Supplementation with a blend of krill and salmon oil is associated with increased metabolic risk in overweight men.

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.

• Authors: Benjamin B Albert, José G B Derraik, Christine M Brennan, Janene B Biggs, Manohar L Garg, David Cameron-Smith, Paul L Hofman, Wayne S Cutfield
• Journal: The American journal of clinical nutrition (Am J Clin Nutr) Vol. 102 Issue 1 Pg. 49-57 (Jul 2015) ISSN: 1938-3207 [Electronic] United States
• PMID: 26016867 (Publication Type: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
• Copyright: © 2015 American Society for Nutrition.

Chemical References

• Fatty Acids, Monounsaturated
• Fish Oils
• Rapeseed Oil
• Docosahexaenoic Acids
• salmon oil
• Eicosapentaenoic Acid

Topics

• Adult
• Animals
• Blood Pressure Monitoring, Ambulatory
• Body Mass Index
• Cardiovascular Diseases (blood, epidemiology)
• Cross-Over Studies
• Diabetes Mellitus (epidemiology)
• Dietary Supplements
• Docosahexaenoic Acids (administration & dosage, blood)
• Double-Blind Method
• Eicosapentaenoic Acid (administration & dosage, blood)
• Euphausiacea
• Fatty Acids, Monounsaturated (administration & dosage)
• Fish Oils (administration & dosage, adverse effects)
• Glucose Tolerance Test
• Humans
• Insulin Resistance
• Male
• Middle Aged
• Motor Activity
• New Zealand
• Overweight (physiopathology)
• Rapeseed Oil
• Risk Factors
• Salmon
• Treatment Outcome