The Effects of Almonds on Gut Microbiota,Glycometabolism, and Inflammatory Markers in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

The use of nutritional interventions for managing diabetes is one of the effective strategies aimed at reducing the global prevalence of the condition, which is on the rise. Almonds are the most consumed tree nut and they are known to be rich sources of protein, monounsaturated fatty acids, essential minerals, and dietary fibre. Therefore, the aim of this review was to evaluate the effects of almonds on gut microbiota, glycometabolism, and inflammatory parameters in patients with type 2 diabetes. Methods: This systematic review and meta-analysis was carried out according to the preferred reporting items for systematic review and meta-analysis (PRISMA). EBSCOhost, which encompasses the Health Sciences Research Databases; Google Scholar; EMBASE; and the reference lists of articles were searched based on population, intervention, control, outcome, and study (PICOS) framework. Searches were carried out from database inception until 1 August 2021 based on medical subject headings (MesH) and synonyms. The meta-analysis was carried out with the Review Manager (RevMan) 5.3 software. Results: Nine randomised studies were included in the systematic review and eight were used for the meta-analysis. The results would suggest that almond-based diets have significant effects in promoting the growth of short-chain fatty acid (SCFA)-producing gut microbiota. Furthermore, the meta-analysis showed that almond-based diets were effective in significantly lowering (p < 0.05) glycated haemoglobin (HbA1c) levels and body mass index (BMI) in patients with type 2 diabetes. However, it was also found that the effects of almonds were not significant (p > 0.05) in relation to fasting blood glucose, 2 h postprandial blood glucose, inflammatory markers (C-reactive protein and Tumour necrosis factor α, TNF-α), glucagon-like peptide-1 (GLP-1), homeostatic model assessment of insulin resistance (HOMA–IR), and fasting insulin. The biological mechanisms responsible for the outcomes observed in this review in relation to reduction in HbA1c and BMI may be based on the nutrient composition of almonds and the biological effects, including the high fibre content and the low glycaemic index profile. Conclusion: The findings of this systematic review and meta-analysis have shown that almond-based diets may be effective in promoting short-chain fatty acid-producing bacteria and lowering glycated haemoglobin and body mass index in patients with type 2 diabetes compared with control. However, the effects of almonds were not significant (p > 0.05) with respect to fasting blood glucose, 2 h postprandial blood glucose, inflammatory markers (C-reactive protein and TNF-α), GLP-1, HOMA–IR, and fasting insulin.     

The Effect of Prebiotics and Oral Anti-Diabetic Agents on Gut Microbiome in Patients with Type 2 Diabetes: A Systematic Review and Network Meta-Analysis of Randomised Controlled Trials

Background: Nutritional interventions such as the use of prebiotics can promote eubiosis of gut microbiome and maintain glucose homeostasis in patients with type 2 diabetes (T2D). However, it would appear that results of the effects of prebiotics on the community of microbes in the gut are not consistent. Aim: To examine the effect of prebiotics and oral antidiabetic agents on gut microbiome in patients with T2D. Methods: The PRISMA Extension Statement for Systematic Reviews and Network Meta-analyses was used to conduct this review. Searches were carried out in EMBASE, EBSCO-host databases, Google Scholar and the reference lists of articles for studies that are relevant to the research question, from database inception to 15 August 2022. The search strategy was based on PICOS framework. Network Meta-analysis which allows the estimation of relative treatment effects by combing both direct trial evidence (e.g., treatment A vs. treatment B) and indirect evidence was conducted. Furthermore, pairwise meta-analysis was also carried out to estimate effect sizes based on head-to-head comparisons of treatments and/or control conditions. Results: Findings of the Network meta-analysis revealed that prebiotics significantly reduced HbA1c compared with control and the SMD was −0.43 [95% CI, −0.77, −0.08; p = 0.02], whereas there was no significant difference (p > 0.05) between the other treatments and control. In addition, anti-diabetic agents including glipizide and metformin also reduced HbA1C, although these were not significantly different (p > 0.05) from control. While prebiotics promoted Bifidobacterium and Akkermansia, the improvements were not significantly different (p > 0.05) from control. On the other hand, metformin decreased the relative abundance of Bifidobacterium, but increased Lactobacillus and Akkermansia, although the differences were not significant (p > 0.05) compared with control. With respect to fasting blood glucose and BMI, the effects of prebiotics and oral antidiabetic agents did not differ significantly (p > 0.05) from controls. Conclusions: The findings of the systematic review and Network meta-analysis demonstrated prebiotics were significantly (p < 0.05) more effective in reducing HbA1c than control in patients with T2D. However, the effects of prebiotics and oral antidiabetic agents did not differ significantly (p > 0.05) from the controls in relation to fasting blood glucose, post-prandial blood glucose, body mass index and the genera of gut bacteria examined. More studies are required to fully investigate the effects of prebiotics and oral antidiabetic agents in patients with T2D     

