Effects of krill oil and lean and fatty fish on cardiovascular risk markers: a randomised controlled trial.

Journal of nutritional science. 2018;7:e3

Plain language summary

Fish consumption and supplementation with omega-3 rich fish oil has been shown to reduce the risk of cardiovascular disease. Krill oil is becoming a popular choice of fish oil for supplementation however few studies have investigated its health benefits. This small (n=36) double blind, randomised controlled trial aimed to assess the different impacts of 8-week consumption of either: krill oil supplements (4g oil daily); 3 fish meals per week (2 oily fish, one lean fish); or placebo of sunflower oil (4g oil daily), on cardiovascular risk markers. The results showed significant positive changes to blood glucose, lipids, phospholipids and cholesterol markers for the krill oil group, compared to the fish group and placebo. Vitamin D levels increased significantly in the fish consumption group compared to krill oil and placebo. Plasma levels of omega-3 fatty acids increased for both the krill oil group and fish consumption group. The authors conclude that krill oil supplementation and fish consumption both have positive health effects in relation to cardiovascular disease and larger studies of longer duration are needed.

Abstract

Fish consumption and supplementation with n-3 fatty acids reduce CVD risk. Krill oil is an alternative source of marine n-3 fatty acids and few studies have investigated its health effects. Thus, we compared krill oil supplementation with the intake of fish with similar amounts of n-3 fatty acids on different cardiovascular risk markers. In an 8-week randomised parallel study, thirty-six healthy subjects aged 18-70 years with fasting serum TAG between 1·3 and 4·0 mmol/l were randomised to receive either fish, krill oil or control oil. In the fish group, subjects consumed lean and fatty fish, according to dietary guidelines. The krill and control group received eight capsules per d containing 4 g oil per d. The weekly intake of marine n-3 fatty acids from fish given in the fish group and from krill oil in the krill group were 4103 and 4654 mg, respectively. Fasting serum TAG did not change between the groups. The level of total lipids (P = 0·007), phospholipids (P = 0·015), cholesterol (P = 0·009), cholesteryl esters (P = 0·022) and non-esterified cholesterol (P = 0·002) in the smallest VLDL subclass increased significantly in response to krill oil supplementation. Blood glucose decreased significantly (P = 0·024) in the krill group and vitamin D increased significantly in the fish group (P = 0·024). Furthermore, plasma levels of marine n-3 fatty acids increased significantly in the fish and krill groups compared with the control (all P ≤ 0·0003). In conclusion, supplementation with krill oil and intake of fish result in health-beneficial effects. Although only krill oil reduced fasting glucose, fish provide health-beneficial nutrients, including vitamin D.

Lifestyle medicine

Patient Centred Factors : Mediators/Omega-3 fatty acids
Environmental Inputs : Diet ; Nutrients
Personal Lifestyle Factors : Nutrition
Functional Laboratory Testing : Blood

Methodological quality

Allocation concealment : Yes
Publication Type : Journal Article

Metadata