European Guidelines for Obesity Management in Adults with a Very Low-Calorie Ketogenic Diet: A Systematic Review and Meta-Analysis

BACKGROUND

The very low-calorie ketogenic diet (VLCKD) has been recently proposed as an appealing nutritional strategy for obesity management. The VLCKD is characterized by a low carbohydrate content (<50 g/day), 1-1.5 g of protein/kg of ideal body weight, 15-30 g of fat/day, and a daily intake of about 500-800 calories.

OBJECTIVES

The aim of the current document is to suggest a common protocol for VLCKD and to summarize the existing literature on its efficacy in weight management and weight-related comorbidities, as well as the possible side effects.

METHODS

This document has been prepared in adherence with Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Literature searches, study selection, methodology development, and quality appraisal were performed independently by 2 authors and the data were collated by means of a meta-analysis and narrative synthesis.

RESULTS

Of the 645 articles retrieved, 15 studies met the inclusion criteria and were reviewed, revealing 4 main findings. First, the VLCKD was shown to result in a significant weight loss in the short, intermediate, and long terms and improvement in body composition parameters as well as glycemic and lipid profiles. Second, when compared with other weight loss interventions of the same duration, the VLCKD showed a major effect on reduction of body weight, fat mass, waist circumference, total cholesterol and triglyceridemia as well as improved insulin resistance. Third, although the VLCKD also resulted in a significant reduction of glycemia, HbA1c, and LDL cholesterol, these changes were similar to those obtained with other weight loss interventions. Finally, the VLCKD can be considered a safe nutritional approach under a health professional's supervision since the most common side effects are usually clinically mild and easily to manage and recovery is often spontaneous.

CONCLUSIONS

The VLCKD can be recommended as an effective dietary treatment for individuals with obesity after considering potential contra-indications and keeping in mind that any dietary treatment has to be personalized. Prospero Registry: The assessment of the efficacy of VLCKD on body weight, body composition, glycemic and lipid parameters in overweight and obese subjects: a meta-analysis (CRD42020205189).

Alpha-lipoic acid (ALA) supplementation effect on glycemic and inflammatory biomarkers: A Systematic Review and meta- analysis

BACKGROUND & AIMS

Several randomized clinical trials (RCTs) have investigated the effect of Alpha - Lipoic Acid (ALA) supplementation on metabolic parameters, with conflicting results. Therefore, the present study assessed the effect of ALA on some glycemic and inflammatory parameters.

METHODS

A comprehensive literature search was conducted up from inception to July 2018 on PubMed, Scopus, Cochrane databases, Google Scholar, ProQuest, Web of Science, and Embase. From among eligible trials, 41 articles were selected for the meta-analysis. Two reviewers independently assessed the risk of bias and extracted data from the included studies. Meta-analyses using the random-effects model were performed to analyze the data.

RESULTS

Based on the Cochrane risk of bias tool, 19 articles had a good quality, 16 trials had a poor quality and 6 trials had a fair quality. The results demonstrated the significant effect of ALA on Fasting Blood Sugar (FBS) (weighted mean difference (WMD)) = -6.57, 95% confidence interval (CI: -11.91 to -1.23, P = 0.016), Hemoglobin A1c (HbA1c) (WMD = -0.35, 95% CI: -0.55 to -0.15, P = 0.004), Tumor Necrosis Factor Alpha (TNF-α) (WMD = -1.57, 95% CI: -2.29 to -0.85, P < 0.05), Interleukin 6 levels (IL-6) (WMD = -1.15, 95% CI: -1.58 to -0.72, P < 0.001), and C-reactive protein (CRP) (WMD = -0.31, 95% CI: -0.47 to -0.16, P > 0.001). No effect was detected for ALA on insulin and the homeostatic model assessment of insulin resistance (HOMA-IR).

CONCLUSIONS

These findings suggest that ALA is a viable supplement to improve some of the glycemic and inflammatory biomarkers.

Effects of the Mediterranean diet on cardiovascular risk factors in non-alcoholic fatty liver disease patients: A systematic review and meta-analysis

BACKGROUND & AIMS

We aimed to investigate the effect of the Mediterranean diet (MedDiet) on cardiovascular risk factors in patients with non-alcoholic fatty liver disease (NAFLD).

