Study: replacing dairy with unfortified plant-based products could lower UK iodine intake

Mixed · 2A study in The Lancet Planetary Health found that switching from dairy products to plant-based alternatives could lead to deficiencies in iodine, calcium, riboflavin and vitamin B12, especially among young people and women, if the substitutes are not fortified. 1 2 Mixed · 2The researchers, from the University of Surrey and Queen's University Belfast, examined the UK market and found that 61% of the plant-based products had added calcium and 46% added vitamin B12, but only 19% were fortified with riboflavin and 12% with iodine. 1 2 Mixed · 2The Guardian reports the products analysed as 146 non-dairy milks, 76 yoghurts and 67 cheeses; the Daily Mail gives 164 milks, with the same figures for yoghurts and cheeses. 1 2

Mixed · 2Iodine was the greatest concern. According to the modelling, replacing a fifth to a third of dairy intake with plant-based alternatives would raise the prevalence of inadequate iodine intake from 54% to 65% among adolescent girls and from 32% to 42% among women aged 19 to 49. 1 2 Mixed · 2Replacing all dairy with non-dairy alternatives would push inadequate iodine intake to 80% of teenage girls and 72% of teenage boys. The Guardian adds that swapping a third of dairy led to a 9% to 21% fall in iodine intake. 1 2 Right · 1The Daily Mail also reports calcium effects: around a third of teenage boys already fail to get enough calcium, rising to almost half after the swap, and 70% of teenage girls would fall short if all dairy were replaced. 2

Mixed · 2Dairy is a major iodine source in the UK: according to the Guardian, children get about half and adults about a third of their iodine from dairy, and there is no formal requirement to fortify vegan alternatives. Dr Sarah Bath of the University of Surrey said the UK is particularly vulnerable because it has no iodine fortification policy such as universal salt iodisation. 1 2 Mixed · 2The study found that requiring fortification of all non-dairy alternatives with iodine would prevent average declines, and that adding iodised salt to bread would help reduce the share of teenage girls with inadequate intake. Co-author Dr Katie Nicol said government policy is needed to make fortification happen. 1 2 Mixed · 2Some manufacturers already fortify. Danone's UK head of nutrition and science communications, Niamh Brannelly, said its core Alpro range is fortified with calcium, iodine and vitamins B2 and B12, and Oatly's Caroline Orfila Jenkins said all its unflavoured, non-organic oat drinks are fortified with nutrients including iodine. The Daily Mail also names M&S's Plant Kitchen range, and notes that organic alternatives cannot legally be fortified. 1 2

Mixed · 2Experts not involved in the study gave measured responses. Dietitian Nichola Ludlam-Raine of the British Dietetic Association said it raised a population-level concern but did not mean everyone who switched would become deficient, and advised choosing iodine-fortified drinks and avoiding reliance on seaweed or kelp supplements. Professor Keith Frayn of the University of Oxford said the paper presented credible alternatives that largely but not completely alleviate the deficiencies. 1 2 Mixed · 2The Daily Mail goes further on health effects, saying iodine deficiency could cause weight gain, memory problems and chronic fatigue, and that mild deficiency in pregnancy can impair children's cognition; the Guardian describes iodine's role in thyroid hormones, metabolism and brain development without listing symptoms. 2 1