Effects of Smoking on the Gut Microbiota in Individuals with Type 2 Diabetes Mellitus

Smoking affects eating habits; however, few studies on smoking and the gut microbiota have reported the effects of diet in detail. This cross-sectional study aimed to determine the association between smoking and the gut microbiota, considering the impact of smoking on dietary intake. Dietary habits and the composition of the gut microbiota were assessed in 195 men with type 2 diabetes (164 non-current smokers and 31 current smokers) using a brief self-administered diet history questionnaire and 16S ribosomal RNA gene sequencing of fecal samples. The data were compared according to the current smoking status of the participants. Current smokers had high alcohol and sugar/sweetener intake and low fruit intake. The proportion of the Coprococcus genus was higher among current smokers. Multiple regression analysis adjusted for current smoking, age, exercise habits, alcohol intake, sugar and sweetener intake, and fruit intake showed that smoking was associated with the proportion of the Coprococcus genus. Current smoking was associated with both dietary intake and composition of the gut microbiota. Although dietary intake should be considered when investigating the association between smoking and the gut microbiota, the results suggest that the direct effect of smoking is more significant.     

Gut Microbiota and Subclinical Cardiovascular Disease in Patients with Type 2 Diabetes Mellitus

Type 2 diabetes (T2D) is associated with an increased risk of cardiovascular disease (CVD). The gut microbiota may contribute to the onset and progression of T2D and CVD. The aim of this study was to evaluate the relationship between the gut microbiota and subclinical CVD in T2D patients. This cross-sectional study used echocardiographic data to evaluate the cardiac structure and function in T2D patients. We used a quantitative polymerase chain reaction to measure the abundances of targeted fecal bacterial species that have been associated with T2D, including Bacteroidetes, Firmicutes, Clostridium leptum group, Faecalibacterium prausnitzii, Bacteroides, Bifidobacterium, Akkermansia muciniphila, and Escherichia coli. A total of 155 subjects were enrolled (mean age 62.9 ± 10.1 years; 57.4% male and 42.6% female). Phyla Bacteroidetes and Firmicutes and genera Bacteroides were positively correlated with the left ventricular ejection fraction. Low levels of phylum Firmicutes were associated with an increased risk of left ventricular hypertrophy. High levels of both phylum Bacteroidetes and genera Bacteroides were negatively associated with diastolic dysfunction. A high phylum Firmicutes/Bacteroidetes (F/B) ratio and low level of genera Bacteroides were correlated with an increased left atrial diameter. Phyla Firmicutes and Bacteroidetes, the F/B ratio, and the genera Bacteroides were associated with variations in the cardiac structure and systolic and diastolic dysfunction in T2D patients. These findings suggest that changes in the gut microbiome may be the potential marker of the development of subclinical CVD in T2D patients.     

Prolonged Isolated Soluble Dietary Fibre Supplementation in Overweight and Obese Patients: A Systematic Review with Meta-Analysis of Randomised Controlled Trials

The prevalence of overweight and obesity is rising rapidly, currently affecting 1.9 billion adults worldwide. Prebiotic dietary fibre supplementation is a promising approach to improve weight loss and reduce metabolic complications in overweight and obese subjects due to modifications of the microbiota composition and function. Previous systematic reviews and meta-analyses addressing similar questions revealed discordant evidence and/or are outdated. We searched MEDLINE, Embase, Google Scholar, and forward and backward citations for randomised controlled trials (RCTs) with isolated soluble dietary fibre supplementation for at least 12 weeks in overweight and obese patients measuring body weight, published through April 2022. We expressed the results as mean differences (MDs) using the random-effects model of the metafor package in R and assessed risk of bias using the Cochrane RoB2 tool. We conducted the study according to the PRISMA guidelines and registered the protocol on PROSPERO (CRD42022295246). The participants with dietary fibre supplementation showed a significantly higher reduction in body weight (MD −1.25 kg, 95% CI −2.24, −0.25; 27 RCTs; 1428 participants) accompanied by a significant decrease in BMI, waist circumference, fasting blood insulin, and HOMA-IR compared to the control group. Certainty of evidence was high, paving the way for the implementation of isolated soluble dietary fibre supplementation into clinical practice.     

