat Diet on Markers of Tissue Lipid Metabolism in Glucocorticoid-Treated Mice

Glucocorticoids (GCs) are some of the most widely prescribed therapies for treating numerous inflammatory diseases and multiple cancer types. With chronic use, GCs' therapeutic benefits are concurrent with deleterious metabolic side effects, which worsen when combined with a high-fat diet (HFD). One characteristic of the common Western HFD is the presence of high omega-6 polyunsaturated fatty acids (PUFAs) and a deficiency in omega-3 PUFAs. The aim of this experiment was to determine whether fat composition resulting from HFD affects glucocorticoid-induced alterations in lipid-handling by the liver and skeletal muscle. Male wild-type C57BL/6 mice were randomized into two groups: n-6 (45% fat 177.5 g lard) and n-3 (45% fat 177.5 g Menhaden oil). After 4 weeks on their diets, groups were divided to receive either daily injections of dexamethasone (3 mg/kg/day) or sterile PBS for 1 week while continuing diets. The n-3 HFD diet attenuated adipose and hepatic fatty accumulation and prevented GC-induced increases in liver lipid metabolism markers Cd36 and Fabp. N-3 HFD had little effect on markers of lipid metabolism in oxidative and glycolytic skeletal muscle and was unable to attenuate GC-induced gene expression in the muscle. The present study's result demonstrated that the change of fat composition in HFD could beneficially alter the fatty acid accumulation and associated lipid metabolism markers in mice treated with dexamethasone.

Diet and metabolic syndrome: a narrative review

Metabolic syndrome (MetS) is a highly prevalent condition defined by the presence of at least three out of five risk factors including central obesity, increased fasting glucose, high blood pressure, and dyslipidaemia. Metabolic syndrome is associated with a 2-fold increase in cardiovascular outcomes and a 1.5-fold increase in all-cause mortality. Excess energy intake and Western dietary pattern may influence the development of metabolic syndrome. By contrast, both Mediterranean diet (Med-diet) and Dietary Approaches to Stop Hypertension (DASH) diet, with or without calorie restriction, have positive effects. For the prevention and management of MetS, it is recommended to increase the daily intake of fiber-rich and low-glycaemic-index foods and the consumption of fish and dairy products, especially yogurt and nuts. Moreover, it is advisable to consume a large variety of unprocessed cereals, legumes, and fruit. Finally, it is suggested to replace saturated fatty acids with monounsaturated and polyunsaturated fatty acids and to limit the consumption of free sugars to less than 10% of the total energy intake. The aim of this narrative review is to analyze current evidence on the different dietary patterns and nutrients that may affect prevention and treatment of MetS and to discuss the underlying pathophysiological mechanisms.

Effect of High Fat Diet on Disease Development of Polycystic Ovary Syndrome and Lifestyle Intervention Strategies

Polycystic ovary syndrome (PCOS) is a prevalent endocrine and metabolic disorder that affects premenopausal women. The etiology of PCOS is multifaceted, involving various genetic and epigenetic factors, hypothalamic-pituitary-ovarian dysfunction, androgen excess, insulin resistance, and adipose-related mechanisms. High-fat diets (HFDs) has been linked to the development of metabolic disorders and weight gain, exacerbating obesity and impairing the function of the hypothalamic-pituitary-ovarian axis. This results in increased insulin resistance, hyperinsulinemia, and the release of inflammatory adipokines, leading to heightened fat synthesis and reduced fat breakdown, thereby worsening the metabolic and reproductive consequences of PCOS. Effective management of PCOS requires lifestyle interventions such as dietary modifications, weight loss, physical activity, and psychological well-being, as well as medical or surgical interventions in some cases. This article systematically examines the pathological basis of PCOS and the influence of HFDs on its development, with the aim of raising awareness of the connection between diet and reproductive health, providing a robust approach to lifestyle interventions, and serving as a reference for the development of targeted drug treatments.

Effects of high-grain diet feeding on fatty acid profiles in milk, blood, muscle, and adipose tissue, and transcriptional expression of lipid-related genes in muscle and adipose tissue of dairy cows

BACKGROUND

High-grain (HG) diets affect lipid metabolism in the liver and mammary tissue of dairy cows, but its effects on muscle and adipose tissue have not been wide evaluated. Thus, the aim of this study is to clarify this issue.

METHODS

Twelve Holstein cows were randomly divided into two groups: conventional diet group (CON, n = 6) and the HG diet group (n = 6). On day 7 of week 4, rumen fluid was sampled to measure pH, milk was sampled to measure components, and blood was sampled to measure biochemical parameters and fatty acid composition. After the experiment, cows were slaughtered to collect muscle and adipose tissue for fatty acid composition and transcriptome analysis.

RESULTS

HG feeding decreased the ruminal pH, milk's fat content and long-chain fatty acid proportion (P < 0.05) and increased the proportion of short- and medium-chain fatty acids in the milk (P < 0.05) as compared with CON diets. The concentrations of blood cholesterol, low-density lipoprotein, and polyunsaturated fatty acids in the HG cows were lower than those in CON cows (P < 0.05). In muscle tissue, HG feeding tended to increase the triacylglycerol (TG) concentration (P < 0.10). Transcriptome analysis revealed changes in the biosynthesis of the unsaturated fatty acids pathway, the regulation of lipolysis in the adipocytes pathway, and the PPAR signalling pathway. In adipose tissue, HG feeding increased the concentration of TG and decreased the concentration of C18:1 cis9 (P < 0.05). At the transcriptome level, the fatty acid biosynthesis pathway, linoleic acid metabolism pathway, and PPAR signalling pathway were activated.

CONCLUSION

HG feeding leads to subacute rumen acidosis and a decreased milk fat content. The fatty acid profiles in the milk and plasma of dairy cows were changed by HG feeding. In muscle and adipose tissue, HG feeding increased TG concentration and up-regulated the expression of genes related to adipogenesis, while down-regulated the expression of genes related to lipid transport. These results complement our knowledge of the fatty acid composition of muscle and adipose tissue in dairy cows and expand our understanding of the mechanisms by which HG diets affect lipid metabolism in muscle and adipose tissue.

