Variation in the iodine content of milk, dairy products, and eggs and the implication for UK iodine intake; studies at the farm, retail, and populatio

缺碘在英国的一些群体中很常见，比如育龄妇女。这是一个公共卫生问题，因为即使是怀孕期间轻度到中度的缺乏症也与儿童智商较低有关。在英国和许多国家，牛奶、乳制品和鸡蛋是碘的主要饮食来源，加起来占英国成年人总碘摄入量的40%以上，在儿童中高达68%(国家饮食和营养调查数据，2021年)。我们知道牛奶中的碘浓度有相当大的差异-例如，碘浓度因季节而异，夏季牛奶中的碘含量较低。牛饲料的成分，例如白三叶草，可能会起到促甲状腺作用，减少碘向牛奶中的转移，尽管缺乏数据来证实这一效果。虽然农业实践与牛奶的碘含量之间存在已知的相互作用，但没有关于其对其他乳制品(如酸奶)或鸡蛋的碘含量的影响的数据。估计牛奶、乳制品和鸡蛋的最佳碘浓度是确保人群足够碘摄入量的关键。这在英国尤其如此，因为与许多其他国家不同，英国没有用碘强化盐的政策，在这些国家，加碘的盐是碘的重要来源。

Iodine deficiency is common in some UK groups, such as in women of childbearing age. This is a public-health concern as even mild-to-moderate deficiency during pregnancy is associated with lower IQ in children. In the UK, and many countries, milk, dairy products, and eggs are the main dietary sources of iodine, together contributing over 40% of total iodine intake in UK adults, and up to 68% in children (National Diet & Nutrition Survey data, 2021).We know that there is considerable variation in the iodine concentration in milk - for example iodine concentration varies by season, with lower iodine in summer milk. Components of cattle feed, for example white clover, may act as goitrogens and reduce the transfer of iodine into milk, although data are lacking to confirm this effect. While there is a known interaction between agricultural practice and the iodine content of milk, there are no data on its effects on the iodine content of other dairy products (e.g. yoghurt) or eggs.Estimating the optimum iodine concentration of milk, dairy products, and eggs is key to ensuring adequate iodine intake in the population. This is especially true in the UK as there is no policy to fortify salt with iodine, unlike in many other countries where iodised salt is an important source of iodine.