-
1.
Effects of galactooligosaccharides on maternal gut microbiota, glucose metabolism, lipid metabolism and inflammation in pregnancy: A randomized controlled pilot study.
Wan, J, An, L, Ren, Z, Wang, S, Yang, H, Ma, J
Frontiers in endocrinology. 2023;14:1034266
-
-
-
Free full text
Plain language summary
During pregnancy, a disordered gut microbiome and abnormal glucose metabolism may be possible mechanisms for pregnancy complications such as gestational diabetes mellitus (GDM). Different from probiotics, galactooligosaccharides (GOS) is a prebiotic that is not digested and absorbed by the host, but can selectively promote the metabolism and proliferation of beneficial bacteria in the body, particularly Lactobacillus and Bifidobacterium. The aim of this study was to evaluate the feasibility, acceptability, and safety of prebiotic intervention in healthy pregnant women, and conduct a preliminary exploration of the possible benefits for pregnant women. This study was a prospective double-blinded randomised clinical trial involving pregnant women. Participants were randomly assigned to the control group and the intervention group at a 1:1 ratio. Results showed that GOS intervention had no significant effect on reducing the incidence of GDM and improving glucose and lipid metabolism. Furthermore, there was no significant difference in glucose and lipid metabolism levels between GOS group and placebo group. Authors conclude that GOS can be considered as a dietary supplement during pregnancy. However, further clinical studies are needed to strengthen the findings of this study.
Abstract
BACKGROUND Gut microbiota of pregnant women change with the gestational week. On the one hand, they participate in the metabolic adaptation of pregnant women. On the other hand, the abnormal composition of gut microbiota of pregnant women is more likely to suffer from gestational diabetes mellitus (GDM). Therefore, gut microbiota targeted treatment through dietary supplements is particularly important for prevention or treatment. Prebiotic supplements containing galactooligosaccharides (GOS) may be an intervention method, but the effect is still unclear. OBJECTIVE This study aims to evaluate the feasibility and acceptability of prebiotic intervention in healthy pregnant women during pregnancy, and to explore the possible effects of intervention on pregnant women and the influence on gut microbiota as preliminaries. METHODS After recruitment in first trimester, 52 pregnant women were randomly assigned to receive GOS intervention or placebo containing fructooligosaccharides. 16S rRNA sequencing technology was used to detect the composition, diversity and differential flora of gut microbiota. Lipid metabolism, glucose metabolism and inflammatory factors during pregnancy were also analyzed. RESULTS The adverse symptoms of GOS intervention are mild and relatively safe. For pregnant women, there was no significant difference in the GDM incidence rates and gestational weight gain (GWG) in the GOS group compared with placebo (P > 0.05). Compared with the placebo group, the levels of FPG, TG, TC, HDL-C LDL-C, and IL-6 had no significant difference in GOS group (P > 0.05). For newborns, there was no significant difference between GOS group and placebo group in the following variables including gestational week, birth weight, birth length, head circumference, chest circumference, sex, and delivery mode (P > 0.05). And compared with the placebo group, the GOS group had a higher abundance of Paraprevotella and Dorea, but lower abundance of LachnospiraceaeUCG_001. CONCLUSIONS GOS prebiotics appear to be safe and acceptable for the enrolled pregnancies. Although GOS intervention did not show the robust benefits on glucose and lipid metabolism. However, the intervention had a certain impact on the compostion of gut microbiota. GOS can be considered as a dietary supplement during pregnancy, and further clinical studies are needed to explore this in the future.
-
2.
Effects of intermittent very-low calorie diet on glycemic control and cardiovascular risk factors in obese patients with type 2 diabetes mellitus: A randomized controlled trial.