The efficacy and safety of cupping as complementary and alternative therapy for metabolic syndrome: A systematic review and meta-analysis

INTRODUCTION

This systematic review and meta-analysis aimed to assess the efficacy and safety of cupping therapy in patients with metabolic syndrome (MetS).

METHODS

This systematic review focused on patients with MetS and included randomized controlled trials (RCTs) that compared the effects of cupping therapy with control groups. A total of 12 electronic databases were searched from inception until February 03, 2023. The main outcome after the meta-analysis was waist circumference; the others included anthropometric variables, blood pressure, lipid profile, fasting blood glucose level, and high-sensitivity C-reactive protein level. The incidence of adverse events and the follow-up courses were also evaluated. Risk of bias (ROB) was evaluated using ROB 2.0 from the Cochrane Handbook.

RESULTS

This systematic review included five studies involving 489 patients. Some risks of bias were also identified. The meta-analysis revealed a statistically significance in waist circumference (MD = -6.07, 95% CI: -8.44 to -3.71, P < .001, I2 = 61%, τ2 = 3.4), body weight (MD = -2.46, 95% CI: -4.25 to -0.68, P = .007, I2 = 0%, τ2 = 0) and body mass index (MD = -1.26, 95% CI: -2.11 to -0.40, P = .004, I2 = 0%, τ2 = 0) between the cupping therapy and control groups. However, there were no significant results in total fat percentage and blood pressure values. Regarding biochemical markers, cupping significantly lowered the concentration of low-density lipoprotein cholesterol (MD = -3.98, 95% CI: -6.99 to -0.96, P = .010, I2 = 0%, τ2 = 0) but had no significant effect on total cholesterol, triglyceride, high-density lipoprotein cholesterol, fasting blood glucose, and high-sensitivity C-reactive protein. 3 RCTs reported no adverse events.

CONCLUSIONS

Despite some ROB and low to substantial heterogeneity of the included studies, cupping therapy can be considered a safe and effective complementary intervention for reducing waist circumference, body weight, body mass index, and low-density lipoprotein cholesterol in patients with MetS. In the future, well-designed, high-quality, rigorous methodology, and long-term RCTs in this population are required to assess the efficacy and safety of cupping therapy.

Protocol for in vivo and ex vivo assessment of hyperglycemia and islet function in diabetic mice

Mouse hyperglycemia model and islet function assessment are essential in diabetes research. Here, we provide a protocol to evaluate glucose homeostasis and islet functions in diabetic mice and isolated islets. We describe steps for establishing type 1 and 2 diabetes, glucose tolerance test, insulin tolerance test, glucose stimulated insulin secretion (GSIS) assay, and histological analysis for islet number and insulin expression in vivo. We then detail islet isolation, islet GSIS, β-cell proliferation, apoptosis, and programming assays ex vivo. For complete details on the use and execution of this protocol, please refer to Zhang et al. (2022).1.

Breast cancer and dietary fat quality indices in Iranian women: A case-control study

Background

The association between breast cancer (BC) and different indices of dietary fats has not been well-studied. Thus, this study aimed to investigate the association between BC and dietary fat quality (DFQ) indices in Iranian women.

Methods

This case-control study was conducted on 120 women with breast cancer and 240 healthy women in Tehran, Iran. Food Frequency Questionnaire and nutritionist IV software were used to assess the intake of dietary fats and to calculate the DFQ indices.

Results

The patients with BC had a higher total fat (TF) (P < 0.01) and a lower ratio of polyunsaturated fatty acids (PUFAs) omega-3 to PUFAs omega-6 (ω-3/ω-6) compared with the controls (P < 0.001). TF had a significant association with BC risk (OR: 1.16; 95% CI: 1.01-1.33, P < 0.001). No significant association was found between BC and PUFA/saturated fatty acid ratio or the ω-3/ω-6 ratio.

Conclusion

The patients with BC had a lower ω-3/ω-6 ratio and a higher total dietary fat intake than the healthy women. Total dietary fat intake was also directly associated with the risk of BC. Thus, low-fat diets may have beneficial effects for BC prevention. Further longitudinal studies are warranted.

High insulinemic potential of diet and lifestyle is associated with increased risk of chronic kidney disease incident in adults

BACKGROUND

The role of higher insulinemic effects of dietary pattern and lifestyle factors on the risk of chronic kidney disease (CKD) is not well-studied. In the current study, we aimed to investigate the relationship between the insulinemic potential of diet and lifestyle with the risk of CKD in adults.

METHODS

A total of 6044 individuals without CKD, aged>18 years, were recruited from among participants of the Tehran Lipid and Glucose Study (third and fourth surveys) and followed a mean of 6.03 years(follow-up rate:94.95%). The dietary intake data were collected using a food frequency questionnaire. The insulinemic potential of diet and lifestyle was determined based on four empirical indices, including the empirical dietary index for hyperinsulinemia (EDIH), the empirical dietary index for insulin resistance (EDIR), the empirical lifestyle index for hyperinsulinemia (ELIH), and the empirical lifestyle index for insulin resistance (ELIR).

RESULTS

Mean ± SD age of all study participants (54.3% women) was 37.8 ± 12.8 years. During the 6.03 years of follow-up (46,889.8 person-years), 1216(20.1%) new cases of CKD were identified. According to the multivariable-adjusted model, the risk of CKD incident is increased across quintiles of EDIR (OR = 1.29;95% CI: 1.06-1.57), ELIH (OR = 1.35; 95%CI: 1.10-1.67), and ELIR (OR = 1.24; 95%CI:1.02-1.51). However, no significant relationship was found between the EDIH score and the risk of CKD.

CONCLUSION

Results of the current study showed that dietary pattern with a high EDIR score and a lifestyle with higher ELIH and ELIR scores may be related to increasing the risk of CKD incident. However, no significant association was observed between EDIH score and CKD incident.

Associations between overall, healthful, and unhealthful low-fat dietary patterns and breast cancer risk in a Mediterranean cohort: The SUN project

OBJECTIVES

Dietary patterns may have a greater influence on human health than individual foods or nutrients, and they are also of substantial interest in the field of breast cancer prevention. Beyond the adequate balance of macronutrients, evidence indicates that the quality of macronutrient sources may play an important role in health outcomes. We sought to examine the relationship between healthful and unhealthful low-fat dietary patterns in relation to breast cancer.

