Innis Sheila M
Child and Family Research Institute and Department of Paediatrics, University of British Columbia, Vancouver, British Columbia, Canada.
J Pediatr Gastroenterol Nutr. 2009 Mar;48 Suppl 1:S16-24. doi: 10.1097/MPG.0b013e31819773cf.
The omega (omega)-3 fatty acids are essential nutrients, explained by the absence of a Delta-15 desaturase in mammalian cells. The omega-3 fatty acids are found in the diet as alpha-linolenic acid (18:3omega-3) and eicosapentaenoic acid (20:5omega-3), as well as docosahexaenoic acid (DHA), with different functions of each of the omega-3 fatty acids in different cells. One essential role of the omega-3 fatty acids is fulfilled by the 22 carbon DHA (22:6omega-3). Depletion of DHA from brain and retina interferes with normal neurogenesis and neurological function, and visual signaling pathways. Observation and intervention studies with pregnant and lactating women, and with infants fed some formulas show that dietary DHA is associated with higher scores on tests of visual and neural development in infants and children. The estimated average requirement and variability in requirement among individuals both of which are needed to set dietary recommended intakes (DRIs) for the different omega-3 fatty acids are unknown. However, because omega-3 fatty acids are essential, adequate intakes to minimize risk of poor neural development and function can be justified, but dose-response data to provide a safe upper limit with different omega-6 fatty acid intakes are needed. Dietary recommendations do affect the food supply and supplements and are used in labeling, all impacting population health. When scientific information is incomplete, consideration must be given to the implications of recommendations that focus on individual nutrients, rather than dietary patterns such as breast-feeding and consuming fish that promote health and minimize disease risk.
ω-3脂肪酸是必需营养素，这是由于哺乳动物细胞中缺乏Δ-15去饱和酶所致。ω-3脂肪酸在饮食中以α-亚麻酸（18:3ω-3）、二十碳五烯酸（20:5ω-3）以及二十二碳六烯酸（DHA）的形式存在，每种ω-3脂肪酸在不同细胞中具有不同功能。二十二碳的DHA（22:6ω-3）发挥着ω-3脂肪酸的一项重要作用。从大脑和视网膜中耗尽DHA会干扰正常的神经发生和神经功能以及视觉信号通路。对孕妇和哺乳期妇女以及食用某些配方奶粉的婴儿进行的观察和干预研究表明，膳食DHA与婴幼儿视觉和神经发育测试中的较高分数相关。设定不同ω-3脂肪酸的膳食推荐摄入量（DRIs）所需的估计平均需求量以及个体之间需求量的变异性均未知。然而，由于ω-3脂肪酸是必需的，为将神经发育不良和功能不佳的风险降至最低而摄入足够量是合理的，但需要剂量反应数据来提供不同ω-6脂肪酸摄入量时的安全上限。膳食建议确实会影响食物供应和补充剂，并用于食品标签，所有这些都会影响人群健康。当科学信息不完整时，必须考虑侧重于个别营养素的建议所带来的影响，而不是像母乳喂养和食用鱼类等促进健康并将疾病风险降至最低的饮食模式。