Umphonsathien, M, Rattanasian, P, Lokattachariya, S, Suansawang, W, Boonyasuppayakorn, K, Khovidhunkit, W
Journal of diabetes investigation. 2022;13(1):156-166
-
-
-
Free full text
Plain language summary
Various studies have shown that intermittent low-calorie diets are effective in reducing weight and improving glycaemic control. In this randomized controlled trial, two intermittent very-low calorie diets (2 days per week and 4 days per week) were evaluated against a control group with respect to achieving diabetes remission, improving glycemic control, metabolic parameters, and quality of life in Type 2 diabetic patients. There was a significant reduction in HbA1c and insulin resistance in the 2 days/week and 4 days/week intermittent very-low calorie groups at week 20. Both the intervention groups achieved diabetes remission with 29% of participants not requiring glucose-lowering medications at week 20. Both intervention groups also showed a significant reduction in serum triglycerides, body weight, body mass index, and fat mass. Aspartate transaminase and alanine aminotransferase levels, as well as blood pressure, decreased significantly with a 4 day/week intermittent low-calorie diet. Both intervention groups experienced improved quality of life at week 10 and the interventions were generally well tolerated. To generalise the results, longer-term, robust studies are required. These results can help healthcare providers understand the clinical relevance of intermittent very-low calorie diets in managing Type 2 diabetes and obesity.
Abstract
AIMS/INTRODUCTION Very few studies assess the effectiveness of different protocols of intermittent very-low calorie diet (VLCD) in patients with diabetes. This study was designed to compare the effects of 2 days/week and 4 days/week of intermittent VLCD on glycemic control, diabetes remission, metabolic parameters and quality of life in patients with type 2 diabetes and obesity. MATERIALS AND METHODS Participants with obesity and type 2 diabetes were recruited and randomly assigned to three groups, consisting of control, 2 days/week and 4 days/week of intermittent VLCD. In the intermittent VLCD groups, participants received a 600-kcal diet per day on restricted days and ad libitum food consumption on non-restricted days. Glycemic control, rate of diabetes remission, metabolic parameters and quality of life were evaluated at baseline, weeks 2, 10 and 20. RESULTS A total of 40 participants were enrolled. The mean body mass index was 30.1 ± 5.9 kg/m2 , and the mean glycated hemoglobin was 7.4 ± 1.2%. At week 20, there was an improvement in glycemic control in both intermittent VLCD groups with significant decreases in glycated hemoglobin levels and insulin resistance index throughout the study periods. Diabetes remission without the need for medications was equally found in 29% of participants in both intermittent VLCD groups. Serum triglyceride, bodyweight, body mass index and fat mass were also significantly decreased in both VLCD groups. No serious adverse events were encountered. CONCLUSION Intermittent VLCD was highly effective in achieving optimal glycemic control. The effects of 2 days/week and 4 days/week of intermittent VLCD on diabetes remission were relatively similar.
-
3.
Nigella sativa supplementation improves cardiometabolic indicators in population with prediabetes and type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials.
Saadati, S, Naseri, K, Asbaghi, O, Abhari, K, Zhang, P, Li, HB, Gan, RY
Frontiers in nutrition. 2022;9:977756
-
-
-
Free full text
Plain language summary
Chronic, non-infectious diseases contribute to nearly three-quarters of deaths worldwide. Type 2 diabetes mellitus (T2DM) together with cardiovascular disease, are the two most common conditions in this category. Insulin resistance, obesity, elevated blood fats, and high blood pressure are typical hallmarks of T2DM and its development and are also significant risk factors for diabetes-related cardiovascular events. The prolonged nature of T2DM and the complications that can go alongside make the condition one of the most costly diseases for healthcare systems hence finding cost-effective therapeutic strategies should be of high importance. Many functional plants and their bioactive components have shown to exert anti-diabetic effects, including Nigella sativa, commonly known as black cumin. Previous studies also reported promising benefits of Nigella on cardiometabolic health. How these effects manifest in individuals with T2DM and those who are prediabetic was analysed in this systematic review and meta-analysis. The review included 11 randomised controlled trials with a total of 666 subjects. The review focused on cardiometabolic measures such as body measurements, blood sugar control, insulin resistance and secretion, blood fats, and markers of inflammation and oxidative stress. Nigella supplementation appeared to have favourable effects on blood sugar control overall but with no changes in the outcomes of oral glucose tolerance tests. Furthermore, Nigella appeared to positively influence on various blood fats, and markers of inflammation and oxidative stress. There were no changes to fasting insulin, insulin resistance, triglyceride, high-density lipoprotein (HDL)-Cholesterol and body mass index (BMI) when compared to the control group. Yet, in a sub-analysis Nigella supplementation enhanced serum levels of 'good' HDL-Cholesterol in a particular group. An improvement in insulin resistance and a decrease in BMI were seen in supplementation trials lasting over 8-weeks with doses of over 1 g/day of Nigella. The authors concluded that Nigella has the potential to improve cardiometabolic parameters by favourably influencing blood sugar metabolism and blood fats, inflammation, and oxidative stress in individuals with prediabetes and T2DM. Hence Nigella supplementation has promsing potential as an adjunct therapeutic in the management of prediabetes and T2DM.
