A new study published in Diabetes Care has linked consumption of fish-derived omega-three polyunsaturated fatty acids (PUFAs) with decreased risk for type 2 diabetes.
The study was done in Finland and found that men with the highest blood levels of PUFAs had over one third lower risk for developing type 2 diabetes than men who had the lowest levels of PUFAs.
Fish-derived PUFAs have been lauded for improving symptoms in a variety of disorders linked to inflammation, such as rheumatoid arthritis, inflammatory bowel disease, and Alzheimer’s disease. Though the jury is still out, inflammation is also thought by some researchers to be at the root of type 2 diabetes. Controversy exists, though, about the interplay between the benefits of PUFAs and mercury, a common contaminant of fish.
The researchers looked at 2,212 Finnish men aged 42-60 who were recruited into the Kuopio Ischemic Heart Risk Factor Study between the years 1984-1989. Food questionnaires were used to investigate four dietary omega-3 PUFAs: eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), and α-linolenic acid (ALA). The researchers also looked at hair mercury as a proxy for accumulation of mercury in the body. Risk of type 2 diabetes was analyzed using questionnaires, oral glucose tolerance tests, and hospital records.
The men were followed for roughly 19 years, during which time 422 men developed type 2 diabetes. Men with the highest levels of PUFAs had 33% lower risk for type 2 diabetes, compared to men with the lowest levels of PUFAs. The researchers failed to find a statistically significant association between dietary PUFAs and levels of mercury in the hair, which may indicate that high levels of fish consumption are not necessarily associated with an accumulation of higher levels of mercury in the body, at least in this study.
The major caveat concerning this study is generalizability. Results from the Finnish population may not generalize to larger, more diverse populations, like those in the United States.
Nevetheless, the results add to evidence about the benefits of fish-derived PUFAs. The Mediterranean Diet recommends at least two fish meals per week, preferably with fatty fish like tuna, salmon, herring, anchovy, sardines, mackerel, and sword fish. It’s fun to learn about all the different kinds of fish, and invent creative ways of preparing them!
Citation: Jyrki K. Virtanen, Jaakko Mursu, Sari Voutilainen, Matti Uusitupa, Tomi-Pekka Tuomainen. Serum Omega-3 Polyunsaturated Fatty Acids and Risk of Incident Type 2 Diabetes in Men: The Kuopio Ischaemic Heart Disease Risk Factor Study. Diabetes Care 2014;37(1):189-96.
Grilled, Marinated Swordfish: http://commons.wikimedia.org/wiki/File%3AMarinated_grill_swordfish.jpeg
By Kevin Saff at en.wikipedia [Public domain], from Wikimedia Commons
By Alpha (originally posted to Flickr as Tuna Salad) [CC-BY-SA-2.0 (http://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons
Grilled Salmon with Turmeric and Dill:http://commons.wikimedia.org/wiki/File%3AB%C3%BAn_C%C3%A1_H%C3%A0_N%E1%BB%99i.jpg
By Ron Diggity (originally posted to Flickr as Bún Cá Hà Nội) [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons