Effect of vitamin E intake on glycemic control and insulin resistance in diabetic patients: an updated systematic review and meta-analysis of randomized controlled trials

source extracted confidence: high 2026-04-09
#adult #humans #insulin-resistance #blood-glucose #glycated-hemoglobin

Effect of vitamin E intake on glycemic control and insulin resistance in diabetic patients: an updated systematic review and meta-analysis of randomized controlled trials

Asbaghi et al., 2023 | Nutr J | Meta Analysis

Citation

Asbaghi Omid, Nazarian Behzad, ... Sadeghi Omid. Effect of vitamin E intake on glycemic control and insulin resistance in diabetic patients: an updated systematic review and meta-analysis of randomized controlled trials. Nutr J. 2023-Feb-17;22(1):10. doi:10.1186/s12937-023-00840-1

Abstract

Since a 2014 meta-analysis, several randomized controlled trials (RCTs) evaluating the effect of vitamin E intake on glycemic indices and insulin resistance in adults with diabetes have reached inconsistent conclusions. Therefore, we updated the previous meta-analysis to summarize the current evidence in this regard. Online databases including PubMed, Scopus, ISI Web of Science, and Google Scholar were searched to identify relevant studies published up to September 30, 2021, using relevant keywords. Random-effects models were used to obtain overall mean difference (MD) comparing vitamin E intake with a control group. In total, 38 RCTs with a total sample size of 2171 diabetic patients (1110 in vitamin E groups and 1061 in control groups) were included. Combining the results from 28 RCTs on fasting blood glucose, 32 RCTs on HbA1c, 13 RCTs on fasting insulin, and 9 studies on homeostatic model assessment for insulin resistance (HOMA-IR) showed a summary MD of -3.35 mg/dL (95% CI: -8.10 to 1.40, P = 0.16), -0.21% (95% CI: -0.33 to -0.09, P = 0.001), -1.05 µIU/mL (95% CI: -1.53 to -0.58, P < 0.001), and -0.44 (95% CI: -0.82 to -0.05, P = 0.02), respectively. This indicates a significant lowering effect of vitamin E on HbA1c, fasting insulin and HOMA-IR, while no significant effect on fasting blood glucose in diabetic patients. However, in subgroup analyses, we found that vitamin E intake significantly reduced fasting blood glucose in studies with an intervention duration of < 10 weeks. In conclusion, vitamin E intake has a beneficial role in improving HbA1c and insulin resistance in a population with diabetes. Moreover, short-term interventions with vitamin E have resulted in lower fasting blood glucose in these patients. This meta-analysis was registered in PROSPERO with code CRD42022343118.

Key Findings

This meta-analysis was registered in PROSPERO with code CRD42022343118.

Outcomes Measured

  • Requires manual extraction

Population

Field Value
Population See abstract
Sample Size 38
Age Range See abstract
Condition diabetes

MeSH Terms

  • Adult
  • Humans
  • Insulin Resistance
  • Blood Glucose
  • Glycated Hemoglobin
  • Glycemic Control
  • Randomized Controlled Trials as Topic
  • Diabetes Mellitus
  • Insulin
  • Diabetes Mellitus, Type 2
  • Dietary Supplements

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Meta-Analysis, Systematic Review, Journal Article, Research Support, Non-U.S. Gov't
  • Vertical: vitamin-e

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09