Abstract
OBJECTIVE Nigella sativa (N. sativa) from the family Ranunculaceae has medicinal properties. Previous studies have reported promising findings showing that N. sativa may benefit cardiometabolic health; however, current evidence on its cardiometabolic effects on those with prediabetes and type 2 diabetes mellitus (T2DM) is still unclear. Hence, we conducted a systematic review and meta-analysis to assess the efficacy of N. sativa on cardiometabolic parameters in population with prediabetes and T2DM. METHODS PubMed/Medline, ISI Web of Science, Scopus, and Cochrane library were systematically searched up to June 20, 2022. Meta-analyses using random-effects models were used. RESULTS Eleven randomized controlled trials (RCTs) were included in the meta-analysis. N. sativa intervention resulted in significant changes in fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), c-reactive protein (CRP), and malondialdehyde (MDA), without overall changes in glucose levels after oral glucose tolerance test (OGTT), fasting insulin, homeostatic model assessment of insulin resistance (HOMA-IR), triglyceride, high-density lipoprotein cholesterol (HDL-C), and body mass index (BMI) when compared with the control group. In subgroup analyses, N. sativa supplementation enhanced serum levels of HDL-C in subjects with baseline HDL-C lower than 40 mg/dL. Furthermore, HOMA-IR and BMI values decreased in the N. sativa-supplemented group compared with the control group, when the length of follow-up was more than 8 weeks and the dose was more than 1 g/day for N. sativa supplementation, respectively. CONCLUSION Our findings indicate that N. sativa supplementation may effectively improve cardiometabolic profiles in individuals with prediabetes and T2DM.
-
4.
Cinnamon as a Complementary Therapeutic Approach for Dysglycemia and Dyslipidemia Control in Type 2 Diabetes Mellitus and Its Molecular Mechanism of Action: A Review.
Silva, ML, Bernardo, MA, Singh, J, de Mesquita, MF
Nutrients. 2022;14(13)
-
-
-
Free full text
Plain language summary
Diabetes is a metabolic disorder resulting from defects in insulin secretion and/or action, leading to chronic hyperglycaemia, which has an adverse impact on health. The aim of this study was to provide an overview of the beneficial effects of cinnamon in exerting dysglycemia and dyslipidaemia control in type 2 diabetic patients and a summary of its mechanisms of action. This study is a narrative review of twenty-three articles. Results showed that: - in diabetic patients with dyslipidaemia, the lipid profile could be modulated with cinnamon supplementation as it seems to decrease serum triglycerides, total cholesterol and low-density lipoprotein levels. - cinnamon seems to exert beneficial and protective anti-inflammatory and antioxidant effects. - cinnamon seems to be effective as an antihyperlipidemic agent – through the regulation of lipid metabolism in enterocyte [a cell of the intestinal lining]. Authors conclude that targeted cinnamon-based therapy can provide an opportunity to modulate glucose and lipid dysregulation to avoid the progression of T2DM. Thus, future research studies should investigate the effect of cinnamon by employing a larger number of standardized randomized clinical trials to provide a comprehensive impact of cinnamon on diabetic patients.
