Iodine is an essential mineral found in seafood, iodized salt and some fruits and vegetables. Excess iodine is normally removed from your body by your kidneys. However, if your kidneys are unhealthy, iodine may build up in your body, resulting in iodine toxicity. People with kidney disease should avoid eating a diet high in iodine.
The primary function of iodine in your body is the production of thyroid hormones. These hormones are essential in regulating energy use and metabolism, particularly the use of your body's energy stores, including body fat. Iodine deficiency in the U.S. and other developed countries is rare, because iodine is added to table salt. According to the Linus Pauling Institute Micronutrient Information Center, the recommended daily intake of iodine for adults is 150 micrograms.
Your kidneys filter waste, including excess minerals such as iodine, from your blood, to produce urine. You have two kidneys that sit against your back, just below your rib cage. As your kidneys become unhealthy, they become less able to filter waste from your blood. Diabetes, high blood pressure, poisons, trauma and other diseases can cause your kidneys to stop functioning at full capacity. Signs of kidney disease include frequent urination, fatigue, loss of appetite, swelling in the hands and feet, muscle cramps, darkened skin and itchy or numb sensations.
According to the University of Maryland Medical Center, iodine intake of more than 2,000 micrograms per day may be toxic, especially in those with kidney disease. Over time, even smaller intake of iodine can lead to iodine toxicity when kidneys are unhealthy. According to the Linus Pauling Institute, symptoms of iodine toxicity include burning in the mouth, throat and stomach in addition to fever, nausea, vomiting, diarrhea, heart irregularities and coma.
Avoiding Excess Iodine
Since the primary dietary source of iodine is table salt, avoid eating salt in excess with kidney disease. Food originating from the ocean, including saltwater fish, shellfish and especially sea vegetables such as seaweed or kelp, are high in iodine and should be limited in the diet of those with kidney disease. Iodine may be added to breads or cereal, though the levels are normally low. Fruits and vegetable may also contain iodine, although the concentration varies widely with soil quality. Raw foods such as soy and cruciferous vegetables such as cabbage and broccoli contain chemicals called goitrogens that may prevent your intestines from absorbing iodine.