[The effect of dietary supplementation with long-chain polyunsaturated fatty acids of the n-3 and n-6 series and with vitamin E on the plasma fatty acid profile].

Dietary supplement with long-chain polyunsaturated fatty acids from the series n-3 and n-5 appears to be advisable in the nutritional repletion of a variety of conditions. It must be associated with the addition of a sufficient amount of an anti-oxidant to prevent the oxidative degradation of such fatty acids. The purpose of this study was to appraise the effect of the dietary addition of long-chain polyunsaturated fatty acids from the series n-3 and n-5 and of Vitamin E on the fatty acid profile of the plasma, and its lipidic fractions. Five groups of weaning rats were fed for a month as follows: Group A, a semipurified diet with 10% of fat [18:1(n-9) 40%; 18:2(n-6) 12%; 18:3(n-3) 1.2%]; Groups B and C, a semipurified diet with 7% of fat A and 3% of a marine oil concentrate; Groups D and E, a semipurified diet with 7% of fat A, 1.5% of a marine oil concentrate and 1.5% of a phospholipid concentrate of animal origin. Groups B and D were supplemented with 0.5 g of Vitamin E per kilogram of fat. The results obtained suggest that dietary supplement is necessary with long-chain polyunsaturated fatty acids from both the n-3 and n-5 series in order to maintain plasmatic levels of 20:4(n-6) and of 22:6(n-3) in the face of the tissular inability to produce them from their dietary precursors [18:2(n-6) and 18:3)], along with Vitamin E to prevent the oxidative malnutrition of these fatty acids.