Almost 19 million babies globally are at risk of developing brain damage each year due to a lack of sufficient iodine during pregnancy, The Guardian reports. In the first 1,000 days after conception, iodine deficiency can lead to neurological and psychological development difficulties.

Global context: Some countries are at risk of iodine deficiency problems throughout their populations because the mineral isn’t consistently available in the soil. And, while iodized salt is available to 86% of the world’s households, in Burundi, Mali, Madagascar, Mozambique, South Sudan, and Sudan deficiency is prevalent.

• “More broadly, widespread iodine deficiency can diminish the cognitive capital of entire nations, diminishing socio-economic progress, experts claim,” according to The Guardian’s Hannah Summers.
• How soils lose iodine, per the World Health Organization's assessment of iodine deficiency disorders: "The erosion of soils in riverine areas due to loss of vegetation from clearing for agricultural production, overgrazing by livestock, and tree-cutting for firewood results in a continued and increasing loss of iodine from the soil."
• In eastern and southern Africa, 3.9 million newborn babies are unprotected, per a UNICEF and Global Alliance for Improved Nutrition (Gain) report. The rate of coverage is better in south Asia, but because of the high number of births, 4.3 million children are still at risk there.
• Some western European countries, including the UK, are not implementing salt iodization well, according to a senior UNICEF advisor on nutrition, Roland Kupka.

The science: Iodine is needed to create thyroid hormones that aid brain development, per WHO.

Since the 1990s, one solution has been to increase accessibility of iodized salt, for instance, through edible salt tablets that contain sufficient amounts of the mineral.

• The recommendation: To eat 5 grams of salt per day, and to make sure that all salt consumed is iodized. Iodine is contained in grains, eggs, and seafood.