How many times have you been told to stop eating so much salt? Reducing salt intake is a good idea if you’re prone towards high blood pressure, but there could be a drawback to getting too little salt in your diet – an iodine deficiency. Fortunately, table salt is fortified with iodine to help reduce the risk of an iodine deficiency. When you remove table salt, you take away the best source of iodine – a mineral that’s essential for good thyroid function.
Iodine in the Body: What Does It Do?
The most important function of iodine is to keep the thyroid functioning properly. Iodine is required to synthesize the two thyroid hormones, T3 and T4, which regulate the metabolism of every cell in the body. Not only that, but they play an important role in how cells use protein, fats, and carbohydrates as energy – and are important for brain development and bone growth. There’s no doubt that thyroid hormones play a critical role in the human body – and without iodine they couldn’t be made. Because of this, it’s not surprising that a deficiency of iodine has far-reaching effects in the human body.
Does Too Little Salt Lead to a Deficiency of Iodine?
Researchers looked at data on almost 2,000 hypertensive men and women who reduced their salt intake to 2,400 milligrams of sodium a day to help control their blood pressure. When they checked iodine levels on these salt restrictors, a whopping 40.4 percent of women and 13.6 percent of men were iodine deficient. The discrepancy in the number of iodine deficient men and women may be explained by the fact that women were better at reducing salt in their diet than men – but women still seem more prone to iodine deficiency when they get too little salt.
Other Problems Associated with a Deficiency of Iodine
In addition to its effects on thyroid function, deficiency of iodine in animals increases the risk of breast cancer and stomach cancer. In adult humans, some studies show a deficiency of iodine predisposes to fibrocystic breast disease – a benign condition where breast tissue forms numerous small cysts. In babies or small children, iodine deficiency is one of the leading causes of mental retardation – due to the impact iodine and thyroid hormone have on brain development. It also plays a role in maintaining a healthy immune system and for preventing miscarriages in pregnant women.
Should You Reduce Your Salt Intake?
If salt is such an important source of iodine, is it still safe to lower your salt intake if you have hypertension? People, especially women, with hypertension who are reducing their salt intake below 2,400 milligrams per day, would do well to eat other iodine-rich foods such as sea kelp, yogurt, cow’s milk, strawberries, mozzarella cheese, shellfish, and eggs. Kelp is one of the best sources of iodine, but some kelp supplements contain arsenic – so don’t overdo it. A single cup of yogurt has more than half of the day’s iodine requirement for women.
Too Little Salt and Deficiency of Iodine: The Bottom Line?
If you have hypertension or heart disease, it’s important not to get more than 2,400 milligrams of sodium per day, and some doctors recommend even less – particularly for heart disease patients. If you reduce salt in your diet, be sure to add more iodine-rich foods and have your doctor check your thyroid function regularly through a blood test.
Food Navigator USA website. “Salt restriction could increase risk of iodine deficiency”
World’s Healthiest Foods website.