Turmeric and Reduced Hemoglobin A1c

Research synthesisModerate evidenceModerate effect3 studies · 3 beneficial · 0 neutral · 0 harmful

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.

Studied populations: adults with type 2 diabetes or hyperglycemia

Caveats: Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). Evidence base is small (only 3 studies) — conclusions should be considered preliminary.

Generated May 16, 2026

Doses used in studies

mg/day: 1,500 (median 1,500, IQR 1,500–1,500) — 1 study

Time to effect

Median: 12.2 months · IQR 12.2 months–12.2 months · Range 12.2 months–12.2 months — Reported in 1 of 3 studies

Safety in these studies

blood pressureNo significant difference
No significant effects were observed on total cholesterol, blood pressure, body mass index, blood urea nitrogen, or creatinine levels.
from: Antidiabetic and Metabolic Effects of Turmeric (Curcuma Longa) in Patients with Type 2 Dia
blood urea nitrogenNo significant difference
No significant effects were observed on total cholesterol, blood pressure, body mass index, blood urea nitrogen, or creatinine levels.
from: Antidiabetic and Metabolic Effects of Turmeric (Curcuma Longa) in Patients with Type 2 Dia
body mass indexNo significant difference
No significant effects were observed on total cholesterol, blood pressure, body mass index, blood urea nitrogen, or creatinine levels.
from: Antidiabetic and Metabolic Effects of Turmeric (Curcuma Longa) in Patients with Type 2 Dia
creatinineNo significant difference
No significant effects were observed on total cholesterol, blood pressure, body mass index, blood urea nitrogen, or creatinine levels.
from: Antidiabetic and Metabolic Effects of Turmeric (Curcuma Longa) in Patients with Type 2 Dia
Overall tolerabilityReported
No significant effects were observed on total cholesterol, blood pressure, body mass index, blood urea nitrogen, or creatinine levels.
from: Antidiabetic and Metabolic Effects of Turmeric (Curcuma Longa) in Patients with Type 2 Dia
Overall tolerabilityReported
No explicit adverse events or safety findings are reported in the abstract.
from: Clinical Potential of Curcuma longa Linn. as Nutraceutical/Dietary Supplement for Metaboli

3 of 3 papers

Curcumin Supplementation Reduces Inflammation, Neutrophil-to-Lymphocyte Ratio (NLR), and Antioxidant Status in Obese Patients with Type 2 Diabetes: A Randomized Controlled Trial.
- 2026-04-27
- RCT · n = 114
- International journal of molecular sciences 27(9)
- - Metha Yaikwawong
  - Khanittha Kamdee
  - Somlak Chuengsamarn
- PubMed: 42123439
- DOI: 10.3390/ijms27093854
8 Insights on
- Reduced Hemoglobin A1c
- High evidence
- Large Human Trial
- Rigorous Journal
- Clinical
HbA1c (6.10% vs. 6.40%; p < 0.05)
Effect
Beneficial
Effect size
Small
Significant
Yes
Dose
1500 mg/day
Antidiabetic and Metabolic Effects of Turmeric (Curcuma Longa) in Patients with Type 2 Diabetes Mellitus or Hyperglycemia - A Systematic Meta-Review and Meta-Analysis.
- 2025-10-17
- Meta-Analysis
- Journal of Nepal Health Research Council 23(02)
- - Kapil Amgain
  - Richa Shah
  - Siti Munirah Md Noh
  - Shamsher Shrestha
  - Bijay Aryal
  - Lok Raj Joshi
  - Sujana Neupane
  - Shamima Abdul Rahman
- PubMed: 41319069
- DOI: 10.33314/jnhrc.v23i02.4708
10 Insights on
- Reduced Hemoglobin A1c
- High evidence
- Clinical
The pooled analysis revealed that curcumin significantly reduced ... HbA1c (MD = - 0.31%; 95% CI: - 0.57, - 0.05)
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Clinical Potential of Curcuma longa Linn. as Nutraceutical/Dietary Supplement for Metabolic Syndrome: Systematic Review and Meta-Analysis of Randomized Controlled Trials.
- 2025-12-24
- Review
- Foods (Basel, Switzerland) 15(1)
- - Samuel Abiodun Kehinde
  - Zahid Naeem Qaisrani
  - Rinrada Pattanayaiying
  - Bo Bo Lay
  - Khin Yadanar Phyo
  - Wai Phyo Lin
  - Myat Mon San
  - Nurulhusna Awaeloh
  - Sasithon Aunsorn
  - Ran Kitkangplu
  - Sasitorn Chusri
- PubMed: 41517125
- DOI: 10.3390/foods15010060
9 Insights on
- Reduced Hemoglobin A1c
- Low evidence
- Clinical
HbA1c (SMD = -0.41, 95% CI -0.60 to -0.23) in T2DM
Effect
Beneficial
Effect size
Moderate
Significant
Yes

Turmeric and Reduced Hemoglobin A1c

Curcumin Supplementation Reduces Inflammation, Neutrophil-to-Lymphocyte Ratio (NLR), and Antioxidant Status in Obese Patients with Type 2 Diabetes: A Randomized Controlled Trial.

Antidiabetic and Metabolic Effects of Turmeric (Curcuma Longa) in Patients with Type 2 Diabetes Mellitus or Hyperglycemia - A Systematic Meta-Review and Meta-Analysis.

Clinical Potential of Curcuma longa Linn. as Nutraceutical/Dietary Supplement for Metabolic Syndrome: Systematic Review and Meta-Analysis of Randomized Controlled Trials.