Recommendation: Since iodine deficiency is the main cause of simple goiter, it is advisable to eat foods containing iodine, iodized salt, marine fish and aquatic products, and It is also advisable to eat shellfish and seafood, fruits and vegetables rich in vitamins; avoid foods that inhibit the body's absorption of iodine. Patients with simple goiter should avoid eating the following foods. Mustard greens: According to modern research, mustard greens leaves and other vegetables of the mustard genus contain a small amount of goitrogenic substances, which can interfere with the thyroid's absorption and utilization of the trace element iodine. Therefore, people suffering from goiter should avoid eating mustard greens. Cauliflower Commonly known as cauliflower. According to analysis, cauliflower, like other mustard vegetables, contains a small amount of goitrogenic substances. Therefore, people who already suffer from simple goiter should not eat more cauliflower.