METHODS

We used observational data from a Mediterranean cohort study (the Seguimiento Universidad de Navarra project). We prospectively followed 10 930 middle-aged women initially free of breast cancer during a median follow-up of 12.1 y. We calculated an overall, an unhealthful, and a healthful low-fat diet score, based on a previously validated 136-item food frequency questionnaire and grouped participants into tertiles. Incident breast cancer-overall and stratified by menopausal status-was the primary outcome. It was self-reported by participants and confirmed based on medical reports or consultation of the National Death Index. We used multivariable Cox regression models adjusted for potential confounders.

RESULTS

During 123 297 person-years of follow-up, 150 cases of incident breast cancer were confirmed. No significant associations were observed for overall or premenopausal breast cancer. For postmenopausal women, we observed a significant association for moderate adherence to the unhealthful low-fat dietary score and postmenopausal breast cancer (comparing tertile 2 to tertile 1; hazard ratio = 2.18; 95% confidence interval, 1.15-4.13).

CONCLUSIONS

In conclusion, no clear associations were observed, although more research is needed to address the association between an unhealthful dietary pattern and postmenopausal breast cancer risk.

Progression from prediabetes to type 2 diabetes mellitus induced by overnutrition

Prediabetes has developed into a global pandemic, its prevalence increasing year by year. Although lifestyle changes are advocated as the basis for prediabetes treatment, some patients fail to choose or adhere to appropriate interventions. The basis for selecting an appropriate intervention is determining the stage and cause of the disease. In this review, we aimed to examine the various types and disease processes of prediabetes caused by overnutrition, the present review supporting the hypothesis that overnutrition-induced hyperinsulinemia precedes insulin resistance (IR) and independently causes β-cell dysfunction. Tissue insulin resistance is the main feature of prediabetes with the crosstalk between tissues promoting the formation of systemic insulin resistance. Finally, both β-cell dysfunction induced by hyperinsulinemia or IR and reduced β-cell mass can lead to abnormal insulin secretion and contribute to development of type 2 diabetes mellitus (T2DM). Hence, overnutrition can cause multiple prediabetes phenotypes resulting in development of T2DM through different trajectories. Future diagnosis and treatment should therefore more carefully consider the disease phenotype and stage of development in patients with prediabetes to reduce the incidence of T2DM.

Dietary Plant Protein Intake Can Reduce Maternal Insulin Resistance during Pregnancy

Evidence suggests that the source of dietary protein may have an impact on insulin resistance, but no studies have explored it in pregnant populations. In this study, we combined a population study and an animal experiment to explore this effect. The population study was conducted with data from NHANES. Multiple linear regression was used to observe the association of protein intake with outcomes, including fasting glucose (GLU), insulin (INS), and HOMA-IR. In the animal experiment, 36 pregnant SD rats in three groups were orally administered 100% animal protein, 50% animal protein and 50% plant protein, or 100% plant protein, respectively. The intervention continued throughout the whole pregnancy. On day 19.5, maternal plasma was collected after overnight fasting, and metabolomics was performed using UPLC-MS. We found plant protein intake was negatively correlated with INS and HOMA-IR in the whole population. During the third trimester, a similar correlation was also observed. The animal experiment also presented the same result. In metabolomic analysis, changes in various metabolites and related pathways including FoxO and mTOR signaling pathways were observed. In conclusion, we found a negative association between dietary plant protein intake and maternal insulin resistance during pregnancy. Changes in some active substances and related metabolic pathways may play an important role.

The effects of olive oil consumption on blood lipids: a systematic review and dose-response meta-analysis of randomised controlled trials

We performed a systematic review and dose-response meta-analysis of randomised trials on the effects of olive oil consumption on blood lipids in adults. A systematic search was performed in PubMed, Scopus and Web of Science databases until May 2021. Randomised controlled trials (RCT) evaluating the effect of olive oil intake on serum total cholesterol (TC), TAG, LDL-cholesterol and HDL-cholesterol in adults were included. The mean difference (MD) and 95 % CI were calculated for each 10 g/d increment in olive oil intake using a random-effects model. A total of thirty-four RCT with 1730 participants were included. Each 10 g/d increase in olive oil consumption had minimal effects on blood lipids including TC (MD: 0·79 mg/dl; 95 % CI (-0·08, 1·66); I² = 57 %; n 31, GRADE = low certainty), LDL-cholesterol (MD: 0·04 mg/dl, 95 % CI (-1·01, 0·94); I² = 80 %; n 31, GRADE = very low certainty), HDL-cholesterol (MD: 0·22 mg/dl; 95 % CI (-0·01, 0·45); I² = 38 %; n 33, GRADE = low certainty) and TAG (MD: 0·39 mg/dl; 95 % CI (-0·33, 1·11); I² = 7 %; n 32, GRADE = low certainty). Levels of TC increased slightly with the increase in olive oil consumption up to 30 g/d (MD_{30 g/d}: 2·76 mg/dl, 95 % CI (0·01, 5·51)) and then appeared to plateau with a slight downward curve. A trivial non-linear dose-dependent increment was seen for HDL-cholesterol, with the greatest increment at 20 g/d (MD_{20 g/d}: 1·03 mg/dl, 95 % CI (-1·23, 3·29)). Based on existing evidence, olive oil consumption had trivial effects on levels of serum lipids in adults. More large-scale randomized trials are needed to present more reliable results.

Vitamin C intake potentially lowers total cholesterol to improve endothelial function in diabetic patients at increased risk of cardiovascular disease: A systematic review of randomized controlled trials

BACKGROUND

Vitamin C is one of the most consumed dietary compounds and contains abundant antioxidant properties that could be essential in improving metabolic function. Thus, the current systematic review analyzed evidence on the beneficial effects of vitamin C intake on cardiovascular disease (CVD)-related outcomes in patients with diabetes or metabolic syndrome.

METHODS

To identify relevant randomized control trials (RCTs), a systematic search was run using prominent search engines like PubMed and Google Scholar, from beginning up to March 2022. The modified Black and Downs checklist was used to assess the quality of evidence.