METHOD

A systematic search was performed in Scopus, Web of Science, Cochrane library and PubMed databases to find randomized controlled trials (RCTs) related to the effect of the MedDiet in patients with NAFLD, up to July, 2019. There was no language and time limitation. Meta-analyses were performed using both the random and fixed effects model where appropriate, and I2 index was used to evaluate the heterogeneity.

RESULTS

Primary search yielded 467 publications. Five RCTs were eligible. Our meta-analysis indicated that the MedDiet resulted in a significant decrease in serum levels of triglyceride and total cholesterol, and a decrease in body weight and HOMA-IR in comparison to a control diet, in NAFLD patients. Whereas, there were no significant improvement in the MedDiet group compared with the control group regarding other variables such as liver enzymes and blood pressure.

CONCLUSIONS

This meta-analysis indicated the advantageous effects of the MedDiet on some cardiovascular risks factors, as compared with a control diet. It seems that the MedDiet can be considered as an appropriate strategy to reduce cardiovascular risk factors in NAFLD patients.

Effects of pioglitazone therapy on blood parameters, weight and BMI: a meta-analysis

BACKGROUND

Type 2 diabetes mellitus (T2DM) is one of the most common diseases worldwide and insulin insufficiency and insulin resistance are two main metabolic issues connected with it. The dyslipidemia associated with insulin resistance and T2DM is characterized by higher triglycerides (TGs), higher very-low-density lipoprotein cholesterol and lower apo A1. Pioglitazone, a member of the thiazolidinedione class, with a proven antihyperglycemic effect, is known to positively influence insulin sensitivity and β-cell function and to have the potential to alter the lipid profile.

METHODS

The aim of our meta-analysis is to summarize and determine the influence of pioglitazone on the glycemic profile and lipoprotein metabolism as well as on weight and BMI in order to highlight the benefit of pioglitazone therapy in patients with T2DM. A comprehensive literature search was conducted through the electronic databases PubMed, MEDLINE, Scopus, PsyInfo, eLIBRARY.ru (from 2000 until February 2016) to identify studies that investigate the effect of pioglitazone on the glycemic and lipid profile and on the weight and BMI. We chose the random-effects method as the primary analysis. Forest plots depict estimated results from the studies included in the analysis and funnel plots are used to evaluate publication bias. Sensitivity analyses were performed in order to evaluate the degree of influence of the consequent elimination of each individual study on the final result.

RESULTS

Of the 1536 identified sources only 15 randomised trials were included in the meta-analysis. Pioglitazone treatment was associated with improvement in the glycemic profile. It reduced FPG levels by a mean of 1.1-2 mmol/l and HbA1c by a mean of 0.9-1.3%. Our results reaffirmed the hypothesis that pioglitazone has a positive influence on the lipid profile of T2DM patients with increase in TC and HDL, no significant changes in LDL and notable decrease in TGs. Results also showed that pioglitazone therapy led to increase in both weight and BMI (WMD 1.755, 95% CI 0.674 to 2.837 and 1.145, 95% CI 0.389 to 1.901 respectively).

CONCLUSION

Our results prove that the PPAR γ agonist pioglitazone has the potential to be beneficial to patients with T2DM.

Probiotics and Synbiotics Supplementation Improve Glycemic Control Parameters in Subjects with Prediabetes and Type 2 Diabetes Mellitus: A GRADE-assessed systematic review, meta-analysis, and meta-regression of randomized clinical trials

Probiotics and synbiotics have been proposed to exhibit an important role in glucose homeostasis and maintain the balance of the gut microbiota. However, clinical trials have shown mixed findings. Therefore, we conducted a systematic review and meta-analysis of all eligible randomized controlled trials (RCTs) examining the effects of probiotics and synbiotics intake on glycemic outcomes among individuals with prediabetes and type 2 diabetes mellitus (T2DM). The PubMed/Medline, Scopus, ISI Web of Science, and Cochrane library were searched up to March 2022 for published RCTs exploring the effectiveness of probiotics and synbiotics compared to control on glycemic outcomes. The random-effects model was applied in order to the estimation of 95% confidence interval (CI) and the weighted mean difference (WMD) for each endpoint. Meta-analysis of forty-six RCTs (3067 participants) showed that probiotics and synbiotics supplementation significantly reduced fasting plasma glucose (FPG) (weighted mean difference (WMD): -11.18mg/dl, 95% CI: -13.60, -8.75, p ˂0.001), fasting insulin serum level (WMD: -1.23 µIU/ml, 95% CI: -1.76, -0.71, p ˂0.001), hemoglobin A1c (HbA1c) (WMD: -0.35%, 95% CI: -0.44, -0.26, p˂0.001), and homeostatic model assessment of insulin resistance (HOMA-IR) (WMD: -0.87, 95% CI: -1.09, -0.65, p˂0.001). Additionally, probiotics and synbiotics intake resulted in an increase in values of quantitative insulin-sensitivity check index (QUICKI) (WMD: 0.01, 95% CI: 0.00, 0.01, p˂0.001). However, probiotics and synbiotics consumption did not change glucose values following oral glucose tolerance test (OGTT). Our findings suggest that probiotic and synbiotic intake has favorable effects on glycemic profile in patients with prediabetes and T2DM.

