Research synthesisLow evidenceMixed effect size4 studies · 2 beneficial · 2 neutral · 0 harmful
Across 4 studies on flaxseed for reducing low-density lipoprotein (LDL) levels, 2 reported beneficial effects and 2 reported neutral results, yielding a mixed evidence base. The beneficial effects were small to moderate in magnitude, with one meta-analysis showing a significant reduction in postmenopausal women (WMD = -0.15 mmol/L, p = 0.0067), while larger meta-analyses in patients with type 2 diabetes and coronary artery disease found no significant effect. Doses of ≥30 g/day over at least 12 weeks were associated with benefit in one review, but overall the most-studied dose range is not consistently reported.
- Studied populations: postmenopausal women
Caveats: Evidence base is small (only 4 studies) — conclusions should be considered preliminary. Many of the included studies did not reach statistical significance — effect may be smaller than the predominant direction suggests. The two neutral studies were meta-analyses with moderate to high evidence scores, while the two beneficial studies included one with a lower evidence score, creating uncertainty about the reliability of the positive findings.
Generated Jun 10, 2026