Habitual Dietary Fiber Intake,Fecal Microbiota,and Hemoglobin A1c Level in Chinese Patients with Type 2 Diabetes

High-fiber diet interventions have been proven to be beneficial for gut microbiota and glycemic control in diabetes patients. However, the effect of a low level of fiber in habitual diets remains unclear. This study aims to examine the associations of habitual dietary fiber intake with gut microbiome profiles among Chinese diabetes patients and identify differential taxa that mediated associations of dietary fiber with HbA1c level. Two cross-sectional studies and one longitudinal study were designed based on two follow-up surveys in a randomized trial conducted during 2015–2017. The study included 356 and 310 participants in the first and second follow-ups, respectively, with 293 participants in common in both surveys. Dietary fiber intake was calculated based on a 3-day 24-h diet recall at each survey and was classified into a lower or a higher group according to the levels taken based on the two surveys using 7.2 g/day as a cut-off value. HbA1c was assayed to assess glycemic status using a cut-off point of 7.0% and 8.0%. Microbiome was profiled by 16S rRNA sequencing. A high habitual dietary fiber intake was associated with a decrease in α-diversity in both the cross-sectional and longitudinal analyses. At the first follow–up, phylum Firmicutes and Fusobacteria were negatively associated with a higher dietary fiber intake (p < 0.05, Q < 0.15); at the second follow-up, genus Adlercreutzia, Prevotella, Ruminococcus, and Desulfovibrio were less abundant in patients taking higher dietary fiber (p < 0.05, Q < 0.15); genus Desulfovibrio and Ruminococcaceae (Unknown), two identified differential taxa by HbA1c level, were negatively associated with dietary fiber intake in both the cross-sectional and longitudinal analyses, and mediated the dietary fiber-HbA1c associations among patients taking dietary fiber ≥ 7.2 g/day (mediation effect β [95%CI]: −0.019 [−0.043, −0.003], p = 0.018 and −0.019 [−0.046, −0.003], p = 0.016). Our results suggest that habitual dietary fiber intake has a beneficial effect on gut microbiota in Chinese diabetes patients. Further studies are needed to confirm our results.     

Unique Habitual Food Intakes in the Gut Microbiota Cluster Associated with Type 2 Diabetes Mellitus

This cross-sectional study aimed to clarify the characteristic gut microbiota of Japanese patients with type 2 diabetes (T2DM) using t-distributed stochastic neighbor embedding analysis and the k-means method and to clarify the relationship with background data, including dietary habits. The gut microbiota data of 383 patients with T2DM and 114 individuals without T2DM were classified into red, blue, green, and yellow groups. The proportions of patients with T2DM in the red, blue, green, and yellow groups was 86.8% (112/129), 69.8% (81/116), 76.3% (90/118), and 74.6% (100/134), respectively; the red group had the highest prevalence of T2DM. There were no intergroup differences in sex, age, or body mass index. The red group had higher percentages of the Bifidobacterium and Lactobacillus genera and lower percentages of the Blautia and Phascolarctobacterium genera. Higher proportions of patients with T2DM in the red group used α-glucosidase inhibitors and glinide medications and had a low intake of fermented soybean foods, including miso soup, than those in the other groups. The gut microbiota pattern of the red group may indicate characteristic changes in the gut microbiota associated with T2DM in Japan. These results also suggest that certain diabetes drugs and fermented foods may be involved in this change. Further studies are needed to confirm the relationships among traditional dietary habits, the gut microbiota, and T2DM in Japan.     

Effects of Synbiotic Supplementation on Chronic Inflammation and the Gut Microbiota in Obese Patients with Type 2 Diabetes Mellitus: A Randomized Controlled Study

The aim of this study was to investigate the effects of 24-week synbiotic supplementation on chronic inflammation and the gut microbiota in obese patients with type 2 diabetes. We randomized 88 obese patients with type 2 diabetes to one of two groups for 24 weeks: control or synbiotic (Lacticaseibacillus paracasei strain Shirota (previously Lactobacillus casei strain Shirota) and Bifidobacterium breve strain Yakult, and galactooligosaccharides). The primary endpoint was the change in interleukin-6 from baseline to 24 weeks. Secondary endpoints were evaluation of the gut microbiota in feces and blood, fecal organic acids, high-sensitivity C-reactive protein, lipopolysaccharide-binding protein, and glycemic control. Synbiotic administration for 24 weeks did not significantly affect changes in interleukin-6 from baseline to 24 weeks (0.35 ± 1.99 vs. −0.24 ± 1.75 pg/mL, respectively). Relative to baseline, however, at 24 weeks after synbiotic administration there were positive changes in the counts of Bifidobacterium and total lactobacilli, the relative abundances of Bifidobacterium species such as Bifidobacterium adolescentis and Bifidobacterium pseudocatenulatum, and the concentrations of acetic and butyric acids in feces. No significant changes in inflammatory markers were found in the synbiotic group compared to the control group. However, synbiotic administration at least partially improved the gut environment in obese patients with type 2 diabetes.     

