Effects of Omega-3 Fatty Acids Supplementation on Serum Lipid Profile and Blood Pressure in Patients with Metabolic Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Foods
Q1
Feb 2023
Citations:34
Influential Citations:1
Systematic Reviews / Meta-Analyses
82
S2 IconPDF Icon

Enhanced Details

Methods
Eight randomized controlled trials (seven parallel-group, one crossover) including 387 adults with metabolic syndrome; mean age 45.54 years; durations ranged from 49 to 168 days; populations included mixed gender with some trials in postmenopausal women.
Intervention
Regimens across eight randomized trials included: Flaxseed oil 25 mL daily for 7 weeks (control: sunflower seed oil); Fish oil 1 g daily (EPA 180 mg, DHA 120 mg) for 6 months; Fish oil 3 g daily (EPA 1800 mg, DHA 1200 mg) for 90 days; Fish oil 3 g daily (EPA 1800 mg, DHA 1200 mg) for 90 days; Omega-3 PUFA supplements 2 g daily (composition not fully specified) for 12 weeks; Daily fish oil capsules (dosage not specified) for 8 weeks with corn oil as control; Omega-3 supplementation totaling 900 mg daily (180 mg EPA, 120 mg DHA) for 6 months; Omega-3 supplement delivering 720 mg EPA daily with 100 mg vitamin E for 12 weeks.
Results
Omega-3 fatty acid supplementation in metabolic syndrome did not significantly change total cholesterol (SMD -0.02; 95% CI -0.22 to 0.18; I2 23.7%), LDL-C (SMD 0.18; 95% CI -0.18 to 0.53; I2 54.9%), or HDL-C (SMD 0.02; 95% CI -0.21 to 0.25; I2 0%). It significantly reduced triglycerides (SMD -0.39; 95% CI -0.59 to -0.18; I2 17.2%), systolic blood pressure (SMD -0.54; 95% CI -0.86 to -0.22; I2 48.6%), and diastolic blood pressure (SMD -0.56; 95% CI -0.79 to -0.33; I2 14.0%). Sensitivity analyses supported robustness; triglyceride reduction was more pronounced in studies lasting longer than 12 weeks. The analysis suggests n-3 PUFA supplementation may serve as a potential dietary option to improve triglycerides and blood pressure in metabolic syndrome, though effects on other lipids are less clear and differential EPA vs DHA effects were not resolved.
Limitations
Limitations include a small number of trials (n=8) and participants (n=387) with heterogeneous regimens and doses; several trials had high risk of bias for blinding; potential publication bias could not be fully assessed due to the limited number of studies.

Abstract

The purpose of this study was to explore the effect of omega-3 polyunsaturated fatty acids (n-3 PUFAs) supplementation on serum lipid profile and blood pressure in patients with metabolic syndrome. We searched PubMed, Web of Science, Embase, and the ...