Fish Oil Lowers Triglycerides With Little or No Glycemic Effect in Type 2 Diabetics
WESTPORT, CT (Reuters Health) Oct 2 - The results of a meta-analysis of 18 trials conducted over a 10-year period show that fish oil supplementation for patients with type 2 diabetes lowers triglycerides but has no statistically significant effect on glycemic control.
"This study disproves the long-held belief that fish oil supplementation adversely affects glycemic control in patients with type 2 diabetes," Dr. Victor M. Montori told Reuters Health.
Dr. Montori, of the Mayo Clinic and Foundation, Rochester, Minnesota, and colleagues collected data on glycemic control and lipid levels in 823 patients with type 2 diabetes who took fish oil supplements in daily dosages ranging from 3 g to 18 g. Most patients, who were followed for a mean of 12 weeks, were men between 55 and 65 years of age who had had type 2 diabetes for between 5 and 10 years.
In the September issue of Diabetes Care , the researchers write that "fish oil supplementation did not result in any statistically or clinically significant increase in fasting glucose or glycosylated hemoglobin."
The main effect of fish oil supplementation was "the reduction of triglycerides by an average of 0.56 mmol/L," Dr. Montori told Reuters Health. Conversely, he reported a "small increase [0.21 mmol/L on average] in low-density lipoprotein cholesterol."
The increases in LDL cholesterol and reductions in triglycerides were "most marked in those trials that recruited hypertriglyceridemic subjects and used higher doses of fish oil," the researchers write. They note that triglycerides levels were reduced up to 4 mmol/L in patients with hypertriglyceridemia.
While the pooled data "was not able to elucidate the ideal dose of fish oil needed to achieve large reductions in triglycerides," Dr. Montori said, it suggests that "fish oil may be safe to add to the armamentarium of triglyceride-lowering medication" for people with diabetes.