Russians experience fatigue, loss of memory and concentration due to iodine deficiency, said nutritionist and endocrinologist Anton Polyakov. According to him, a deficiency slows the metabolism, leads to weight gain and an enlarged thyroid gland, as well as coldness, swelling, hair loss, thinning eyebrows and mood swings. The body tries to extract more iodine from the blood, the thyroid gland tissue grows, the production of hormones decreases, therefore chronic fatigue appears that is not relieved by rest.