Myers Gary J, Davidson Philip W, Strain J J
Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
J Nutr. 2007 Dec;137(12):2805-8. doi: 10.1093/jn/137.12.2805.
There is controversy about the risks and benefits of consuming fish. Fish consumption provides nutrients, some of which are essential for brain growth and development. All fish, however, contain methyl mercury (MeHg), a known neurotoxicant. The toxic effect of MeHg seems most damaging during brain development, and thus, prenatal exposure is of greatest concern. At present the level of prenatal exposure associated with risk to a child's neurodevelopment is not known. Balancing the rewards and possible risks of fish consumption presents a dilemma to consumers and regulatory authorities. We review the nutrients in fish that are important in brain development and the current evidence of risk from MeHg at exposure levels achieved by consuming fish. We then review the findings from a large prospective cohort study of a population that consumes fish daily, the Seychelles Child Development Study. The MeHg content of the fish consumed in the Seychelles is similar to that of ocean fish available in industrialized countries, so they represent a sentinel population for any risk from fish consumption. In the Seychelles, evaluations of the children through 9 y of age show no consistent pattern of adverse associations with prenatal MeHg exposure. Recent studies in the Seychelles have focused on nutrients in fish that might influence a child's development, including long-chain polyunsaturated fatty acids, iodine, iron, and choline. Preliminary findings from this study suggest that the beneficial influence of nutrients from fish may counter any adverse effects of MeHg on the developing nervous system.
食用鱼类的风险与益处存在争议。食用鱼类能提供营养物质，其中一些对大脑的生长和发育至关重要。然而，所有鱼类都含有甲基汞（MeHg），这是一种已知的神经毒素。MeHg的毒性作用在大脑发育过程中似乎最具破坏性，因此，产前接触甲基汞最为令人担忧。目前，尚不清楚与儿童神经发育风险相关的产前接触水平。权衡食用鱼类的益处和可能存在的风险，给消费者和监管机构带来了两难困境。我们回顾了鱼类中对大脑发育重要的营养物质，以及目前关于食用鱼类所达到的接触水平下甲基汞风险的证据。然后，我们回顾了一项对每日食用鱼类人群进行的大型前瞻性队列研究——塞舌尔儿童发育研究的结果。塞舌尔食用的鱼类中的MeHg含量与工业化国家可获得的海洋鱼类相似，因此它们代表了食用鱼类带来任何风险的哨兵人群。在塞舌尔，对9岁以下儿童的评估显示，产前MeHg接触与不良关联没有一致的模式。塞舌尔最近的研究集中在鱼类中可能影响儿童发育的营养物质上，包括长链多不饱和脂肪酸、碘、铁和胆碱。这项研究的初步结果表明，鱼类营养物质的有益影响可能抵消MeHg对发育中的神经系统的任何不利影响。
