Milk-alternative drinks could cause iodine deficiency

Milk-alternative drinks such as soya, almond, coconut, oat, rice, hazelnut and hemp could put consumers at risk of iodine deficiency. A study published in the British Journal of Nutrition compared the iodine content of 47 milk-alternative drinks with cows’ milk.

Dairy products are the main source of iodine in the UK diet, but with the popularity of milk alternatives increasing due to dietary requirements and perceived health benefits, many consumers are not receiving sufficient iodine levels. The study, conducted by the University of Surrey in the UK, found that milk-alternative drinks had concentration levels of around 2% of that found in cows’ milk.

“Many people are unaware of the need for this vital dietary mineral and it is important that people who consume milk-alternative drinks realise that they will not be replacing the iodine from cows’ milk, which is the main UK source of iodine,” said Margaret Rayman, Professor of Nutritional Medicine at the University of Surrey.

This suggests that most milk-alternative drinks are not an adequate substitute for the dairy product, and this could be having important health effects. Iodine is required to make thyroid hormones, which is particularly important for brain development during pregnancy, and it has been linked to lower IQ.

“A glass of a milk-alternative drink would only provide around 2 mcg of iodine, which is a very small proportion of the adult recommended iodine intake of 150 mcg/day. In pregnancy, that recommendation goes up to 200 mcg/day,” Rayman explained.

The failure to list iodine on the nutrition information labels on milk containers in the UK means there is little knowledge about the importance of iodine intake and its sources. Iodine intake can be increased by consuming more cows’ milk, white fish and eggs, or for those who are allergic to dairy or are vegetarian, iodine supplements may also help prevent deficiencies.

Dr Sarah Bath, Lecturer in Public Health Nutrition at the University of Surrey and registered dietitian, said: “Worryingly, most milk-alternative drinks are not fortified with iodine and their iodine content is very low. If avoiding milk and dairy products, consumers need to ensure that they have iodine from other dietary sources, where possible. More information on good iodine sources such as white fish can be found in the British Dietetic Association Iodine Food Fact Sheet. If considering taking an iodine supplement, they should avoid kelp, which can provide excessive amounts of iodine.”