Associations between fruit and vegetables intake and abnormal glucose tolerance among women with prior gestational diabetes mellitus

PURPOSE

Women with prior gestational diabetes mellitus (GDM) are at higher risk of type 2 diabetes (T2D). The aim of this study was to investigate the association between fruit and vegetables (FV) intake and abnormal glucose tolerance (AGT) among women with prior GDM.

METHODS

A total of 281 women with prior GDM have been recruited a mean of 6 years after their pregnancy in this cohort study. FV intake was obtained with a validated food frequency questionnaire (FFQ). Anthropometric and glycemic components were measured during their clinical visit and women were stratified according to normal glucose tolerance (NGT) or AGT.

RESULTS

A cross-sectional analysis showed that a total of 155 women had NGT and 126 AGT. Women with AGT had significantly lower FV (6.5 ± 0.2) and vegetables servings (3.9 ± 0.2) and tended to have lower fruit servings (2.6 ± 0.2) than women with NGT (7.4 ± 0.2, 4.5 ± 0.2 and 3.0 ± 0.1, respectively) (p = 0.001, p = 0.04 and p = 0.10, respectively, adjusted for age and BMI). FV intake, per one serving increase, was associated with a reduced likelihood of having AGT [OR = 0.88 (0.81-0.97) after adjustment for age and BMI]. Vegetables or fruit intake tended to be associated with a reduced likelihood of having AGT [OR = 0.88 (0.78-1.00) and OR = 0.88 (0.76-1.02), respectively, after adjustment for age and BMI].

CONCLUSIONS

Higher intake of FV may be associated with a lower likelihood of AGT among women with prior GDM. Further studies are needed to confirm these results in this high-risk population.

Effects of l-arginine supplementation on glycemic profile: Evidence from a systematic review and meta-analysis of clinical trials

BACKGROUND

The effects of l-arginine supplementation on indices of glycemic control and the role of many factors influencing this intervention have been controversial in clinical trials.

OBJECTIVE

This meta-analysis was performed to assess the effects of l-arginine supplementation on indices of glycemic control, including fasting blood glucose (FBG), hemoglobin A1c (HbA1c), serum insulin and homeostatic model assessment of insulin resistance (HOMA-IR) levels in randomized controlled trials (RCTs).

SEARCH STRATEGY

This study conducted a systematic review of RCTs published in PubMed, Scopus, Web of Science, Cochrane Library and Embase, up to 5 May, 2018.

INCLUSION CRITERIA

Studies were included in this meta-analysis if they were RCTs with parallel design and reported sufficient data on participants before and after intervention, and outcomes of glycemic profile parameters in both the arginine supplementation and control groups.

DATA EXTRACTION AND ANALYSIS

The screening of titles and abstracts was performed independently by two reviewers. Selected articles were considered if they met the study's inclusion criteria. The quality of included studies was assessed by using the Cochrane Collaboration modified tool. From 710 articles retrieved in the initial search, only 10 trials were suitable for pooling the effects of arginine supplementation on serum glucose, insulin, HOMA-IR and HbA1c levels, with effect sizes of nine, eight, five and five, respectively.

