n-3 fatty acids do not decrease plasma endothelin levels in healthy individuals

The effect of three different doses of n-3 polyunsaturated fatty acids (PUFA) on endothelin-1 (ET-1) was studied. Study 1 included 40 healthy volunteers randomized to a single supplement of 20 g of n-3 or n-6 PUFA. Plasma ET-1 was measured 14 h after ingestion, and no changes in plasma ET-1 after intake of n-3 PUFA were observed, compared to baseline values. In study 2, 32 subjects had 0.65 g of n-3 PUFA or a fat mixture per day for 12 weeks. No changes in plasma ET-1 were found after the oil supplements. Finally, 22 persons had 4 g of n-3 PUFA for 6 weeks. A significant increase in plasma ET-1 was seen in this group after the supplement. Thus, n-3 PUFAs do not lower plasma levels of ET-1, the most potent vasoconstrictor known.