Do n-3 fatty acids improve glucose tolerance and lipemia in diabetics?

A protective effect of habitual fish consumption on the development of impaired glucose tolerance and diabetes is once again suggested in a recent trial. In nondiabetic individuals with essential hypertension, a group known to be insulin resistant, fish oil was not associated with a negative impact on glycemic control, insulin secretion or peripheral insulin sensitivity, even in a subgroup who had impaired glucose tolerance. Furthermore, more recent, long term, placebo-controlled trials in type II patients have failed to demonstrate a significant impact of fish oil supplementation on glycemic control. Additional information is available regarding qualitative changes in VLDL- and LDL-lipoproteins in type II diabetes patients in response to dietary fish oil supplementation. The impact of fish oil on LDL oxidation is the focus of two recent trials. Vitamin E supplementation may mitigate much of the enhanced oxidation of LDL that is potentially seen with dietary fish oil supplementation.