RESULTS

Pooled random-effect analysis revealed that l-arginine supplementation could significantly decrease FBG level (weighted mean difference [WMD]: 3.35 mg/dL; 95% confidence interval [CI] = [-6.55, -0.16]; P = 0.04) and serum insulin level (WMD: -2.19 μIU/mL; 95% CI = [-3.70, -0.67]; P = 0.005). However, the effects of l-arginine supplementation on HOMA-IR and HbA1c were not significant. Results of subgroup analysis showed that supplementation with l-arginine could significantly decrease serum insulin levels when the dosage of l-arginine is > 6.5 g/d (WMD: -3.49 μIU/mL; 95% CI = [-5.59, -1.38]; P = 0.001), when the duration of supplementation is ≤ 12.8 weeks (WMD: -3.76; 95% CI = [-6.50, -0.98]; P = 0.008), when the participants are not diabetic patients (WMD: -2.54 μIU/mL; 95% CI = [-4.50, -0.50]; P = 0.01) and when the baseline serum level of insulin was > 20 μIU/mL (WMD: -3.98; 95% CI = [-6.31, -1.65]; P = 0.001).

CONCLUSION

Although the results of this study confirmed that supplementation with l-arginine could have significant effects on some glycemic profile indices of participants in clinical trials, the clinical importance of this reduction may not be meaningful.

Effects of probiotics supplementation on glycemic profile in adults with type 2 diabetes mellitus: A grade-assessed systematic review and dose-response meta-analysis of randomized controlled trials

BACKGROUND

Disturbed glycemia and the resulting type 2 diabetes (T2D) are significant health concerns. Various approaches have been examined to improve glycemic control in patients with T2D. Modification of gut microbiome via administering probiotics has been extensively studied. The present study aims to sum up the existing literature which investigated the effect of probiotics on glycemic indices in individuals with T2D in the format of randomized controlled trials (RCTs).

METHODS

Online medical databases (PubMed, Scopus, and Web of Science) were searched from inception to January 2024. Eligible studies were included using pre-defined inclusion and exclusion criteria. Outcome variables included fasting blood sugar (FBS), insulin, hemoglobin A1c (HbA1c), and homeostatic model of insulin resistance (HOMA-IR). Weighted mean differences (WMDs) were estimated. Subgroup and dose-response analyses were conducted. P-values <0.05 were considered as statistically significant.

RESULTS

Out of 5636 records retrieved by the initial search, thirty-two RCTs were included in the final analyses. Supplementation with probiotics was observed to significantly improve indices of glycemic control; including FBS (WMD: -13.27 mg/dl; 95 % CI: -18.31, -8.22), HbA1c (WMD: -0.44 %; 95 % CI: -0.59, -0.28), insulin (WMD: -1.33 μIU/ml; 95 % CI: -2.57, -0.08), and HOMA-IR (WMD: -0.95; 95 % CI: -1.71, -0.18). Dose-response analysis revealed that increased duration of intervention results in a larger reduction only in FBS.

CONCLUSION

Supplementation with probiotics seems to improve indices of glycemic control. Nonetheless, taken into account the notable heterogeneity (with regard to dosage, duration, and the species/strains used) between the included studies and low quality of evidence, caution must be considered, especially when long-term clinical implications are intended.

Effects of curcumin/turmeric supplementation on glycemic indices in adults: A grade-assessed systematic review and dose-response meta-analysis of randomized controlled trials

INTRODUCTION

Glycemic control is of utmost importance both as a preventive measure in individuals at risk of diabetes and in the management of patients with disturbed glycemia. Turmeric/curcumin has been extensively studied in this field. In the present systematic review and meta-analysis, we aimed at investigating the impact of turmeric/curcumin supplementation on glycemic control.

METHODS

Major online databases (PubMed, Scopus, Web of Science, Cochrane Library and Google Scholar) were systematically searched from inception up to October 2022. Relevant randomized controlled trials (RCTs) meeting our eligible criteria were included. Weighted mean differences (WMDs) with confidence intervals (CIs) were expressed using a random-effect model. Subgroup analyses were conducted to find the sources of heterogeneities. To detect risk of bias in the included studies, we used the Cochrane risk-of-bias tool. The registration number was CRD42022374874.

RESULTS

Out of 4182 articles retrieved from the initial search, 59 RCTs were included. Our findings suggested that turmeric/curcumin supplementation was significantly effective in improving fasting blood sugar (WMD: 4.60 mg/dl; 95% CI: 5.55, -3.66), fasting insulin levels (WMD: 0.87 μIU/ml; 95% CI: 1.46, -0.27), hemoglobin A1c (HbA1c) (WMD: 0.32%; 95% CI: 0.45, -0.19), and homeostatic model assessment of insulin resistance (HOMA-IR) (WMD: 0.33; 95% CI: 0.43, -0.22).

