The conventional wisdom is the vast majority of us get enough iodine in
our diet so we don't have to worry about iodine deficiency. A few years ago
this might have been true because conventional table salt is fortified
with about 40 mcg of iodine per gram and heavens knows, we all ate a
lot of salt.
Today, however, people eat less salt and many of us don't use table salt. Instead we use sea salts or kosher salts which are not fortified, plus many of us eat soy or soy products such as soy protein isolate which is found in processed foods. Soy has been shown to actually inhibit thyroid synthesis. If you eat soy, you need more iodine.
What does iodine do, you may wonder. The answer is iodine stimulates the thyroid gland to manufacture a hormone called thyroxine. This essential hormone regulates metabolism in the efficient burning of calories. In children it regulates growth and development.
A deficiency in iodine leads to a condition called hypothyroidism, the symptoms of which include fatigue, weakness, lethargy, weight gain, depression, memory problems, constipation, dry skin, intolerance to cold, coarse and thinning hair, brittle nails and sometimes a yellowish tint to the skin.
If you have some of these symptoms and are worried about having an iodine deficiency you can ask your doctor to test your iodine levels via a urinalysis test. Or you can order a home testing kit from Medicalhometesting.com for $39.95.
Personally, I don't think I have an iodine deficiency, but hypothyroidism is a very slow developing disease and not one I want to ever deal with. So, as a preventative measure, I take a "super kelp" supplement. Available at most retail or online vitamin outlets, these pills are cheap. I paid less than $5 for 250 daily tablets, which are small and contain 250 mcg of iodine (the RDA is 150 mcg).
A few people report that kelp supplements can aggravate existing thyroid problems so you need to pay attention to any changes you feel if you follow my path by taking kelp supplements. And if you have an immune deficiency you need to check with your doctor first.
My only concern, though, is whether or not 250 mcg's is enough. A Harvard thyroidologist, Dr. Robert Utiger, thinks the RDA should be increased to 300 to 400 mcg.