Krill oil supplementation supports lipid metabolism, meta-analysis shows
Highlights
- Meta-analysis of 7 randomized, controlled trials involving over 660 participants
- Krill oil supplementation helps maintain blood lipids and lipoproteins in the normal range
- Most effective dosages are at least 2 g/day for at least 12 weeks
Summary
This meta-analysis was performed to determine the overall efficacy of krill oil on plasma lipids.
Inclusion criteria included only randomized, controlled trials that investigated krill oil effects on at least one main blood lipid parameter (e.g., total, LDL, or HDL cholesterol or triglycerides), included net change data from baseline to follow up, and administered krill oil for at least 2 weeks.
A total of 7 trials (14 treatment arms) were included in the final meta-analysis with 427 participants allocated to a krill oil supplementation group and 235 to a control group. The studies were published between 2004 and 2015 and conducted in Canada, Norway, and the United States. All studies used 500-mg capsules or softgels of krill oil, and the dosages ranged from 500 mg/day to 4 g/day. Duration of supplementation with krill oil ranged between 4 weeks and 3 months.
Overall, results indicate krill oil supplementation has a significant effect on improving blood lipids and lipoproteins. Weighted mean differences (WMD), 95% confidence intervals (CI) and levels of significance (P) of parameters analyzed include:
- Total Cholesterol: WMD: -7.5 mg/dL (95% CI: -17.94 to 2.9) (P=.159) (not significant)
- LDL Cholesterol: WMD: -15.52 mg/dL (95% CI: -28.43 to -2.61) (P<.02)
- HDL Cholesterol: WMD: 6.65 mg/dL (95% CI: 2.30 to 10.99) (P=.003)
- Triglycerides: WMD: -14.03 mg/dL (95% CI: -21.38 to -6.67) (P<.001)
Subgroup analyses based on dosage indicate significant changes in HDL cholesterol only remained for dosages of 2 g/day or more, while significance remained for all dosages of triglycerides.
Subgroup analyses based on treatment duration reveal the reduction in total cholesterol reached significance with longer treatments (P<.03). Separately, significance for changes in LDL cholesterol and triglycerides remained only for trials lasting at least 12 weeks. For HDL cholesterol, both shorter and longer trials had a significant effect.
These findings indicate krill oil supplementation may offer value as an add-on therapy for treatment of patients with dyslipidemia, especially in dosages of at least 2 g/day for at least 12 weeks.
