Effects of feeding regular eggs, n-3 fatty acid enriched eggs, and walnuts, on blood lipids, membrane incorporation of fatty acids, and serum lutein, in free-living lacto-ovo vegetarians.

摘要

Americans do not receive enough n-3 fatty acids (F.A.) in their diets. Walnuts are good source of alpha-linolenic acid (ALA), while n-3 F.A. enriched eggs provide a dietary source of DHA. Whether ALA and DHA have equivalent effects modifying cardiovascular risk factors is not known. This study compared the changes in blood and erythrocyte membrane lipids in twenty free-living lacto-ovo vegetarians following the consumption of regular eggs (6/wk), n-3 F.A. enriched eggs (6/wk), or walnuts (6 oz/wk) in a triple crossover design.; Results indicate significant differences between treatments for serum triacylglycerols (TAGs), total cholesterol (TC), apo B, apo B: apo A ratio, TC: HDL ratio, and membrane differences for linolenic acid (LA), ALA, DHA, MUFA, and the ALA: LA ratio. Paired comparisons showed the walnut treatment had significantly lower values of serum TAGS, TC, apo B, apo B: apo A ratio, and TC: HDL ratio than the regular egg treatment. Walnuts significantly increased erythrocyte membrane ALA and LA compared to the egg treatments, and n-3 F.A. enriched eggs increased membrane DHA compared to the walnut treatment. The regular egg treatment increased serum TC, HDL, LDL, apo A, apo B, and the apo B: apo A ratio from baseline. The walnut treatment decreased the TC: HDL ratio, and the n-3 F.A. enriched egg treatment did not significantly change any of the blood lipid values from baseline.; We conclude walnuts and n-3 F.A. enriched eggs provide essential n-3 F.A. and may maintain optimum blood lipid parameters in healthy populations.; Lutein is a phytochemical found in egg yolk, dark green leafy and Brassica vegetables. Lutein may protect against some cancers, atherosclerosis and CVD, reduce ultraviolet radiation-induced inflammation, and is an antioxidant that quenches and scavenges photo-induced reactive oxygen species.; We tested the effects of feeding n-3 F.A. enriched eggs from flaxseed-fed chickens and regular eggs on blood serum lutein levels. The results indicate serum lutein was increased by 16.3% on the n-3 F.A. enriched egg treatment (p 0.016) and by 19.1% on the regular egg treatment (p 0.017). We conclude that both types of eggs increase serum lutein levels in healthy lacto-ovo vegetarians.