ResearchReviewn-3 long-chain polyunsaturated fatty acids in type 2 diabetes: A review
Section snippets
Epidemiologic studies
More than 30 years ago disease patterns among the Greenland Inuit, Alaskan natives, and other Arctic and subarctic natives showed far lower incidence of type 2 diabetes than in Danes, US residents, or others (26, 27, 28, 29). Type 2 diabetes was less prevalent among Japanese islanders compared to their mainland counterparts (30). Lower prevalence of type 2 diabetes was attributed mainly to diets rich in n-3 LC-PUFAs. During the past 15 years, the incidence of type 2 diabetes has increased
Glucose control
In a review, Nettleton (44) noted that several clinical studies in the 1980s and early 1990s reported adverse effects on blood glucose control and insulin activity in subjects with type 2 diabetes who consumed large amounts of fish oil (45, 46). It is now believed that these deleterious effects were largely attributable to the high doses used, like 10 g fish oil per day or more. Recent studies using low doses of n-3 LC-PUFAs, ranging from 1 to 2 g/day, have reported no deterioration in glucose
Implications
Promising results from studies of patients with insulin resistance and type 2 diabetes indicate that consumption of n-3 LC-PUFAs improves lipid profiles, may retard disease progression, modestly reduces blood pressure, and may deter the onset of more serious cardiovascular complications, including mortality. However, proof that n-3 LC-PUFAs can prevent subjects with insulin resistance or impaired glucose tolerance from developing type 2 diabetes remains to be established. Effects of n-3
J. A. Nettleton is principal, ScienceVoice Consulting, Denver, CO.
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J. A. Nettleton is principal, ScienceVoice Consulting, Denver, CO.
R. Katz is president, Omega-3 Research Institute, Inc, Bethesda, MD.