Omega-3 fatty acid supply from milk associates with lower type 2 diabetes in men and coronary heart disease in women

Background. Omega-3 fatty acids may prevent type 2 diabetes and coronary heart disease (CHD). We investigated these fatty acids in Nordic cow's milk and whether their supply from milk associates with type 2 diabetes prevalence and CHD mortality in the Nordic countries. Methods. Samples (N = 84) of consumers' milk were collected in five Nordic countries four times during 1 year. Fatty acids were analyzed using gas chromatography. Fatty acids supply from milk fat was calculated using national food balance sheets. Results. The omega-3 fatty acids content was higher and omega-6 fatty acid content was lower in Icelandic milk when compared with milk from other Nordic countries. Type 2 diabetes prevalence in men correlated inversely with the supply of omega-3 fatty acids and eicosapentaenic acid, but positively with omega-6/omega-3 ratio in milk. CHD mortality in women correlated inversely with the supply of eicosapentaenic acid but positively with the omega-6/omega-3 ratio. Conclusions. Milk fatty acids content can depend upon the origin of the milk. The higher supply of omega-3 fatty acids from milk might explain the lower type 2 diabetes prevalence and CHD mortality in Iceland compared to the other Nordic countries.