SUPPLEMENTATION WITH AN ALGAE SOURCE OF DOCOSAHEXAENOIC ACID INCREASES (N-3) FATTY-ACID STATUS AND ALTERS SELECTED RISK-FACTORS FOR HEART-DISEASE IN VEGETARIAN SUBJECTS

The purpose of this double-blind study was to investigate the influenc e of dietary supplementation with an algae source of docosahexaenoic a cid [DHA; 22:6(n-3)], devoid of any eicosapentaenoic acid [EPA; 20:5(n -3)], on serum/platelet DHA status, the estimated retroconversion of D HA to EPA, and risk factors for heart disease in vegetarian subjects. Healthy vegetarians (12 male, 12 female) consumed nine capsules daily of either DHA (1.62 g/d) or corn oil for 6 wk. Consumption of DHA caps ules increased DHA levels in serum phospholipid by 246% (from 2.4 to 8 .3 g/100 g fatty acids) and in platelet phospholipid by 225% (from 1.2 to 3.9 g/100 g fatty acids). EPA levels increased in serum phospholip id by 117% (from 0.57 to 1.3 g/100 g fatty acids) and in platelet phos pholipid by 176% (0.21 to 0.58 g/100 g fatty acids) via metabolic retr oconversion; the estimated extent of DHA retroconversion to EPA was 11 .3 and 12.0%, based on the serum and platelet analyses, respectively. Arachidonic acid [AA; 20:4(n-6)] levels in serum and platelet phosphol ipids decreased moderately during the trial period (DHA group) as did both docosapentaenoic acids [22:5(n-6) and 22:5(n-3)]. Although no sig nificant changes were found in the total and LDL-cholesterol levels wi th DHA supplementation, the total cholesterol:HDL-cholesterol ratio sh owed a moderate decrease over time as did the LDL-cholesterol: HDL-cho lesterol ratio and serum triglyceride concentrations. DHA supplementat ion did not alter the various thrombogenic factors measured. In conclu sion, DHA supplementation markedly enhanced the DHA status (of serum a nd platelets), provided for the formation of substantial EPA, and lowe red the total and LDL-cholesterol:HDL-cholesterol ratios.