Metabolic Effects of Omega‐3 Fatty Acids in Type 2 (Non‐Insulin‐Dependent) Diabetic Patients

Abstract

The metabolic effects of a 3-week dietary supplement of a fish oil concentrate was examined in mildly obese, normotriglyceridemic men with non-insulin-dependent diabetes mellitus (NIDDM) treated with hypoglycemic agents (n = 20). Patients were randomized into two groups, receiving 15 ml per day of fish oil (Martens Oil, Norway) containing 3.1 g of omega-3 fatty acids (FA) (n = 10) or placebo (n = 10). Whereas fish oil led to the expected increase in the ratio of omega-3 to omega-6 FA in serum phospholipids, reflecting the increase in omega-3 FA intake, it did not alter fasting or mixed meal stimulated blood glucose, plasma insulin, and C-peptide concentrations. No changes in insulin action were noted, estimated by the metabolic clearance rates of glucose at plasma insulin levels of approximately 100 microU/ml and 1,400 microU/ml during a hyperinsulinemic, isoglycemic clamp; no changes were seen in insulin binding to erythrocytes. We conclude that during short-term administration, no adverse effects of low dose fish oil on glucose homeostasis were found in mildly obese NIDDM patients treated with oral hypoglycemic agents.

Meta-analysis of the effects of n-3 polyunsaturated fatty acids on lipoproteins and other emerging lipid cardiovascular risk markers in patients with type 2 diabetes

“…Data from six additional trials could not be pooled. Five of these reported no significant change in TC [23,29,45,52,53]; one trial reported an increase [24].…”

“…The trials included in the pooled analyses were small, with a median of 23 patients. Seventeen of the published papers were duplicate publications of six trials [22, 27, 33, 34, 36-38, 40, 42-46, 48, 51, 54, 55]; multiple papers for each trial are indicated by the following grouping of references: [22,38], [27,34,36,37], [40,54,55], [42,48,51], [43,46], [44,45]. There was sufficient information on only 12 of the 98 outcomes to allow data to be pooled, the results of which are shown in Fig.…”

“…1, while Table 2 lists all the outcomes measured by the respective trials identified in the search. Trials included both men and women, except for one trial including only men [45]. Two trials excluded premenopausal women [51,54].…”

“…Data from six additional trials could not be pooled. Three of these reported an increase in LDL-cholesterol [23,25,53] and three reported no change [24,45,52] (Table 2).…”

A cross-sectional study of dietary habits and urinary glucose excretion — a predictor of non-insulin-dependent diabetes mellitus

“…At least one previous follow-up study has suggested that ®sh consumption reduce the risk for NIDDM in both men and women (Feskens et al, 1991). The effect might be ascribed to the fact that n ± 3 polyunsaturated fatty acids from ®sh oils improve insulin sensitivity (Yam et al, 1996), although recent studies of n ± 3 supplementation in NIDDM patients show no bene®cial effects on glucose tolerance or insulin resistance (Fasching et al, 1991;Pelikanova et al, 1993), and the lack of an association for men makes the observation more questionable.…”