RESULTS

Findings summarized in the current review favor the beneficial effects of vitamin C intake on improving basic metabolic parameters and lowering total cholesterol levels to reduce CVD-risk in subjects with type 2 diabetes or related metabolic diseases. Moreover, vitamin C intake could also reduce the predominant markers of inflammation and oxidative stress like C-reactive protein, interleukin-6, and malondialdehyde. Importantly, these positive outcomes were consistent with improved endothelial function or increased blood flow in these subjects. Predominantly effective doses were 1,000 mg/daily for 4 weeks up to 12 months. The included RCTs presented with the high quality of evidence.

CONCLUSION

Clinical evidence on the beneficial effects of vitamin C intake or its impact on improving prominent markers of inflammation and oxidative stress in patients with diabetes is still limited. Thus, more RCTs are required to solidify these findings, which is essential to better manage diabetic patients at increased risk of developing CVD.

The Effect of Walnut Intake on Lipids: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Cardiovascular diseases (CVD) are the leading causes of death worldwide. Dyslipidemia is a cardiometabolic risk factor of CVD, yet it can be modifiable. Walnuts have been suggested as a dietary intervention to improve the lipid profile. Therefore, we reviewed the literature to assess the evidence linking walnut intake to the improvement of blood lipids, including total cholesterol (TC), low-density lipoprotein (LDL-C) cholesterol, high-density lipoprotein (HDL-C) cholesterol, and triglycerides (TG). PubMed and Embase databases were searched from 2010 up to March 2022. We limited our search to randomized controlled trials conducted on humans and published in English during the specified period. Cochrane's risk of bias tool for interventional studies was used. A random-effects model was used for the meta-analysis, and weighted mean differences were obtained (WMD) Thirteen trials from the U.S., Europe, and Asia were included. Walnut intake was associated with significant reductions in TC (WMD: -8.58 mg/dL), LDL-C (WMD: -5.68 mg/dL), and TG (WMD: -10.94 mg/dL). Walnut consumption was not associated with HDL-C. Subgroup analysis showed that overweight/obese and those with comorbidities had more lipid improvement. A longer trial duration did result in further improvements. However, our results may be prone to bias due to extraneous confounding factors. Additionally, levels of heterogeneity were considerable for some outcomes of interest. Results from this meta-analysis provide evidence for the health benefits of walnuts on blood lipids. Walnuts possibly reduce the risk of CVD; thus, they can be successfully added to a dietary pattern to enhance health benefits.

Hypercaloric Diet Promotes Metabolic Disorders and Impaired Kidney Function

Poor dietary habits such as overconsumption of hypercaloric diets characterized by a high content of fructose and fat are related to metabolic abnormalities development such as obesity, diabetes, and dyslipidemia. Accumulating evidence supports the hypothesis that if energy intake gradually exceeds the body's ability to store fat in adipose tissue, the prolonged metabolic imbalance of circulating lipids from endogenous and exogenous sources leads to ectopic fat distribution in the peripheral organs, especially in the heart, liver, and kidney. The kidney is easily affected by dyslipidemia, which induces lipid accumulation and reflects an imbalance between fatty acid supply and fatty acid utilization. This derives from tissue lipotoxicity, oxidative stress, fibrosis, and inflammation, resulting in structural and functional changes that lead to glomerular and tubule-interstitial damage. Some authors indicate that a lipid-lowering pharmacological approach combined with a substantial lifestyle change should be considered to treat chronic kidney disease (CKD). Also, the new therapeutic target identification and the development of new drugs targeting metabolic pathways involved with kidney lipotoxicity could constitute an additional alternative to combat the complex mechanisms involved in impaired kidney function. In this review article, we first provide the pathophysiological evidence regarding the impact of hypercaloric diets, such as high-fat diets and high-fructose diets, on the development of metabolic disorders associated with impaired renal function and the molecular mechanisms underlying tissue lipid deposition. In addition, we present the current progress regarding translational strategies to prevent and/or treat kidney injury related to the consumption of hypercaloric diets.

Oat β-glucan and L-arabinose synergistically ameliorate glucose uptake in insulin-resistant HepG2 cells and exert anti-diabetic activity via activation of the PI3K/AKT pathway in db/db mice

Oat β-glucan (OBG) and L-arabinose (LA) have exhibited positive effects on diabetes and its complications. However, it is unclear whether OBG and LA have a synergistic effect. We investigated the effect of variable compositions (OBG : LA = 1 : 1, 1 : 2, 1 : 4,1 : 6, 1 : 8, 1 : 10, 2 : 1, 4 : 1, 6 : 1, 8 : 1, 10 : 1) on glucose uptake in IR-HepG2 cells induced by dexamethasone (DEX) to find out the optimal composition showing synergistic effects. Furthermore, this study evaluated the anti-diabetic activity of the optimal composition in db/db mice. In vitro, the OBG : LA = 1 : 1 group showed the strongest synergistic effects among the varied compositions, outperforming OBG and LA alone. In vivo, there were more beneficial effects in the OBG : LA = 1 : 1 group compared with the OBG and LA single-dosing groups. OBG : LA = 1 : 1 supplementation markedly decreased the levels of fasting blood glucose (FBG) and insulin (INS) in serum, improved glucose tolerance and insulin sensitivity, lowered blood lipid levels, and reduced liver lipid accumulation. Moreover, the western blot results indicated that the OBG : LA = 1 : 1 group up-regulated the protein expression of glucose transporter-4 (GLUT4), phosphatidylinositol 3-kinase (PI3K), and phospho-protein kinase B (p-AKT), while down-regulating the protein expression of phospho-phosphorylated insulin receptor substrate-1 (p-IRS1) to enhance insulin transduction in liver tissues. These findings suggest that OBG : LA = 1 : 1 synergistically ameliorated glucose metabolism disorders and alleviated insulin resistance by promoting the PI3K/AKT pathway in the liver.