CONCLUSION

Our results indicate that turmeric/curcumin supplementation can be considered as a complementary method in the management of disturbed glycemia.

The effects of conjugated linoleic acid supplementation on glycemic control, adipokines, cytokines, malondialdehyde and liver function enzymes in patients at risk of cardiovascular disease: a GRADE-assessed systematic review and dose-response meta-analysis

BACKGROUND

The present systematic review and meta-analysis sought to evaluate the effects of conjugated linoleic acid (CLA) supplementation on glycemic control, adipokines, cytokines, malondialdehyde (MDA) and liver function enzymes in patients at risk of cardiovascular disease.

METHODS

Relevant studies were obtained by searching the PubMed, SCOPUS and Web of Science databases (from inception to January 2023). Weighted mean differences (WMD) and 95% confidence intervals (CIs) were pooled using a random-effects model. Heterogeneity, sensitivity analysis, and publication bias were reported using standard methods.

RESULTS

A pooled analysis of 13 randomized controlled trials (RCTs) revealed that CLA supplementation led to a significant increment in fasting blood glucose (FBG) (WMD: 4.49 mg/dL; 95%CI: 2.39 to 6.59; P < 0.001), and aspartate aminotransferase (AST) (WMD: 2.54 IU/L; 95%CI: 0.06 to 5.01; P = 0.044). Moreover, CLA supplementation decreased leptin (WMD: -1.69 ng/ml; 95% CI: -1.80 to -1.58; P < 0.001), and interleukin 6 (IL-6) (WMD: -0.44 pg/ml; 95%CI: -0.86 to -0.02; P = 0.037). However, there was no effect on hemoglobin A1c (HbA1c), homeostatic model assessment for insulin resistance (HOMA-IR), C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), and alanine aminotransferase (ALT) adiponectin compared to the control group.

CONCLUSION

Our findings showed the overall favorable effect of CLA supplementation on the adipokines and cytokines including serum IL-6, and leptin, while increasing FBG and AST. It should be noted that the mentioned metabolic effects of CLA consumption were small and may not reach clinical importance.

PROSPERO REGISTERATION COD

CRD42023426374.

Current perspectives in obesity management: unraveling the impact of different therapy approach in real life obesity care

BACKGROUND

The challenge of addressing obesity persists in healthcare, necessitating nuanced approaches and personalized strategies. This study aims to evaluate the effects of diverse therapeutic interventions on anthropometric and biochemical parameters in individuals with overweight and obesity within a real-world clinical context.

METHODS

A retrospective analysis was conducted on 192 patients (141 females, 51 males) aged 18 to 75, with a BMI ranging from 25 to 30 (14.1%) and BMI ≥ 30 (85.9%), observed over a 12-month period at our Endocrinology Unit. Treatment cohorts comprised individuals following different regimens: Mediterranean Diet (MD), with an approximate daily intake of 1500 kcal for women and 1800 kcal for men (71% patients); Ketogenic Diet (KD), utilizing the VLCKD protocol characterized by a highly hypocaloric dietary regimen < 800 kcal/day (14% patients); metformin, administered using the oral formulation (5% patients); pharmacological intervention with GLP1-RA administered via subcutaneous injection with incremental dosage (10% patients). Supply constraints limited the efficacy of Liraglutide, whereas Semaglutide was excluded from comparisons due to its unavailability for obesity without diabetes. Blood tests were conducted to assess lipid profile, glycemic profile, and anthropometric parameters, including BMI, waist circumference, and waist-to-height ratio.

RESULTS

Significant BMI changes were observed from baseline to 6 months across MD, KD, and Liraglutide groups (p < 0.05). KD exhibited notable reductions in waist circumference and waist-to-height ratio within the initial quarter (p < 0.05), with a significant triglyceride decrease after 6 months (p < 0.05), indicating its efficacy over MD. Liraglutide demonstrated a substantial reduction in HbA1c levels in the first quarter (p < 0.05). During the first three months, the ANOVA test on fasting blood glucose showed a statistically significant impact of the time variable (p < 0.05) rather than the specific treatments themselves (Liraglutide and KD), suggesting that adherence during the early stages of therapy may be more critical than treatment choice.

