Women of a certain age who turn to the paleo diet to lose weight should take care, says a recent study – they may be putting themselves at risk of a mild iodine deficiency. The Paleo diet excludes grains, legumes and dairy products, but includes fruits, vegetables, nuts, seeds, eggs, meat, fish and seafood. Although seafood is a good source of iodine, a two-year trial of 49 obese women at the University of Gothenburg in Sweden found those trying to lose weight on the Paleo diet developed a mild iodine deficiency. They were compared with women sticking to a diet lower in protein and fat and higher in carbohydrates, who showed no signs of deficiency. Iodine helps make thyroid hormones, which play a vital role in keeping cells and the metabolic rate healthy – so the researchers recommended iodine supplements for those on a Paleo diet.