High fat diets induce early changes in gut microbiota that may serve as markers of ulterior altered physiological and biochemical parameters related to metabolic syndrome. Effect of virgin olive oil in comparison to butter

Butter and virgin olive oil (EVOO) are two fats differing in their degree of saturation and insaponifiable fraction. EVOO, enriched in polyphenols and other minority components, exerts a distinct effect on health. Using next generation sequencing, we have studied early and long-term effects of both types of fats on the intestinal microbiota of mice, finding significant differences between the two diets in the percentage of certain bacterial taxa, correlating with hormonal, physiological and metabolic parameters in the host. These correlations are not only concomitant, but most noticeably some of the changes detected in the microbial percentages at six weeks are correlating with changes in physiological values detected later, at twelve weeks. Desulfovibrionaceae/Desulfovibrio/D. sulfuricans stand out by presenting at six weeks a statistically significant higher percentage in the butter-fed mice with respect to the EVOO group, correlating with systolic blood pressure, food intake, water intake and insulin at twelve weeks. This not only suggests an early implication in the probability of developing altered physiological and biochemical responses later on in the host lifespan, but also opens the possibility of using this genus as a marker in the risk of suffering different pathologies in the future.

Insulin resistance and cardiometabolic indexes: comparison of concordance in working-age subjects with overweight and obesity

PURPOSE

The aim of the study was to evaluate indexes of insulin resistance and cardiometabolic risk in a large population of workers with overweight or obesity, in order to identify a possible efficient, cheap and simple strategy to apply in workers' health surveillance.

METHODS

The evaluation of IR and cardiometabolic risk indexes (HOMA, QUICKI, Ty/HDLC, TyG, insuTAG, Castelli risk indexes 1 and 2, non-HDLC, TRL-C, AIP, and VAI) was performed in a population of 1195 working-age subjects with overweight or obesity (322 males, mean age 49 ± 11 years).

RESULTS

The prevalence of IR and cardiometabolic risk was higher among males for all indexes. Aging, waist circumference, BMI, blood pressure, glucose, CRP, fibrinogen and uric acid were correlated more frequently with IR/cardiometabolic indexes in women, homocysteine in men. The percentage of the workers identified as insulin resistant (IR+) or at higher cardiometabolic risk greatly vary according to the different index used.

CONCLUSION

With a small group of biomarkers and anthropometric measures (fasting glucose and insulin, lipid profile, BMI and waist circumference) is possible to calculate a number of IR/cardiometabolic indexes, which, likely reflecting different pathophysiological aspects also related to gender, might help in a personalized evaluation of IR and cardiometabolic risk. Graphical abstract.

Cinnamaldehyde Mitigates Atherosclerosis Induced by High-Fat Diet via Modulation of Hyperlipidemia, Oxidative Stress, and Inflammation

Atherosclerosis is a disease in which plaque builds up inside arteries. Cinnamaldehyde (Ci) has many biological properties that include anti-inflammatory and antioxidant activities. Thus, this study was designed to explore the protective effect of Ci against atherosclerosis induced by a high-fat diet (HFD) in Wistar rats. Atherosclerosis was induced by an oral administration of an HFD for 10 weeks. Atherosclerosis-induced rats were supplemented with Ci at a dose of 20 mg/kg bw dissolved in 0.5% dimethyl sulfoxide (DMSO), daily by oral gavage for the same period. Rats were divided into three groups of 10 rats each fed with (a) ND, (b) HFD, and (c) HFD+Ci, daily for 10 weeks. Treatment of rats with Ci significantly reduced the elevated levels of serum total cholesterol (T.Ch), triglycerides (TG), low-density lipoprotein-cholesterol (LDL-Ch), very low-density lipoprotein-cholesterol (VLDL-Ch), and free fatty acids (FFAs) and significantly increased the lowered levels of high-density lipoprotein-cholesterol (HDL-Ch) level. Ci ameliorated the increased cardiovascular risk indices 1 and 2 and the decreased antiatherogenic index. Moreover, Ci reduced the elevated serum creatine kinase (CK), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST) activities. Ci also improved the heart antioxidant activities by decreasing malondialdehyde (MDA) and increasing glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and glutathione peroxidase (Gpx) activities. Furthermore, the supplementation with Ci downregulated the mRNA expression levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-17 (IL-17), and tumor necrosis factor-α (TNF-α). Thus, Ci successfully elicited a therapeutic impact against atherosclerosis induced by HFD via its hypolipidemic, antioxidant, and anti-inflammatory actions.

Dietary Assessment Tools and Metabolic Syndrome: Is It Time to Change the Focus?

Metabolic syndrome (MS) is associated with a range of chronic diseases, for which lifestyle interventions are considered the cornerstone of treatment. Dietary interventions have primarily focused on weight reduction, usually via energy restricted diets. While this strategy can improve insulin sensitivity and other health markers, weight loss alone is not always effective in addressing all risk factors associated with MS. Previous studies have identified diet quality as a key factor in reducing the risk of MS independent of weight loss. Additionally, supporting evidence for the use of novel strategies such as carbohydrate restriction and modifying the frequency and timing of meals is growing. It is well established that dietary assessment tools capable of identifying dietary patterns known to increase the risk of MS are essential for the development of personalised, targeted diet and lifestyle advice. The American Heart Association (AHA) recently evaluated the latest in a variety of assessment tools, recommending three that demonstrate the highest evidence-based and clinical relevance. However, such tools may not assess and thus identify all dietary and eating patterns associated with MS development and treatment, especially those which are new and emerging. This paper offers a review of current dietary assessment tools recommended for use by the AHA to assess dietary and eating patterns associated with MS development. We discuss how these recommendations align with recent and novel evidence on the benefits of restricting ultra-processed food and refined carbohydrates and modifying timing and frequency of meals. Finally, we provide recommendations for future redevelopment of these tools to be deployed in health care settings.

