Lipid-modifying effects of krill oil vs fish oil: a network meta-analysis

Abstract

Krill oil is a good source of n-3 phospholipids and has greater bioavailability than fish oil, which contains n-3 triglycerides. However, it is unclear whether krill oil affects circulating lipid concentrations more beneficially than fish oil. A network meta-analysis was conducted to compare the lipid-modifying effects of krill oil and fish oil. PubMed and Embase databases were searched. A total of 64 randomized controlled trials that determined the lipid-modifying effects of krill oil or fish oil were selected. The MetaXL program was used for meta-analysis. A subgroup analysis and a network meta-regression were conducted to investigate the dose-response effect of the n-3 fatty acid content of fish oil and krill oil. Krill oil was associated with significantly lower triglyceride levels than control supplements (weighted mean difference [WMD] -23.26 [95%CI, -38.84 to -7.69]). However, the net differences in triglycerides (WMD -4.07 [95%CI, -15.22 to 7.08]), low-density lipoprotein cholesterol (WMD 3.01 [95%CI, -5.49 to 11.51]), high-density lipoprotein cholesterol (WMD 1.37 [95%CI, -3.73 to 6.48]), and total cholesterol (WMD 1.69 [95%CI, -6.62 to 10.01]) were not significantly different between the krill oil and fish oil groups. One gram of n-3 fatty acids contained in fish oil and krill oil lowered median triglycerides by 8.971 mg/dL (95% credible interval [CrI], 2.27 to 14.04) and 9.838 mg/dL (95%CrI, 0.72 to 19.40), respectively. The lipid-modifying effects of krill oil and fish oil do not differ. The reduction in triglycerides depends on the dose of n-3 fatty acids consumed.