Plant-based milk alternatives: can they replace the iodine from UK cow's milk?

Current food systems pose risks to both population and environmental health. Reducing the intake of animal-based foods, such as dairy products, and increasing consumption of plant-based foods align with priorities for addressing climate change and promoting overall health. Plant-based alternatives to cow's milk can be readily substituted for cow's milk without altering meal patterns and food habits, making them a popular choice among those reducing animal-product consumption. However, plant-based milk alternatives do not necessarily provide the same nutrients as cow's milk, particularly essential micronutrients like iodine. While national data indicate that the UK is iodine-replete, certain population subgroups (such as pregnant women, women of reproductive age, and vegans) remain at risk of iodine deficiency. Young women are more likely than other age groups to consume plant-based milk alternatives, heightening public health concerns about iodine insufficiency in this demographic. Current consumers of plant-based milk alternatives in the UK have lower iodine intake and status compared to consumers of cow's milk. Population-level effects of replacing milk with plant-based alternatives vary and depend on factors such as the role of plant-based milk alternatives in the diet (i.e. in addition to, or as a replacement for milk), the presence of other iodine sources in the diet, the consumer's life stage, and whether the alternatives are fortified with iodine. This review examines the literature on plant-based milk alternatives and iodine intake, focusing on implications of this dietary shift and strategies to improve iodine intake in those opting for plant-based milk alternatives in the UK population.