Pharmacological Targeting of Mitochondrial Fission and Fusion Alleviates Cognitive Impairment and Brain Pathologies in Pre-diabetic Rats

It has recently been accepted that long-term high-fat diet (HFD) intake is a significant possible cause for prediabetes and cognitive and brain dysfunction through the disruption of brain mitochondrial function and dynamic balance. Although modulation of mitochondrial dynamics by inhibiting fission and promoting fusion has been shown to reduce the morbidity and mortality associated with a variety of chronic diseases, the impact of either pharmacological inhibition of mitochondrial fission (Mdivi-1) or stimulation of fusion (M1) on brain function in HFD-induced prediabetic models has never been studied. Thirty-two male Wistar rats were separated into 2 groups and fed either a normal diet (ND, n = 8) or HFD (n = 24) for 14 weeks. At week 12, HFD-fed rats were divided into 3 subgroups (n = 8/subgroup) and given an intraperitoneal injection of either saline, Mdivi-1 (1.2 mg/kg/day), or M1 (2 mg/kg/day) for 2 weeks. Cognitive function and metabolic parameters were determined toward the end of the protocol. The rats then were euthanized, and the brain was immediately removed in order to evaluate brain mitochondrial function and mitochondrial dynamics. HFD-fed rats experienced prediabetes, evidenced by elevated plasma insulin and the HOMA index, impaired mitochondrial function in the brain, altered dynamic regulation, and cognitive impairment were also found. Mdivi-1 and M1 treatment exerted neuroprotection to a similar extent by improving metabolic parameters, balancing mitochondrial dynamics, and reducing mitochondrial dysfunction, resulting in a gradual increase in cognitive function. Therefore, pharmacological targeting of mitochondrial fission and fusion protected the brain against chronic HFD-induced prediabetes.

Perinatal Combinational Exposure to Bisphenol A and a High-Fat Diet Contributes to Transgenerational Dysregulation of Cardiovascular and Metabolic Systems in Mice

Both bisphenol A (BPA) and high-fat diet (HFD) exert unfavorable effects on animals and humans; moreover, they could affect the health of their offspring. BPA and HFD often coexist in modern lifestyles; however, the long-term effects of simultaneous exposure of mothers to BPA and HFD during the perinatal period on the cardiovascular and metabolic systems of the offspring remain unclear. This study aimed to examine the effect of simultaneous exposure of mothers to BPA and HFD on the risk of metabolic and cardiovascular abnormalities in offspring. Institute of Cancer Research female mice (F0) were exposed to BPA and fed with HFD before and during gestation until the end of lactation. F0 mice were mated with untreated males to produce the first generation (F1); subsequently, adult F1 males/females were mated with normal females/males to produce the second generation (F2). Combined maternal exposure to BPA and HFD caused myocardial hypertrophy and aortic tunica media thickening as well as increased the cross-sectional area of cardiomyocytes and blood pressure in the matrilineal F2 generation. These cardiovascular changes might be associated with reduced endothelial nitric oxide synthase (eNOS) levels. The patrilineal female F2 was more likely to be obese than the patrilineal male F2. Re-feeding with a HFD showed a more significant weight gain and reduced energy expenditure. However, the aforementioned effects were not observed with exposure to HFD or BPA alone during the perinatal period. Our findings suggest that perinatal combinational exposure to BPA and HFD could cause metabolic and cardiovascular disorders in the offspring, Further, our findings demonstrate that the synergistic effects of HFD and BPA could be transmitted to future generations in a sex-dependent manner.

A 4-week high-AGE diet does not impair glucose metabolism and vascular function in obese individuals

BACKGROUND

Accumulation of advanced glycation endproducts (AGEs) may contribute to the pathophysiology of type 2 diabetes and its vascular complications. AGEs are widely present in food, but whether restricting AGE intake improves risk factors for type 2 diabetes and vascular dysfunction is controversial.

METHODS

Abdominally obese but otherwise healthy individuals were randomly assigned to a specifically designed 4-week diet low or high in AGEs in a double-blind, parallel design. Insulin sensitivity, secretion, and clearance were assessed by a combined hyperinsulinemic-euglycemic and hyperglycemic clamp. Micro- and macrovascular function, inflammation, and lipid profiles were assessed by state-of-the-art in vivo measurements and biomarkers. Specific urinary and plasma AGEs N^ε-(carboxymethyl)lysine (CML), N^ε-(1-carboxyethyl)lysine (CEL), and N^δ-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1) were assessed by mass spectrometry.

RESULTS

In 73 individuals (22 males, mean ± SD age and BMI 52 ± 14 years, 30.6 ± 4.0 kg/m²), intake of CML, CEL, and MG-H1 differed 2.7-, 5.3-, and 3.7-fold between the low- and high-AGE diets, leading to corresponding changes of these AGEs in urine and plasma. Despite this, there was no difference in insulin sensitivity, secretion, or clearance; micro- and macrovascular function; overall inflammation; or lipid profile between the low and high dietary AGE groups (for all treatment effects, P > 0.05).

CONCLUSION

This comprehensive RCT demonstrates very limited biological consequences of a 4-week diet low or high in AGEs in abdominally obese individuals.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT03866343; trialregister.nl, NTR7594.

FUNDING

Diabetesfonds and ZonMw.

Dietary iron intake and the risk of type 2 diabetes: a systematic review and dose-response meta-analysis of prospective cohort studies

PURPOSE

We aimed to assess the long-term association of total, heme, non-heme, and supplemental iron intake and risk of type 2 diabetes (T2D).

METHODS

PubMed, Scopus, and Web of Science were searched to October 2021. Two researchers extracted data in duplicate and rated the certainty in the estimates using the GRADE approach. Random-effects models were applied to estimate the relative risks (RRs) and 95% CIs. Dose-response associations were modeled by a one-stage weighted mixed-effects meta-analysis.

RESULTS

Eleven prospective cohort studies 323,788 participants and 28,837 incident cases of T2D were included. High versus low category meta-analysis indicated that higher heme iron intake was associated with a 20% higher risk of T2D (95% CI 1.07, 1.35; I² = 77%, n = 11; GRADE = moderate). Dose-response analysis indicated a positive monotonic association, wherein each 1 mg/day increment in heme iron intake was related to a 16% higher risk (95% CI 1.03, 1.30). No significant relationship was detected between dietary intakes of total, non-heme, and supplemental iron and risk of T2D (GRADE = very low).

CONCLUSIONS

In summary, higher heme iron intake was associated with a higher risk of T2D. Our results are in line with existing evidence indicating that adopting a Western-style dietary pattern, rich in dietary sources of heme iron, was associated with a higher risk of T2D.

REGISTRY AND REGISTRY NUMBER

The protocol of this systematic review was registered at PROSPERO (registration number: CRD42021226835).

