Food to Avoid With Hypothyroidism

Hypothyroidism is a disease characterized by an underactive thyroid gland, which is located at the front of the neck. Low thyroid hormone levels affect body metabolism, which results in serious health problems if not treated, reports Maryland Medical Center. Iodine deficiency is the main cause of hypothyroid, according to David Rakel M.D., Professor at the University of Wisconsin in the book "Integrative Medicine."

Hypothyroidism treatment involves replacing thyroid hormone levels with levothyroxine, and having a diet rich high in antioxidants, B-vitamins and iodine, among other nutrients. Foods that interfere with thyroid function should be avoided, which include Brassica vegetables, soybeans, spinach and cassava, according to Rakel.

Brassica Vegetables

• Brassica is a genus of plants that includes broccoli, cabbage, Brussels sprouts, cauliflower, kale, mustard and turnip greens. People with hypothyroidism should avoid eating these specially if raw, says Rakel. Brassica vegetables have substances called goitrogens, which can reduce the function of the thyroid gland.

Soybeans

• Soybeans and their products, such as tofu, soy flour, soy lecithin and soybean oil, contain the isoflavone genistein. This substance can interfere in the absorption of iodine, already deficient in individuals suffering from hypothyroidism, according to Rakel.

Cassava and Spinach

• Cassava is rich in thiocyanate, a substance that in high quantities can lead to an underactive thyroid gland and cause hypothyroid, reports Rakel. Like cabbage and other Brassica plants, spinach also contains goitrogens, which can affect thyroid function.