Iodine is an essential nutrient for human health, and a deficiency can lead to various health problems. The recommended daily intake of iodine varies by age and sex, but adults typically require 150 micrograms (mcg) per day. Iodized salt is the most common source of iodine in many countries, but iodine deficiency can still occur in some areas due to factors such as limited access or poor nutrition. Excessive intake of iodine can lead to thyroid dysfunction and cancer. The Federal Institute for Risk Assessment (BfR) has developed guidelines for assessing vitamins and minerals in food, including iodine, and provides information on the risks associated with excessive intake.