Abstract
The scientific evidence that cinnamon may exert beneficial effects on type 2 diabetes mellitus due to the biological activity of its bioactive compounds has been increasing in recent years. This review provides an overview of the effects of cinnamon on clinical parameters of diabetes and summarizes the molecular mechanisms of action of cinnamon on glucose and lipid metabolism. Search criteria include an electronic search using PubMed, Medline, and Cochrane Library databases. English literature references from 2000 up to 2022 were included. Following title and abstract review, full articles that met the inclusion criteria were included. The results from the available evidence revealed that cinnamon improved glycemic and lipidemic indicators. Clinical trials clarified that cinnamon also possesses an anti-inflammatory effect, which may act beneficially in diabetes. Based on in vitro and in vivo studies, cinnamon seems to elicit the regulation of glucose metabolism in tissues by insulin-mimetic effect and enzyme activity improvement. Furthermore, cinnamon seems to decrease cholesterol and fatty acid absorption in the gut. The current literature search showed a considerable number of studies on diabetic subjects. Some limitations in comparing published data should be highlighted, including variability in doses, extracts and species of cinnamon, administration forms, and antidiabetic therapy.
-
5.
Effect of Vitamin D Supplementation on Obesity-Induced Insulin Resistance: A Double-Blind, Randomized, Placebo-Controlled Trial.
Cefalo, CMA, Conte, C, Sorice, GP, Moffa, S, Sun, VA, Cinti, F, Salomone, E, Muscogiuri, G, Brocchi, AAG, Pontecorvi, A, et al
Obesity (Silver Spring, Md.). 2018;26(4):651-657
-
-
-
Free full text
-
Plain language summary
Vitamin D concentration has been inversely associated with impaired glucose regulation, insulin resistance and risk of metabolic dysfunction. The aim of the study was to evaluate whether Vitamin D supplementation could improve insulin sensitivity in patients with a high risk of diabetes. The study is a randomised, double-blind, placebo-controlled trial. The participants with obesity were supplemented with Vitamin D or placebo on top of a hypocaloric diet. Results indicate that Vitamin D supplementation combined with weight loss is linked with a significant improvement in insulin sensitivity in vitamin D deficient participants with obesity.
Abstract
OBJECTIVE The aim was to investigate whether vitamin D supplementation, combined with a hypocaloric diet, could have an independent effect on insulin sensitivity in subjects with both overweight and hypovitaminosis D. Changes from baseline in anthropometric parameters, body composition, glucose tolerance, and insulin secretion were considered as secondary outcomes. METHODS Eighteen volunteers who were nondiabetic and vitamin D deficient and had BMI > 25 kg/m2 were randomized (1:1) in a double-blind manner to a hypocaloric diet + either oral cholecalciferol at 25,000 IU/wk or placebo for 3 months. Hyperinsulinemic-euglycemic clamp to measure insulin sensitivity was performed at baseline and after intervention. RESULTS Body weight in both groups decreased significantly (-7.5% in the vitamin D group and -10% in the placebo group; P < 0.05 for both), with no between-group differences. Serum 25-hydroxyvitamin D levels in the vitamin D group increased considerably (from 36.7 ± 13.2 nmol/L to 74.8 ± 18.7 nmol/L; P < 0.001). Insulin sensitivity in the vitamin D group improved (from 4.6 ± 2.0 to 6.9 ± 3.3 mg·kg-1 ·min-1 ; P < 0.001), whereas no changes were observed in the placebo group (from 4.9 ± 1.1 to 5.1 ± 0.3 mg·kg-1 ·min-1 ; P = 0.84). CONCLUSIONS Cholecalciferol supplementation, combined with a weight loss program, significantly improves insulin sensitivity in healthy subjects with obesity and might represent a personalized approach for insulin-resistant subjects with obesity.
-
6.
A whole-grain diet reduces peripheral insulin resistance and improves glucose kinetics in obese adults: A randomized-controlled trial.
