Dized salt is a form of table salt which has had iodine added to it to prevent a disease called goiter. goiter is characterized by the swelling of the thyroid gland due to iodine deficiency. Iodine is a nutrient that usually occurs naturally in vegetables, which absorb it from the soil in which they grow. But a diet consisting of food grown in soil that lacks iodine can cause an iodine deficiency, leading to goiter.