Salt Restriction Could Lead to Lack of Iodine in the Body

More Americans are restricting their salt intake, especially those who have heart disease or hypertension - but there may be a side-effect to too much salt restriction. A new study published in the American Journal of Hypertension recently showed that people who lower their salt intake too much may increase their risk of iodine deficiency.

Lack of Iodine: What is the Role of Iodine in the Body?

Iodine has been added to salt since the 1920s to ensure that Americans get adequate iodine in their diet. Lack of iodine in the diet can lead to thyroid dysfunction, because iodine is required for the synthesis of thyroid hormone, a hormone required for cell metabolism - and one that's essential for life.

Lack of thyroid hormone leads to the condition known as hypothyroidism, a relatively common disease associated with symptoms such as excessive fatigue, forgetfulness, constipation, weight gain, mental instability, dry skin and other unpleasant signs and symptoms. Before iodine was added to salt many years ago, enlargement of the thyroid gland - a condition known as goiter - was common in this country.

Researchers looked at data on almost 2,000 men and women to study the relationship between lack of iodine and salt restriction. They found among salt-restrictors, 40% of women were iodine-deficient and 25% of the men had levels of iodine that were too low.

What Does This Mean?

It's still important to cut back on salt if you have a history of heart disease or hypertension, but to reduce the risk of iodine deficiency replace the missing iodine with iodine from other food sources to make up for the loss. Some of the best sources of this important element are sea vegetables, milk, yogurt, strawberries and watercress.

If you experience symptoms of hypothyroidism, see your doctor for thyroid function testing, especially if you're a salt restrictor or have an enlarged thyroid gland.

Talk to your doctor about how much sodium restriction is appropriate for your particular situation. Most doctors recommend that the general public get under 2,300 milligrams per day - and people who have high blood pressure or heart disease should keep their intake to 1,500 milligrams a day or less. If you go that low, add more iodine-rich food sources to your diet to reduce the risk of iodine deficiency - and an underactive thyroid.

References:

Food Navigator-USA.com. "Salt Restriction Could Increase Risk of Iodine Deficiency"

Professional Guide to Diseases. Ninth Edition. 2009.