Could fish oil lower risk of type 2 diabetes mellitus?

Tuesday June 10, 2014 (foodconsumer.org) -- A new study this year in Diabetes Care suggests that eating oily fish or taking omega-3 fatty acid supplements can reduce the risk of type 2 diabetes mellitus in adult men.

Fish consumption and omega-3 polyunsaturated fatty acids have been associated with reduced risk of type 2 diabetes mellitus, but not all studies are consistent.  The current study sought to find more evidence to either prove or disprove the association between fish consumption and risk of type2 diabetes mellitus.

The study shows that men in the highest quartile of serum eicosapentaenoic acid + docosapentaenoic acid + docosahexaenoic acid were 33% less likely to develop type 2 diabetes mellitus than those in the lowest quartile.

For the study, researchers investigated "the associations between serum omega-3 PUFAs eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), α-linolenic acid (ALA), hair mercury, and risk of incident type 2 diabetes in middle-aged and older Finnish men."

Participated in the study were 2212 men from 2,212 men from the prospective, population-based Kuopio Ischemic Heart Disease Risk Factor cohort. Participants aged 42 to 60 were free of type 2 diabetes mellitus at baseline between 1984 and 1989.

During the average 19.3-year follow-up, a total of 422 men developed type 2 diabetes mellitus. Men in the highest serum EPA + DPA + DHA quartile were 33% reduced risk for type 2 diabetes after adjustment for confounders.

However, serum or dietary ALA, dietary intake of fish or EPA + DHA, or hair mercury were not associated with risk of type 2 diabetes mellitus.

The study concluded "Serum long-chain omega-3 PUFA concentration, an objective biomarker for fish intake, was associated with long-term lower risk of type 2 diabetes."

This is merely an observational study which does not prove that eating fish reduces the risk of type 2 diabetes mellitus.  Chances are good that those who eat fish more often may follow a healthier diet, which may explain why these people are a lower risk for type 2 diabetes mellitus.

Many dietary factors can increase risk of type 2 diabetes mellitus.  For instance, high intake of trans fat and saturated fat can increase the risk.  And also added sugar can also increase the risk.  (David Liu, PHD)

Reference

Jyrki K. Virtanen, Jaakko Mursu, Sari Voutilainen, Matti Uusitupa and Tomi-Pekka Tuomainen, Serum Omega-3 Polyunsaturated Fatty Acids and Risk of Incident Type 2 Diabetes in Men: The Kuopio Ischemic Heart Disease Risk Factor Study, Diabetes Care, 2014