Dietary Fibre Intervention for Gut Microbiota,Sleep, and Mental Health in Adults with Irritable Bowel Syndrome: A Scoping Review

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder affecting 4–5% of the global population. This disorder is associated with gut microbiota, diet, sleep, and mental health. This scoping review therefore aims to map existing research that has administrated fibre-related dietary intervention to IBS individuals and reported outcomes on at least two of the three following themes: gut microbiota, sleep, and mental health. Five digital databases were searched to identify and select papers as per the inclusion and exclusion criteria. Five articles were included in the assessment, where none reported on all three themes or the combination of gut microbiota and sleep. Two studies identified alterations in gut microbiota and mental health with fibre supplementation. The other three studies reported on mental health and sleep outcomes using subjective questionnaires. IBS-related research lacks system biology-type studies targeting gut microbiota, sleep, and mental health in patients undergoing diet intervention. Further IBS research is required to explore how human gut microbiota functions (such as short-chain fatty acids) in sleep and mental health, following the implementation of dietary pattern alteration or component supplementation. Additionally, the application of objective sleep assessments is required in order to detect sleep change with more accuracy and less bias.     

Oleuropein Ameliorates Advanced Stage of Type 2 Diabetes in db/db Mice by Regulating Gut Microbiota

Previous studies have reported the therapeutic effects of oleuropein (OP) consumption on the early stage of type 2 diabetes. However, the efficacy of OP on the advanced stage of type 2 diabetes has not been investigated, and the relationship between OP and intestinal flora has not been studied. Therefore, in this study, to explore the relieving effects of OP intake on the advanced stage of type 2 diabetes and the regulatory effects of OP on intestinal microbes, diabetic db/db mice (17-week-old) were treated with OP at the dose of 200 mg/kg for 15 weeks. We found that OP has a significant effect in decreasing fasting blood glucose levels, improving glucose tolerance, lowering the homeostasis model assessment–insulin resistance index, restoring histopathological features of tissues, and promoting hepatic protein kinase B activation in db/db mice. Notably, OP modulates gut microbiota at phylum level, increases the relative abundance of Verrucomicrobia and Deferribacteres, and decreases the relative abundance of Bacteroidetes. OP treatment increases the relative abundance of Akkermansia, as well as decreases the relative abundance of Prevotella, Odoribacter, Ruminococcus, and Parabacteroides at genus level. In conclusion, OP may ameliorate the advanced stage of type 2 diabetes through modulating the composition and function of gut microbiota. Our findings provide a promising therapeutic approach for the treatment of advanced stage type 2 diabetes.     

Effect of Dietary Protein and Processing on Gut Microbiota—A Systematic Review

The effect of diet on the composition of gut microbiota and the consequent impact on disease risk have been of expanding interest. The present review focuses on current insights of changes associated with dietary protein-induced gut microbial populations and examines their potential roles in the metabolism, health, and disease of animals. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) protocol was used, and 29 highly relevant articles were obtained, which included 6 mouse studies, 7 pig studies, 15 rat studies, and 1 in vitro study. Analysis of these studies indicated that several factors, such as protein source, protein content, dietary composition (such as carbohydrate content), glycation of protein, processing factors, and protein oxidation, affect the digestibility and bioavailability of dietary proteins. These factors can influence protein fermentation, absorption, and functional properties in the gut and, consequently, impact the composition of gut microbiota and affect human health. While gut microbiota can release metabolites that can affect host physiology either positively or negatively, the selection of quality of protein and suitable food processing conditions are important to have a positive effect of dietary protein on gut microbiota and human health.     