A meal enriched in saturated fat acutely impairs cognitive performance in obese men

BACKGROUND

Diets chronically high in saturated fat (SFA) associate with obesity and insulin resistance (IR), which in turn associate with cognitive decline and dementia. However, understanding how acute SFA consumption influences cognition is less clear despite short-term SFA-enriched diets inducing whole-body IR. We examined how consuming meals enriched with SFA or monounsaturated fat (MUFA) acutely influence cognitive function in lean and obese men. We hypothesized that greater diet-induced IR following a SFA-enriched meal would associate with decreased cognitive performance.

METHODS

Twelve lean and 12 obese males ingested meals containing no fat (CTL), enriched with SFA, or enriched with MUFA in a single-blind, randomized fashion. Cognitive testing and blood sampling were performed pre- and 2 h post-meal. Oral glucose tolerance (OGTT) and body composition were also assessed.

RESULTS

At baseline, fasting glucose, insulin, HOMA-IR, triglyceride, IL-6, and 2-hr glucose during an OGTT were higher in obese men (p < 0.001), while executive function (Stroop Test and Trail Making Test B-A) and working memory (Digit Span Test) were lower in obese men (p < 0.05). In response to the CTL and MUFA-enriched, no differences in cognitive measures were observed in lean or obese subjects. Following a SFA-enriched meal, obese subjects scored worse during cognitive testing (Stroop Test, Trail Making Test B-A, and Digit Span Test) compared to pre-meal scores (p < 0.05). These impairments in cognitive testing scores following the SFA-enriched meal associated with increased HOMA-IR (p < 0.01) and decreased plasma IL-6 (p < 0.05). No changes in cognitive function were observed in lean subjects following a SFA-enriched meal.

CONCLUSIONS

These data demonstrate that cognitive performance of obese men acutely worsens following a high-SFA meal. Reductions in cognitive performance associated with increased IR, suggesting that diet-induced IR may acutely decrease cognitive function.

SNAP25 mutation disrupts metabolic homeostasis, steroid hormone production and central neurobehavior

OBJECTIVE

SNAP-25 is one of the key proteins involved in formation of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complexes that are at the core of hormonal secretion and synaptic transmission. Altered expression or function of SNAP-25 can contribute to the development of neuropsychiatric and metabolic disease. A dominant negative (DN) I67T missense mutation in the b-isoform of SNAP-25 (DN-SNAP25mut) mice leads to abnormal interactions within the SNARE complex and impaired exocytotic vesicle recycling, yet the significance of this mutation to any association between the central nervous system and metabolic homeostasis is unknown.

METHODS

Here we explored aspects of metabolism, steroid hormone production and neurobehavior of DN-SNAP25mut mice.

RESULTS

DN-SNAP25mut mice displayed enhanced insulin function through increased Akt phosphorylation, alongside increased adrenal and gonadal hormone production. In addition, increased anxiety behavior and beigeing of white adipose tissue with increased energy expenditure were observed in mutants.

CONCLUSIONS

Our results show that SNAP25 plays an important role in bridging central neurological systems with peripheral metabolic homeostasis, and provide potential insights between metabolic disease and neuropsychiatric disorders in humans.

The Different Insulin-Sensitising and Anti-Inflammatory Effects of Palmitoleic Acid and Oleic Acid in a Prediabetes Model

INTRODUCTION

Monounsaturated fatty acids (MUFA) are understood to have therapeutic and preventive effects on chronic complications associated with type 2 diabetes mellitus (T2DM); however, there are differences between individual MUFAs. Although the effects of palmitoleic acid (POA) are still debated, POA can regulate glucose homeostasis, lipid metabolism, and cytokine production, thus improving metabolic disorders. In this study, we investigated and compared the metabolic effects of POA and oleic acid (OA) supplementation on glucose and lipid metabolism, insulin sensitivity, and inflammation in a prediabetic model, the hereditary hypertriglyceridemic rat (HHTg). HHTg rats exhibiting genetically determined hypertriglyceridemia, insulin resistance, and impaired glucose tolerance were fed a standard diet. POA and OA were each administered intragastrically at a dose of 100 mg/kg b.wt. for four weeks.

RESULTS

Supplementation with both MUFAs significantly elevated insulin and glucagon levels, but only POA decreased nonfasting glucose. POA-treated rats showed elevated circulating NEFA associated with increased lipolysis, lipoprotein lipase gene expression, and fatty acid reesterification in visceral adipose tissue (VAT). The mechanism of improved insulin sensitivity of peripheral tissues (measured as insulin-stimulated lipogenesis and glycogenesis) in POA-treated HHTg rats could contribute increased circulating adiponectin and omentin levels together with elevated FADS1 gene expression in VAT. POA-supplemented rats exhibited markedly decreased proinflammatory cytokine production by VAT, which can alleviate chronic inflammation. OA-supplemented rats exhibited decreased arachidonic acid (AA) profiles and decreased proinflammatory AA-derived metabolites (20-HETE) in membrane phospholipids of peripheral tissues. Slightly increased FADS1 gene expression after OA along with increased adiponectin production by VAT was reflected in slightly ameliorated adipose tissue insulin sensitivity (increased insulin-stimulated lipogenesis).

CONCLUSIONS

Our results show that POA served as a lipokine, ameliorating insulin sensitivity in peripheral tissue and markedly modulating the metabolic activity of VAT including cytokine secretion. OA had a beneficial effect on lipid metabolism and improved inflammation by modulating AA metabolism.

Associations of Dietary Inflammatory Index With Prediabetes and Insulin Resistance

BACKGROUND AND AIMS

Previous studies suggested that dietary inflammatory index (DII) was associated with a variety of adverse health conditions. However, less is known about the role of DII in prediabetes and insulin resistance (IR). Therefore, this study aimed to investigate whether DII is associated with prediabetes and IR in American adults.

