Impact of flaxseed supplementation on lipid profile and liver enzymes in patients with non-alcoholic fatty liver disease: Systematic review and meta-analysis of randomized controlled trials

Since the effects of flaxseed supplementation on lipid profile and liver enzymes are still controversial, a meta-analysis of randomized controlled trials was conducted in the present study to assess the effect of flaxseed supplementation on lipid profile and liver enzymes. The study was designed, conducted, and reported according to the guidelines of the 2020 preferred reporting items for systematic reviews and meta-analysis (PRISMA) statement. A systematic and comprehensive search was performed in several databases from inception up to January 10, 2024. The meta-analysis on the impact of flaxseed supplementation on lipid profile and liver enzymes indicates that the overall effect of flaxseed supplementation on triglycerides, combining different doses, revealed a significant reduction with a WMD of − 230.72 (-53.95, − 27.49) and a P-value of 0.010. High-density lipoprotein (HDL) demonstrated a positive effect, with an overall WMD of 1.82 (0.27, 3.38) and a P-value of 0.021, indicating an increase in HDL levels. The liver enzymes AST and ALT displayed reductions in their levels, with overall WMDs of − 21.18 (-2.95, 0.59) and − 24.83 (-8.74, − 20.91), respectively. Subgroup analysis based on dosage revealed more pronounced reductions in ALT levels for doses below 2000 mg/day. Findings from this study suggest that a flaxseed supplement might be beneficial to modulate the blood lipid profile and liver enzymes.