Role of Gut Microbiota on Onset and Progression of Microvascular Complications of Type 2 Diabetes (T2DM)

Type 2 diabetes mellitus (T2DM) remains one of the most problematic and economic consumer disorders worldwide, with growing prevalence and incidence. Over the last years, substantial research has highlighted the intricate relationship among gut microbiota, dysbiosis and metabolic syndromes development. Changes in the gut microbiome composition lead to an imbalanced gastrointestinal habitat which promotes abnormal production of metabolites, inflammatory status, glucose metabolism alteration and even insulin resistance (IR). Short-chain fatty acids (SCFAs), trimethylamine N-oxide (TMAO), lipopolysaccharide, aromatic amino acids and their affiliated metabolites, contribute to T2DM via different metabolic and immunologic pathways. In this narrative review, we discuss the immunopathogenic mechanism behind gut dysbiosis, T2DM development and the major known diabetic microvascular complications (retinopathy, neuropathy and nephropathy), the beneficial use of pre- and pro-biotics and fecal microbiota transplantation in T2DM management and new findings and future perspectives in this field.     

Habitual Dietary Intake Affects the Altered Pattern of Gut Microbiome by Acarbose in Patients with Type 2 Diabetes

The aim of this research was to reveal the characteristics of gut microbiome altered by acarbose intervention in Japanese patients with type 2 diabetes (T2D) and its possible association with habitual dietary intake. Eighteen patients with T2D were administered acarbose for four weeks. The abundances of two major phyla, namely Actinobacteria and Bacteroidetes, were reciprocally changed accompanied by the acarbose intervention. There were also significant changes in the abundances of ten genera, including the greater abundance of Bifidobacterium, Eubacterium, and Lactobacillus and the lower abundance of Bacteroides in the group after the intervention than that before the intervention. Hierarchical clustering of habitual dietary intake was performed based on the pattern of changes in the gut microbiota and were classified into distinct three clusters. Cluster I consisted of sucrose, cluster II mainly included fat intake, and cluster III mainly included carbohydrate intake. Moreover, the amount of change in Faecalibacterium was positively correlated with the intake of rice, but negatively correlated with the intake of bread. The intake of potato was negatively correlated with the amount of change in Akkermansia and Subdoligranulum. Acarbose altered the composition of gut microbiome in Japanese patients with T2D, which might be linked to the habitual dietary intake.     

The Effect of Resveratrol on Blood Lipid Profile: A Dose-Response Meta-Analysis of Randomized Controlled Trials

(1) Background: The effects of resveratrol on blood lipids are controversial. Whether there is a dose-response of the lipid profile upon resveratrol supplementation is unknown. (2) Methods: This dose-response meta-analysis of randomized controlled trials (RCTs) was performed to explore the effects of resveratrol supplementation on lipid profile. A systematical and comprehensive search of several databases was conducted by 30 June 2022. (3) Results: The results indicated that the intake of resveratrol could significantly decrease the total cholesterol (TC) (mean difference = −10.28; 95%CI: −13.79, −6.76, p < 0.001), triglyceride (TG) (Mean difference = −856; 95%CI: −12.37, −4.75, p < 0.001) and low-density lipoprotein cholesterol (LDL-C) (mean difference = −5.69; 95%CI: −11.07, −0.31, p = 0.038) level, but did not alter the level of high-density lipoprotein cholesterol (HDL-C). In the non-linear dose–response analysis, we observed a significant effect of the supplementation dosage on the level of LDL-C (p-nonlinearity = 0.002). Results from the sub-group analysis showed that the reduction of LDL-C was more significant in the trials with a duration of ≥12 weeks and in subjects with type 2 diabetes mellitus. (4) Conclusion: Findings from this study suggest that resveratrol may be beneficial to reduce TC, TG, and LDL-C levels in the blood. The dosage of the resveratrol intervention is an essential factor that affects the level of LDL-C.     

The Effect of Vitamin D Supplementation on Glycemic Control and Lipid Profile in Patients with Type 2 Diabetes Mellitus

Aim: The aim of this study was to evaluate the effect of vitamin D supplementation in patients with type 2 diabetes mellitus (T2DM) with regard to their glycemic control and lipid profile.

Methods: One hundred subjects with T2DM were recruited and given 4500 IU/day of vitamin D for 2 months. 25-Hydroxyvitamin D [25(OH)D], fasting blood glucose (FBG), glycosylated hemoglobin A1c (HbA1c), and lipid profile were measured pre- and postsupplementation.

