Supplementation with a blend of krill and salmon oil is associated with increased metabolic risk in overweight men. Issue 1 (27th May 2015)

• Record Type: Journal Article
• Authors: Albert, Benjamin B; Derraik, José GB; Brennan, Christine M; Biggs, Janene B; Garg, Manohar L; Cameron-Smith, David; Hofman, Paul L; Cutfield, Wayne S
• Is Part Of: American journal of clinical nutrition. Volume 102:Issue 1(2015)
• Page Start: 49
• Page End: 57
• Publication Date: 2015-05-27
• Subjects: cholesterol -- omega-3 -- insulin sensitivity -- lipids -- males -- n−3 PUFA -- nutraceutical; Diet therapy -- Periodicals; Nutrition -- Periodicals; Dietetics -- Periodicals; 613.205
• DOI: 10.3945/ajcn.114.103028
• Languages: English
• ISSNs: 0002-9165

Abstract

ABSTRACT: Background: Krill is an increasingly popular source of marine n−3 (ω-3) PUFA that is seen as a premium product. However, to our knowledge, the effect of krill-oil supplementation on insulin sensitivity in humans has not been reported. Objective: We assessed whether supplementation with a blend of krill and salmon (KS) oil [which is rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] affects insulin sensitivity in overweight men. Design: The design was a randomized, double-blind, controlled crossover trial. A total of 47 men with a mean ± SD age of 46.5 ± 5.1 y, who were overweight [body mass index (in kg/m 2 ) from 25 to 30] but otherwise healthy, received 5 1-g capsules of KS oil or a control (canola oil) for 8 wk and crossed over to another treatment after an 8-wk washout period. The primary outcome was insulin sensitivity assessed by using the Matsuda method from an oral-glucose-tolerance test. Secondary outcomes included lipid profiles, inflammatory markers, 24-h ambulatory blood pressure, and carotid artery intimamedia thickness. Results: Unexpectedly, insulin sensitivity (per the Matsuda index) was 14% lower with the KS oil than with the control oil ( P = 0.049). A mediation analysis showed that, after controlling for the likely positive effects of blood EPA and DHA (i.e., the omega-3 index), the reduction in insulin sensitivity after KS-oil supplementation was more marked [27% lower than with the control oil ( P = 0.009)]. Conclusions: Supplementation with a blend of KS oil is associated with decreased insulin sensitivity. Thus, krill-oil supplementation in overweight adults could exacerbate risk of diabetes and cardiovascular disease. This trial was prospectively registered at the Australian New Zealand Clinical Trials Registry as ACTRN12611000602921.