The effect of Nigella sativa supplementation on glycemic status in adults: An updated systematic review and meta-analysis of randomized controlled trials.

2024-10
Prostaglandins & other lipid mediators 174
- Shabnam Shirvani
- Maryam Falahatzadeh
- Elham Oveili
- Mehrdad Jamali
- Pedram Pam
- Maryam Parang
- Mehrnaz Shakarami

PubMed: 39181437
DOI: 10.1016/j.prostaglandins.2024.106885

Study Design

Type: Meta-Analysis
Sample size: n = 30
Population: adults
Methods: systematic literature search up to December 2023 in PubMed, Scopus, and Web of Science, to identify eligible RCTs; random effects models based on heterogeneity tests; pooled data as weighted mean differences with 95% CI

This systematic review and meta-analysis of randomized controlled trials (RCTs) sought to evaluate the effects of Nigella sativa (N. sativa) consumption on glycemic index in adults. A systematic literature search up to December 2023 was completed in PubMed, Scopus, and Web of Science, to identify eligible RCTs. Random effects models were assessed based on the heterogeneity tests, and pooled data were determined as weighted mean differences with a 95 % confidence interval. Finally, a total of 30 studies were found to be eligible for this meta-analysis. The pooled results using random effects model indicated that N. sativa supplementation significantly reduced FBS (SMD: -1.71; 95 % CI: -2.11, -1.31, p <0.001; I²= 92.7 %, p-heterogeneity <0.001) and HA1c levels (SMD: -2.16; 95 % CI: -3.04, -1.29, p <0.001; I²= 95.7 %, p-heterogeneity <0.001) but not effect on insulin (SMD = 0.48; 95 % CI: -0.53, 1.48, P = 0.353; I²= 96.1 %, p-heterogeneity <0.001), and HOMA-IR (SMD: -0.56; 95 % CI: -1.47, 0.35, p=0.229; I²= 95.0 %, p-heterogeneity <0.001).Overall, the evidence supports the consumption of N. sativa to reduce FBS and HA1c levels. Additional research, featuring extended durations and robust study designs, is necessary to determine the ideal dosage and duration of N. sativa supplementation for achieving a positive impact on glycemic markers.

Research Insights

Black Cumin→Improved Insulin Levels
but not effect on insulin (SMD = 0.48; 95% CI: -0.53, 1.48, P = 0.353; I²= 96.1%, p-heterogeneity <0.001)
Effect
Neutral
Effect size
Small
Black Cumin→Reduced Fasting Blood Glucose Levels
N. sativa supplementation significantly reduced FBS (SMD: -1.71; 95% CI: -2.11, -1.31, p <0.001; I²= 92.7%, p-heterogeneity <0.001)
Effect
Beneficial
Effect size
Large
Black Cumin→Reduced HOMA-IR
and HOMA-IR (SMD: -0.56; 95% CI: -1.47, 0.35, p=0.229; I²= 95.0%, p-heterogeneity <0.001)
Effect
Neutral
Effect size
Small
Black Cumin→Reduced Hemoglobin A1c
N. sativa supplementation significantly reduced ... HA1c levels (SMD: -2.16; 95% CI: -3.04, -1.29, p <0.001; I²= 95.7%, p-heterogeneity <0.001)
Effect
Beneficial
Effect size
Large