A fresh study featured in The Lancet Planetary Health indicates that replacing dairy products with plant-based options could result in shortages of essential micronutrients, particularly amongst women and young people. Researchers discovered that a partial shift toward vegan substitutes for yoghurt, cheese, and milk might cause reductions in vitamin B12, riboflavin, calcium, and iodine if these alternatives lack fortification.
Iodine Deficiencies Threaten Adolescent Girls and Women
The greatest concerns surround iodine, a trace element used by the thyroid gland to produce hormones that regulate metabolism and support healthy growth and brain development. More than half of UK teenage girls already have inadequate iodine intake, the researchers said.
Replacing a fifth to a third of dairy intake with plant-based alternatives would lead to the prevalence of iodine deficiency rising from 54% to 65% of adolescent girls. For women aged 19 to 49 years old, the deficiency rate would jump from 32% to 42%, based on modelling of typical market levels of fortification.
There are known health effects of iodine deficiency and that’s why we want to raise awareness of this,
said Dr Sarah Bath, an associate professor in public health nutrition at the University of Surrey. The population groups that seem to be at risk and have the lowest intakes were the young women and women of childbearing age, and that’s the key life stage where iodine is particularly important.
Market Analysis Reveals Low Fortification Rates Across Non-Dairy Brands
While plant-based alternatives to milk, cheese, and yoghurt have grown in popularity, there is no formal requirement for vegan alternatives to be fortified with micronutrients. In the UK, children get about half, and adults get about a third, of their total iodine intake from dairy products.
The researchers examined 146 non-dairy milks, 76 yoghurts, and 67 cheeses on the UK market. While 61% of these products had added calcium and 46% had added vitamin B12, only 19% were fortified with riboflavin and 12% with iodine.
Under these conditions, substituting vegan options for one-third of regular dairy consumption resulted in a decline in iodine intake ranging from 9% to 21%. Switching entirely to 100% non-dairy alternatives led inadequate levels of iodine to reach 80% in teenage girls and 72% in teenage boys.
Food Industry Response and Dietitian Recommendations
Danone’s head of nutrition and science communications in the UK, Niamh Brannelly, stated that their primary selection of Alpro goods included added iodine, calcium, and vitamins B2 and B12.
Caroline Orfila Jenkins, a vice-president for science and technology at Oatly, stated that every single one of their unflavoured, non-organic oat drinks came enriched with nutrients such as vitamin D, B12, riboflavin, calcium, and iodine. This research underlines the importance of appropriate fortification as diets become more plant-based,
she said.
Requiring all non-dairy alternatives to be fortified with iodine would prevent average declines, the study found. Adding iodised salt to bread also helped reduce the proportion of teenage girls with inadequate iodine intake in the modelled scenarios.
According to Nichola Ludlam-Raine, who works as a spokesperson for the British Dietetic Association alongside her role as a registered dietitian, the research brings to light a significant issue affecting the broader population. However, she noted it did not mean everyone who switched would become nutrient-deficient because overall diet mattered too.
For anyone choosing plant-based milk, I’d recommend checking the label and choosing one fortified with iodine, such as Alpro,
she said. Organic drinks aren’t fortified with added nutrients, so they’re unlikely to provide iodine. White fish such as cod or haddock, as well as eggs and yoghurt and kefir for those who consume them, can also contribute iodine. I wouldn’t recommend relying on seaweed or kelp supplements as an iodine source, as the iodine content can vary widely and may be excessive.
Frequently Asked Questions About Plant-Based Diets and Iodine
Why are young women most at risk from iodine deficiency?
Young women and women aged 19 to 49 represent a key life stage where iodine is particularly important for metabolism, healthy growth, and brain development. More than half of UK teenage girls already have inadequate iodine intake before making any dietary switches.
Are organic plant-based milks fortified with iodine?
Organic drinks are not fortified with added nutrients, meaning they are unlikely to provide iodine. Dietitians recommend checking product labels specifically for added iodine and calcium.
Which common foods besides dairy contribute iodine?
White fish such as cod or haddock, as well as eggs, yoghurt, and kefir, can contribute iodine to the diet. Researchers also noted that adding iodised salt to bread helps reduce inadequate intake levels.