The effect of flaxseed supplementation on anthropometric indices, blood pressure, and lipid profile in diabetic patients: A GRADE-assessed systematic review and meta-analysis of randomized controlled trials.
- 2025-05
- Diabetes & metabolic syndrome 19(5)
- Vali Musazadeh
- Shokufeh Nezamoleslami
- Amir Hossein Faghfouri
- Farzad Shidfar
- Naheed Aryaeian
- PubMed: 40499336
- DOI: 10.1016/j.dsx.2025.103241
Study Design
- Type
- Meta-Analysis
- Sample size
- n = 1,136
- Population
- 1136 participants with type 2 diabetes
- Methods
- Meta-analysis, random-effects model, standardized mean differences
Background and aims
Numerous clinical studies have suggested that flaxseed supplementation may be effective in diabetic patients, but the findings are controversial. Therefore, this study aimed to examine the effects of flaxseed on blood pressure, anthropometry, and lipid profile parameters in diabetic patients.Methods
PubMed, Cochrane Library, Web of Science, Scopus, Embase databases, and Google Scholar were searched until June 2024. A random-effects model was utilized to analyze standardized mean differences (SMDs).Results
Meta-analysis of 16 trials with 1136 participants indicated significant improvements in weight (SMD: 0.81; 95 % CI: 1.54 to -0.09, p = 0.028; I2 = 88.7 %, p < 0.001), waist circumference (SMD: 1.54; 95 % CI: 2.77 to -0.31, p = 0.002; I2 = 85.3 %, p < 0.001), and triglyceride (SMD: 0.56; 95 % CI: 1.02 to -0.10, p = 0.016; I2 = 87.4 %, p < 0.001), but not BMI (SMD: 0.63; 95 % CI: 1.28 to 0.02, p = 0.058; I2 = 87.9 %, p = 0.005), systolic blood pressure (SMD: 0.50; 95 % CI: 1.25, 0.25, p = 0.193; I2 = 87.6 %, p < 0.001), diastolic blood pressure (SMD: 0.74; 95 % CI: 1.51, 0.03, p = 0.060; I2 = 88.1 %, p < 0.001), total cholesterol (SMD: 0.43; 95 % CI: 0.99 to 0.12, p = 0.128; I2 = 93.6 %, p < 0.001), low-density lipoprotein cholesterol (SMD: 0.09; 95 % CI: 0.87 to 0.70, p = 0.830; I2 = 96.3 %, p < 0.001), and high-density lipoprotein cholesterol (SMD: 0.08; 95 % CI: 0.30 to 0.46, p = 0.673; I2 = 87.2 %, p < 0.001).Conclusion
Flaxseed supplementation effectively reduces anthropometric indices and triglyceride levels in individuals with type 2 diabetes but does not suggest any benefit on blood pressure and other lipid profile parameters. Therefore, conducting more extensive, well-designed trials to validate these findings is crucial.Research Insights
total cholesterol (SMD: 0.43; 95% CI: 0.99 to 0.12, p = 0.128)
- Effect
- Neutral
- Effect size
- Small
not BMI (SMD: 0.63; 95% CI: 1.28 to 0.02, p = 0.058)
- Effect
- Neutral
- Effect size
- Small
significant improvements in weight (SMD: 0.81; 95% CI: 1.54 to -0.09, p = 0.028)
- Effect
- Beneficial
- Effect size
- Large
diastolic blood pressure (SMD: 0.74; 95% CI: 1.51, 0.03, p = 0.060)
- Effect
- Neutral
- Effect size
- Small
high-density lipoprotein cholesterol (SMD: 0.08; 95% CI: 0.30 to 0.46, p = 0.673)
- Effect
- Neutral
- Effect size
- Small
low-density lipoprotein cholesterol (SMD: 0.09; 95% CI: 0.87 to 0.70, p = 0.830)
- Effect
- Neutral
- Effect size
- Small
systolic blood pressure (SMD: 0.50; 95% CI: 1.25, 0.25, p = 0.193)
- Effect
- Neutral
- Effect size
- Small
significant improvements in triglyceride (SMD: 0.56; 95% CI: 1.02 to -0.10, p = 0.016)
- Effect
- Beneficial
- Effect size
- Moderate
significant improvements in waist circumference (SMD: 1.54; 95% CI: 2.77 to -0.31, p = 0.002)
- Effect
- Beneficial
- Effect size
- Large