Malin, SK, Kullman, EL, Scelsi, AR, Haus, JM, Filion, J, Pagadala, MR, Godin, JP, Kochhar, S, Ross, AB, Kirwan, JP
Metabolism: clinical and experimental. 2018;82:111-117
-
-
-
Free full text
-
Plain language summary
Literature shows that dietary whole-grain intake is associated with a lower incidence of type 2 diabetes. The aim of the study was to investigate the association between a whole-grain diet and insulin resistance and glucose use in individuals at risk for type 2 diabetes. The study was a randomized, double-blind, controlled crossover trial involving fourteen middle-aged, obese adults at risk for diabetes. Randomisation was carried out prior to metabolic testing. Results indicate that whole-grain intake as part of a mixed-meal diet significantly improved post-prandial (after a meal) glucose metabolism in middle-aged obese adults. Furthermore, both whole-grain and refined-grain interventions induced about 3–6% weight and fat loss. Authors conclude that whole-grain intake effectively promotes glycaemic control by improving insulin action.
Abstract
BACKGROUND Whole-grain intake is associated with lower risk of type 2 diabetes but the mechanisms are unclear. PURPOSE We tested the hypothesis that a WG diet reduces insulin resistance and improves glucose use in individuals at risk for type 2 diabetes compared with an isocaloric-matched refined-grain diet. METHODS A double-blind, randomized, controlled, crossover trial of 14 moderately obese adults (Age, 38 ± 2 y; BMI, 34.0 ± 1.1 kg/m2). Insulin resistance and glucose metabolism was assessed using an oral glucose tolerance test combined with isotopic tracers of [6,6-2H2]-glucose and [U-13C]-glucose, and indirect calorimetry. Peripheral and hepatic insulin resistance was assessed as 1/(rate of disposal/insulin), and endogenous glucose rates of appearance (Ra) iAUC60-240 × insulin iAUC60-240, respectively. Both diets met ADA nutritional guidelines and contained either whole-grain (50 g per 1000 kcal) or equivalent refined-grain. All food was provided for 8 wk. with an 8-10 wk. washout period between diets. RESULTS Post-prandial glucose tolerance, peripheral insulin sensitivity, and metabolic flexibility (insulin-stimulated - fasting carbohydrate oxidation) improvements were greater after whole-grain compared to the refined-grain diet (P < 0.05). Compared to baseline, body fat (~2 kg) and hepatic Ra insulin resistance was reduced by both diets, while fasting glucose and exogenous glucose-meal were unchanged after both interventions. Changes in peripheral insulin resistance and metabolic flexibility correlated with improved glucose tolerance (P < 0.05). CONCLUSION Whole-grains reduced diabetes risk and the mechanisms appear to work through reduced post-prandial blood glucose and peripheral insulin resistance that were statistically linked to enhanced metabolic flexibility.
-
7.
Bread Affects Clinical Parameters and Induces Gut Microbiome-Associated Personal Glycemic Responses.
Korem, T, Zeevi, D, Zmora, N, Weissbrod, O, Bar, N, Lotan-Pompan, M, Avnit-Sagi, T, Kosower, N, Malka, G, Rein, M, et al
Cell metabolism. 2017;25(6):1243-1253.e5
-
-
-
Free full text
Plain language summary
Bread is a key ingredient of the human diet. Wheat is the most commonly used cereal for baking bread. The aim of this study was to compare the effects of traditionally milled and prepared whole-grain sourdough bread and industrial white bread made from refined wheat on multiple clinical and disease markers and on the composition and function of the gut microbiome. The study is a randomized crossover trial with 20 healthy subjects. Participants received either industrial white bread made from mostly refined wheat flour or a sourdough-leavened bread made from whole-grain wheat flour. Results indicate that there were no significant differences on a broad array of clinical parameters between the two 1-week-long dietary interventions. Additionally, gut microbiome analysis showed that the microbiota composition remained generally stable and person specific throughout the trial. Authors conclude that their study underlines the importance of personalisation in dietary recommendations as the interpersonal variation in the effect of bread would allow the personalisation of bread-related nutritional recommendations and optimisation of food choices worldwide.
