Best Supplements for Reduced Hemoglobin A1c
Ranked by research evidence. Compare 47 supplements across 61 papers from the biomedical literature, with effect direction, evidence strength, and dose range for each.
Top picks by evidence
- Moderate evidence3 studies
Across 3 studies, all reported beneficial effects on reducing HbA1c, with predominant effect size moderate. One 12-month RCT in adults with type 2 diabetes used 1500 mg/day turmeric (curcumin) and found a small beneficial effect (HbA1c 6.10% vs 6.40%, p<0.05). A meta-analysis of 63 RCTs reported a moderate reduction (MD = -0.31%, 95% CI -0.57 to -0.05). Effects were observed in clinical populations with type 2 diabetes or hyperglycemia.
- Moderate evidence3 studies
Across 3 meta-analyses, 2 reported beneficial moderate-sized effects of black cumin supplementation on reducing hemoglobin A1c in people with type 2 diabetes, while 1 found a neutral small effect. The evidence is preliminary due to the small number of studies and limited reporting of dose and duration; the only reported median study duration was 7 days, which is insufficient for HbA1c changes.
- Very low evidence3 studies
Across 3 studies, 2 reported beneficial effects of cinnamon on reducing Hemoglobin A1c, while 1 found no significant effect. The predominant effect size was small, with one meta-analysis reporting a 0.10% reduction (small) and another showing a moderate effect (SMD -0.71). The evidence base is small, and the most-studied population is adults with type 2 diabetes, though doses and durations were not consistently reported.
- ModerateTurmericAcross 3 studies, all reported beneficial effects on reducing HbA1c, with predominant effect size moderate. One 12-month RCT in adults with type 2 diabetes used 1500 mg/day turmeric (curcumin) and found a small beneficial effect (HbA1c 6.10% vs 6.40%, p<0.05). A meta-analysis of 63 RCTs reported a moderate reduction (MD = -0.31%, 95% CI -0.57 to -0.05). Effects were observed in clinical populations with type 2 diabetes or hyperglycemia.3 beneficial3 studies
- ModerateBlack CuminAcross 3 meta-analyses, 2 reported beneficial moderate-sized effects of black cumin supplementation on reducing hemoglobin A1c in people with type 2 diabetes, while 1 found a neutral small effect. The evidence is preliminary due to the small number of studies and limited reporting of dose and duration; the only reported median study duration was 7 days, which is insufficient for HbA1c changes.2 beneficial1 neutral3 studies
- Very lowCinnamonAcross 3 studies, 2 reported beneficial effects of cinnamon on reducing Hemoglobin A1c, while 1 found no significant effect. The predominant effect size was small, with one meta-analysis reporting a 0.10% reduction (small) and another showing a moderate effect (SMD -0.71). The evidence base is small, and the most-studied population is adults with type 2 diabetes, though doses and durations were not consistently reported.2 beneficial1 neutral3 studies