Results: There was a significant increase in the mean value of 25(OH)D level after supplementation (baseline level 16 ± 5.3 ng/ml vs. after supplement level 49.2 ± 17.7 ng/ml, p < 0.05). Both FBG and HbA1c but not lipid profile were significantly decreased after supplementation. However, the univariate general linear model between 25(OH)D percentiles and lipid profile levels showed that diabetic subjects with high 25(OH)D levels (>61 ng/ml) had significantly lower levels of total cholesterol and low-density lipoprotein cholesterol (LDL-C) in comparison to those in the low or middle percentiles. Furthermore, participants in a higher percentile had a significantly higher level of high-density lipoprotein cholesterol (HDL-C) than those in the middle percentile. Lipid profile levels were not affected by the supplement except for triglycerides (TG) levels in females, which were significantly decreased.

Conclusions: Vitamin D supplementation may be beneficial to diabetic subjects because it improved glycemic control. Diabetic subjects with high 25(OH)D levels (>61 ng/ml) had better lipid profiles.     

The Metabolic Effects of Oats Intake in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis

The present study aimed to comprehensively assess if oats intake is beneficial for diabetic patients. The literature search was conducted in PubMed database up to 23 August 2015. Fourteen controlled trials and two uncontrolled observational studies were included. Compared with the controls, oats intake significantly reduced the concentrations of glycosylated hemoglobin A1c (HbA1c) (MD, −0.42%; 95% CI, −0.61% to −0.23%), fasting blood glucose (FBG) (MD, −0.39 mmol/L; 95% CI, −0.58 to −0.19 mmol/L), total cholesterol (TC) (MD, −0.49 mmol/L; 95% CI, −0.86 to −0.12 mmol/L), low-density lipoprotein cholesterol (LDL-C) (MD, −0.29 mmol/L; 95% CI, −0.48 to −0.09 mmol/L). Oatmeal significantly reduced the acute postprandial glucose and insulin responses compared with the control meal. The present study has revealed a beneficial effect of oats intake on glucose control and lipid profiles in type 2 diabetic patients. Further investigations of oats intake in patients with type 1 diabetes and the safety of oats consumption are required.     

Bifidobacterium adolescentis Is Effective in Relieving Type 2 Diabetes and May Be Related to Its Dominant Core Genome and Gut Microbiota Modulation Capacity

The prevalence of diabetes mellitus is increasing globally. Probiotics have been shown to be an effective intervention for diabetes. This study focused on the relieving effects and possible mechanisms of 16 strains of two dominant Bifidobacterium species (B. bifidum and B. adolescentis, which exist in the human gut at different life stages) on type 2 diabetes (T2D). The results indicated that more B. adolescentis strains appeared to be superior in alleviating T2D symptoms than B. bifidum strains. This effect was closely related to the ability of B. adolescentis to restore the homeostasis of the gut microbiota, increase the abundance of short-chain fatty acid-producing flora, and alleviate inflammation in mice with T2D. In addition, compared with B. bifidum, B. adolescentis had a higher number of core genes, and these genes were more evolutionarily stable, including unique environmental tolerance, carbon and nitrogen utilization genes, and a blood sugar regulation gene, glgP. This may be one of the reasons why B. adolescentis is more likely to colonize in the adult gut and show a superior ability to relieve T2D. This study provides insights into future studies aimed at investigating probiotics for the treatment of metabolic diseases.     

Comparison of the Effectiveness of Low Carbohydrate Versus Low Fat Diets,in Type 2 Diabetes: Systematic Review and Meta-Analysis of Randomized Controlled Trials

The clinical benefit of low carbohydrate (LC) diets compared with low fat (LF) diets for people with type 2 diabetes (T2D) remains uncertain. We conducted a meta-analysis of randomized controlled trials (RCTs) to compare their efficacy and safety in people with T2D. RCTs comparing both diets in participants with T2D were identified from MEDLINE, Embase, Cochrane Library, and manual search of bibliographies. Mean differences and relative risks with 95% CIs were pooled for measures of glycaemia, cardiometabolic parameters, and adverse events using the following time points: short-term (3 months), intermediate term (6 and 12 months) and long-term (24 months). Twenty-two RCTs comprising 1391 mostly obese participants with T2D were included. At 3 months, a LC vs. LF diet significantly reduced HbA1c levels, mean difference (95% CI) of −0.41% (−0.62, −0.20). LC diet significantly reduced body weight, BMI, fasting insulin and triglycerides and increased total cholesterol and HDL-C levels at the short-to-intermediate term, with a decrease in the requirement for antiglycaemic medications at intermediate-to-long term. There were no significant differences in other parameters and adverse events. Except for reducing HbA1c levels and adiposity parameters at short-to-intermediate terms, a LC diet appears to be equally effective as a LF diet in terms of control of cardiometabolic markers and the risk of adverse events in obese patients with T2D.