Abstract
Bread is consumed daily by billions of people, yet evidence regarding its clinical effects is contradicting. Here, we performed a randomized crossover trial of two 1-week-long dietary interventions comprising consumption of either traditionally made sourdough-leavened whole-grain bread or industrially made white bread. We found no significant differential effects of bread type on multiple clinical parameters. The gut microbiota composition remained person specific throughout this trial and was generally resilient to the intervention. We demonstrate statistically significant interpersonal variability in the glycemic response to different bread types, suggesting that the lack of phenotypic difference between the bread types stems from a person-specific effect. We further show that the type of bread that induces the lower glycemic response in each person can be predicted based solely on microbiome data prior to the intervention. Together, we present marked personalization in both bread metabolism and the gut microbiome, suggesting that understanding dietary effects requires integration of person-specific factors.
-
8.
Sucralose affects glycemic and hormonal responses to an oral glucose load.
Pepino, MY, Tiemann, CD, Patterson, BW, Wice, BM, Klein, S
Diabetes care. 2013;36(9):2530-5
-
-
-
Free full text
-
Plain language summary
Non-nutritive sweeteners (NNS) are food additives that provide a sweet taste to food but have few, if any, calories. Currently, seven NNS (sucralose, saccharin, aspartame, acesulfame potassium, neotame, stevia, and Luo han guo extract) are approved by the U.S. Food and Drug Administration and are widely used in thousands of food products. The aim of this study was to analyse whether sucralose ingestion alters the glycaemic and hormonal responses to glucose ingestion in obese subjects who are not regular users of NNS. Seventeen participants who were obese but not insulin resistant participated in the study. They were studied on two separate occasions, 7 days apart, in a crossover design. Sucralose was used as it matches the sweetness of a typical diet soda and also stimulates glucagon-like peptide 1 [a type of peptide hormone] secretion. Results demonstrate that: - the ingestion of sucralose alters the metabolic response to an oral glucose load in obese people who are not regular consumers of NNS. - insulin clearance from plasma was slower after sucralose than after water ingestion. - glucose-induced glucagon [hormone that helps control blood sugar levels] suppression was the same after both sucralose and water ingestion Authors conclude that sucralose is not metabolically inert but has physiologic effects.
Abstract
OBJECTIVE Nonnutritive sweeteners (NNS), such as sucralose, have been reported to have metabolic effects in animal models. However, the relevance of these findings to human subjects is not clear. We evaluated the acute effects of sucralose ingestion on the metabolic response to an oral glucose load in obese subjects. RESEARCH DESIGN AND METHODS Seventeen obese subjects (BMI 42.3 ± 1.6 kg/m(2)) who did not use NNS and were insulin sensitive (based on a homeostasis model assessment of insulin resistance score ≤ 2.6) underwent a 5-h modified oral glucose tolerance test on two separate occasions preceded by consuming either sucralose (experimental condition) or water (control condition) 10 min before the glucose load in a randomized crossover design. Indices of β-cell function, insulin sensitivity (SI), and insulin clearance rates were estimated by using minimal models of glucose, insulin, and C-peptide kinetics. RESULTS Compared with the control condition, sucralose ingestion caused 1) a greater incremental increase in peak plasma glucose concentrations (4.2 ± 0.2 vs. 4.8 ± 0.3 mmol/L; P = 0.03), 2) a 20 ± 8% greater incremental increase in insulin area under the curve (AUC) (P < 0.03), 3) a 22 ± 7% greater peak insulin secretion rate (P < 0.02), 4) a 7 ± 4% decrease in insulin clearance (P = 0.04), and 5) a 23 ± 20% decrease in SI (P = 0.01). There were no significant differences between conditions in active glucagon-like peptide 1, glucose-dependent insulinotropic polypeptide, glucagon incremental AUC, or indices of the sensitivity of the β-cell response to glucose. CONCLUSIONS These data demonstrate that sucralose affects the glycemic and insulin responses to an oral glucose load in obese people who do not normally consume NNS.