Uauy Ricardo, Dangour Alan D
Nutrition and Public Health Intervention Research Unit, London School of Hygiene & Tropical Medicine, United Kingdom.
Nutr Rev. 2006 May;64(5 Pt 2):S24-33; discussion S72-91. doi: 10.1301/nr.2006.may.s24-s33.
The essential fatty acids (EFAs), particularly the n-3 long-chain polyunsaturated fatty acids (LCPs), are important for brain development during both the fetal and postnatal period. They are also increasingly seen to be of value in limiting the cognitive decline during aging. EFA deficiency was first shown over 75 years ago, but the more subtle effects of the n-3 fatty acids in terms of skin changes, a poor response to linoleic acid supplementation, abnormal visual function, and peripheral neuropathy were only discovered later. Both n-3 and n-6 LCPs play important roles in neuronal growth, development of synaptic processing of neural cell interaction, and expression of genes regulating cell differentiation and growth. The fetus and placenta are dependent on maternal EFA supply for their growth and development, with docosahexaenomic acid (DHA)-supplemented infants showing significantly greater mental and psychomotor development scores (breast-fed children do even better). Dietary DHA is needed for the optimum functional maturation of the retina and visual cortex, with visual acuity and mental development seemingly improved by extra DHA. Aging is also associated with decreased brain levels of DHA: fish consumption is associated with decreased risk of dementia and Alzheimer's disease, and the reported daily use of fish-oil supplements has been linked to improved cognitive function scores, but confirmation of these effects is needed.
必需脂肪酸（EFAs），尤其是n-3长链多不饱和脂肪酸（LCPs），在胎儿期和出生后对大脑发育都很重要。人们也越来越多地认识到它们在限制衰老过程中的认知能力下降方面具有价值。75多年前首次发现必需脂肪酸缺乏，但n-3脂肪酸在皮肤变化、对亚油酸补充剂反应不佳、视觉功能异常和周围神经病变等方面的更细微影响后来才被发现。n-3和n-6 LCPs在神经元生长、神经细胞相互作用的突触加工发育以及调节细胞分化和生长的基因表达中都发挥着重要作用。胎儿和胎盘的生长发育依赖于母体必需脂肪酸的供应，补充二十二碳六烯酸（DHA）的婴儿在智力和心理运动发育方面的得分显著更高（母乳喂养的儿童表现更好）。视网膜和视觉皮层的最佳功能成熟需要膳食DHA，额外的DHA似乎能提高视力和智力发育。衰老还与大脑中DHA水平降低有关：食用鱼类与降低患痴呆症和阿尔茨海默病的风险有关，报告的每日服用鱼油补充剂与改善认知功能得分有关，但这些效果仍需证实。
