Iodine in biology damage). In areas where there is little iodine in the diet, typically remote inland areas and semi-arid equatorial climates where no marine foods are eaten, iodine deficiency also gives rise to hypothyroidism, the most serious symptoms of which are epidemic goitre (swelling of the thyroid gland), extreme fatigue, mental slowing, depression, weight gain, and low basal body temperatures. The addition of iodine to table salt (so-called iodized salt) has largely eliminated the most severe consequences of iodine deficiency in wealthier nations, but deficiency remains a serious public health problem in the developing world. Iodine deficiency is also a problem in
3-hydroxyacyl-coenzyme A dehydrogenase deficiency fatty acids or partially metabolized fatty acids may build up in tissues and damage the liver, heart, and muscles, causing more serious complications. This condition is inherited in an autosomal recessive pattern, which means two copies of the gene in each cell are altered. Most often, the parents of an individual with an autosomal recessive disorder each carry one copy of the altered gene but do not show signs and symptoms of the disorder. 3-hydroxyacyl-coenzyme A dehydrogenase deficiency 3-hydroxyacyl-coenzyme A dehydrogenase deficiency (HADH deficiency) is a rare condition that prevents the body from converting certain fats to energy, particularly during