Milk-alternative drinks do not replace the iodine in cows' milk

Consumers of milk-alternative drinks may be at of risk iodine deficiency, according to the findings of a new study in the British Journal of Nutrition.

In the first study of its kind in the United Kingdom, researchers from the University of Surrey examined the iodine content of 47 milk-alternative drinks (including soya, almond, coconut, oat, rice, hazelnut and hemp, but excluding those marketed specifically at infants and children) and compared it with that of cows' milk.

Researchers discovered that the majority of milk-alternative drinks did not have adequate levels of iodine, with concentration levels found to be around 2% of that found in cows' milk. Cows' milk and dairy products are the main source of iodine in the diet however findings from the study show that most milk-alternative drinks are not an adequate substitute. 

Iodine is required to make thyroid hormones, and is particularly important during pregnancy as it is essential for normal foetal brain development. Previous research in this area by the University of Surrey has shown that low iodine status in pregnant mothers is linked to lower IQ and reading scores in their children (up to 9 years of age).

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. 

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.. If considering taking an iodine supplement, you should avoid kelp which can provide excessive amounts of iodine.