CONCLUSIONS

Positive outcomes from targeted interventions, whether pharmacological or dietary should encourage the exploration of innovative, long-term strategies that include personalized treatment alternation. The absence of standardized protocols underscores the importance of careful and tailored planning in managing obesity as a chronic condition.

Effect of switching from twice-daily basal insulin to once-daily insulin glargine 300 U/mL (Gla-300) in Brazilian people with type 1 diabetes

BACKGROUND

Low adherence to the number of insulin injections and glycemic variability are among the challenges of insulin therapy in type 1 diabetes (T1D). The TOP1 study investigated the effect of switching from twice-daily (BID) basal insulin to once daily (OD) insulin glargine 300 U/mL (Gla-300) on glycemic control and quality of life.

METHODS

In this 28-week, phase 4 trial, people with T1D aged ≥ 18 years, who were treated with BID basal insulin in combination with prandial rapid-acting insulin for at least 1 year, and had HbA1c between 7.5% and 10.0%, were switched to Gla-300 OD as basal insulin. The present study aimed to evaluate the impact of this change on HbA1c, glycemic profile, treatment satisfaction and safety. The change in HbA1c from baseline to Week 24 was the primary endpoint.

RESULTS

One hundred and twenty-three people with T1D (mean age 37 ± 11 years; 54.5% female) were studied. The disease duration was 20.0 ± 9.8 years, baseline HbA1c and fasting plasma glucose (FPG) were 8.6 ± 0.7% and 201 ± 80.3 mg/dL, respectively. After switching from BID to OD insulin regimen, no significant change in HbA1c was observed from baseline to Week 24 (p = 0.873). There were significant reductions in fasting self-monitoring blood glucose (SMBG) from baseline to Week 24 (175 ± 42 vs. 156 ± 38 mg/dL; p < 0.0001), and in glycemic profile (8-point SMBG) at several time points. There was a significant decrease in the proportion of patients with at least one hypoglycemic event (p = 0.025), in numbers of hypoglycemic events per patient-years of any type (p = 0.036), symptomatic (p = 0.007), and confirmed ≤ 70 mg/dL events (p = 0.049) from run-in to the last 4 weeks on treatment. There were significant improvements in treatment satisfaction (p < 0.0001), perceived hyperglycemia (p < 0.0001) scores and satisfaction with the number of injections between post-run-in and Week 24, and a significant decrease in fear of hypoglycemia.

CONCLUSIONS

Switch from BID basal insulin to OD Gla-300 as part of basal bolus therapy in T1D resulted in similar glycemic control as measured by HbA1c, but provided significant improvements in SMBG, daily glucose profile, a lower incidence of hypoglycemia and increased patient satisfaction.

TRIAL REGISTRATION

NCT03406000.

The effects of vitamin C supplementation on glycemic control in patients with type 2 diabetes: A systematic review and meta-analysis

BACKGROUND AND AIM

It has been suggested that taking vitamin C supplements may improve glycemic control in patients with type 2 diabetes mellitus (T2DM). However, there has not been a thorough evaluation of the actual impact or certainty of the findings. This systematic review and meta-analysis was conducted to determine the effect of vitamin C supplementation on glycemic profile in T2DM patients.

METHODS

A systematic search was performed across online databases including Scopus, Web of Science, and PubMed/Medline to identify relevant randomized controlled trials (RCTs) published until July 2022. A random-effects model was applied for the meta-analysis.

RESULTS

The present meta-analysis included a total of 22 RCTs with 1447 patients diagnosed with T2DM.A pooled analysis revealed a significant decrease in levels of serum hemoglobin A1c (HbA1c), fasting insulin, and fasting blood glucose (FBG) in vitamin C-treated T2DM patients compared with their untreated counterparts. The dose-response evaluation displayed a substantial linear association between the intervention duration and changes in serum HbA1c levels. However, the analysis did not demonstrate any significant effect of vitamin C on serum values of homeostasis model assessment of insulin resistance(HOMA-IR) in diabetic patients. Subgroup analyses indicated that high-dose vitamin C administration (≥1000 mg/d) considerably decreased serum HOMA-IR levels.

CONCLUSION

These findings suggest that long-term (≥12 weeks) and high-dose vitamin C supplementation (≥1000 mg/d) may ameliorate glycemic profile in T2DM patients. However, additional high-quality RCTs are necessary to validate these results.