Taking a combination of different fatty acids in supplements may improve cholesterol levels in healthy women, and lower their risk of heart attack, report Canadian researchers in the recent issue of the American Journal of Clinical Nutrition.
Eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and the omega-6 fatty acid, gamma-linolenic acid (GLA), all have lipid-modifying and anti-inflammatory properties, noted the authors from the University of Guelph in Canada, but they say the effects of mixtures of these fatty acids on plasma lipids and the fatty acid compositions of serum phospholipids have received little attention.
They set out to determine the effects of different levels of GLA supplementation together with a constant intake of EPA and DHA.
Thirty-one women were assigned to one of four groups: the control group took a 4g EPA/DHA combination alone, while the other three received 4g of EPA/DHA with 1g of GLA (group 1), 2g of GLA (group 2) or 4g of GLA (group 3) daily for one month. Plasma lipids and fatty acids of serum phospholipids were measured at the beginning and end of the period.
Plasma triacylglycerol concentrations were significantly lower at the end of the study in the control and first two groups. LDL cholesterol decreased significantly (by 11.3 per cent) in the second group, which was taking 2g of GLA daily with EPA and DHA. Dihomo-gamma-linolenic acid increased significantly in serum phospholipids only in the second and third groups. The team found also that total omega-3 fatty acids increased in all four groups.
The researchers concluded that a mixture of 4g of EPA and DHA and 2g GLA significantly improved blood lipid and fatty acid profiles in healthy women. They estimated that this combination produced a 43 per cent reduction in the 10-year risk of myocardial infarction (heart attack).