The effects of vitamin C supplementation on glycemic control in patients with type 2 diabetes: A systematic review and meta-analysis
The effects of vitamin C supplementation on glycemic control in patients with type 2 diabetes: A systematic review and meta-analysis
Nosratabadi et al., 2023 | Diabetes Metab Syndr | Meta Analysis
Citation
Nosratabadi Saeed, Ashtary-Larky Damoon, ... Asbaghi Omid. The effects of vitamin C supplementation on glycemic control in patients with type 2 diabetes: A systematic review and meta-analysis. Diabetes Metab Syndr. 2023-Aug;17(8):102824. doi:10.1016/j.dsx.2023.102824
Abstract
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.
Key Findings
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
Outcomes Measured
- Requires manual extraction
Population
| Field | Value |
|---|---|
| Population | type 2 diabetes mellitus |
| Sample Size | 1447 |
| Age Range | See abstract |
| Condition | diabetes |
MeSH Terms
- Humans
- Glycated Hemoglobin
- Blood Glucose
- Vitamin D
- Glycemic Control
- Diabetes Mellitus, Type 2
- Vitamins
- Dietary Supplements
- Ascorbic Acid
Evidence Classification
- Level: Meta Analysis
- Publication Types: Meta-Analysis, Systematic Review, Journal Article
- Vertical: vitamin-c
Provenance
- PMID: 37523928
- DOI: 10.1016/j.dsx.2023.102824
- PMCID: Not in PMC
- Verified: 2026-04-09 via PubMed E-utilities API
Source extracted via PubMed E-utilities API on 2026-04-09