METHOD AND RESULTS

DII scores were calculated using the average of two 24-hour dietary recalls. Linear regression models were performed to evaluate the associations of DII with markers of Type 2 diabetes (T2D) risk, and the associations of DII with prediabetes and IR were estimated using logistic regression model. The diet of the participants showed an anti-inflammatory potential, with a mean DII score of -0.14 (range: -5.83 to +5.32). After controlling for multiple potential confounders, DII scores were positively associated with fasting plasma glucose (FPG) (β: 0.009; 95%CI: 0.005 to 0.012), fasting serum insulin (FSI) (β: 0.083; 95%CI: 0.067 to 0.099) and homeostatic model assessment of insulin resistance (HOMA-IR) (β: 0.092; 95%CI: 0.075 to 0.109). Participants in the highest tertile of DII score have increased odds of prediabetes (OR: 1.40; 95%CI: 1.17 to 1.69; P for trend <0.001) and IR (OR: 1.79; 95%CI: 1.49 to 2.14; P for trend <0.001) compared with those in the first tertile of DII score.

CONCLUSIONS

This study indicates that DII was positively associated with FPG, FSI, and HOMA-IR, and a more pro-inflammatory diet was related to increased odds of insulin resistant and prediabetes.

Odd chain fatty acid metabolism in mice after a high fat diet

Epidemiological studies show that higher circulating levels of odd chain saturated fatty acids (FA: C15:0 and C17:0) are associated with lower risk of metabolic disease. These odd chain saturated fatty acids (OCSFA) are produced by α-oxidation in peroxisomes, de novo lipogenesis, from the diet and by gut microbiota. Although present at low concentrations, they are of interest as potential targets to reduce metabolic disease risk. To determine whether OCSFA are affected by obesogenic diets, we have investigated whether high dietary fat intake affects the frequency of OCSFA-producing gut microbiota, liver lipid metabolism genes and circulating OCSFA. FA concentrations were determined in liver and serum from pathogen-free SPF C57BL/6 J mice fed either standard chow or a high fat diet (HFD; 60% calories as fat) for four and twelve weeks. Post-mortem mouse livers were analysed histologically for fat deposition by gas chromatography-mass spectrometry for FA composition and by qPCR for the lipid metabolic genes fatty acid desaturase 2 (FADS2), stearoyl CoA desaturase 1 (SCD1), elongation of long-chain fatty acids family member 6 (ELOVL6) and 2-hydroxyacyl-CoA lyase 1 (HACL). Gut microbiota in faecal pellets from the ileum were analysed by 16S RNA sequencing. A significant depletion of serum and liver C15:0 (>50%; P < 0.05) and liver C17:0 (>35%; P < 0.05) was observed in HFD-fed SPF mice in parallel with hepatic fat accumulation after four weeks. In addition, liver gene expression (HACL1, ELOVL6, SCD1 and FADS2) was lower (>50%; P < 0.05) and the relative abundance of beneficial C3:0-producing gut bacteria such as Akkermansia, Lactobacillus, Bifidobacterium was lower after HFD in SPF mice. In summary, high dietary fat intake reduces serum and liver OCSFA, OCSFA-producing gut microbiota and is associated with impaired liver lipid metabolism. Further studies are required to identify whether there is any beneficial effect of OCSFA and C3:0-producing gut bacteria to counter metabolic disease.

The association between meal specific low carbohydrate diet score and cardiometabolic risk factors: A cross-sectional study of Iranian adults

BACKGROUND AND AIM

Since evidence regarding low-CHO diet and cardiometabolic risk factors is controversial, this study aimed to assess the relation between low-CHO diet score and metabolic syndrome (MetS) and cardiometabolic risk factors among a group of Iranian adults.

METHODS

This cross-sectional study was conducted with 840 subjects with the age range of 20-65 years. Dietary intakes were assessed by completing three 24-hour recalls. Total, animal- and vegetable-based low-CHO diet score were calculated. We used logistic regression with different models to determine whether there were relationships between low-CHO diet score and MetS and MetS components.

RESULTS

We found that there was no significant association between low-CHO diet, animal-based and vegetable-based low-CHO diet scores and risk of MetS in three meals. Except for the animal-based low-CHO diet score, which was significantly associated with general obesity at lunch meal (OR: 1.17, 95% CI: 0.76-1.82, P = .03). There were a significant association between low-CHO diet and high-density lipoprotein cholesterol (HDL-C) levels in lunch meal (OR: 1.50, 95% CI: 1.06-2.14, P = .03). Vegetable-based low-CHO diet score was associated with a lower risk of elevated TG in lunch meal in the fully adjusted model (OR: 0.59, 95% CI: 0.39-0.90, P = .04).

CONCLUSION

Diets with lower amounts of carbohydrate and higher contents of fat and protein were not significantly associated with the risk for MetS in Iranian adults. Only animal-based low-CHO diet score was significantly associated with general obesity at lunch meal.

Egg and saturated fat containing breakfasts have no acute effect on acute glycemic control in healthy adults: a randomized partial crossover trial

BACKGROUND/OBJECTIVES

High egg consumption is associated with poor glycemic control. Considering the widespread consumption of eggs, it is crucial to determine causality in this association. We tested if egg consumption acutely alters glucose disposal in the absence or presence of saturated fat, which is frequently consumed with eggs.

SUBJECTS/METHODS

In a randomized partial crossover clinical trial, 48 subjects (consuming ≥ 1 egg/week) received two of four isocaloric, macronutrient-matched breakfasts. The groups were defined based on the main ingredient of the breakfasts offered: eggs (EB); saturated fat (SB); eggs and saturated fat (ES); and control, which included a cereal based breakfast (CB). The breakfasts were offered in two testing sessions spaced seven days apart. Six blood samples (pre breakfast (fasting); 30, 60, 90, 120, and 180 minutes post breakfast) were collected to measure glucose and insulin levels. Area under the curves (AUC) were analyzed controlling for the baseline concentrations using mixed-effects models accounting for within-subject dependencies to compare these across breakfast assignments.

RESULTS

Forty-eight patients (46% males, age 25.8 ± 7.7 years, BMI 25.7 ± 4.6 kg/m²) were included. Neither EB, SB nor ES was associated with a significant difference in AUC of glucose or insulin compared to CB (p > 0.1).

CONCLUSIONS

Acutely, consumption of egg breakfast with or without accompanying saturated fat does not adversely affect glucose disposal in healthy adults. While this is reassuring for continued egg consumption, a long-term evaluation of egg intake with or without saturated fat would be the next step.