An iodine primer 10. July 2012 William Davis (7) What if your diet is perfect--no wheat, no junk carbohydrates like that from corn or sugars, you are physically active--yet you fail to lose weight? Or you hit a plateau after an initial loss? First think iodine.Iodine is an essential nutrient. It is no more optional than, say, celebrating your wedding anniversary or obtaining vitamin C. If you forget to do something nice for your wife on your wedding anniversary, I would fear for your life. If you develop open sores all over your body and your joints fall apart, you could undergo extensive plastic surgery reconstruction and joint replacement . . . or you could just treat the scurvy causing it from lack of vitamin C.Likewise iodine: If you have an iodine deficiency, you experience lower thyroid hormone production, since T3 and T4 thyroid hormones require iodine (the "3" and "4" refer to the number of iodine atoms per thyroid hormone molecule). This leads to lower energy (since the thyroid controls metabolic rate), cold hands and feet (since the thyroid is thermoregulatory, i.e., temperature regulating), and failed weight loss. So iodine deficiency is one of the items on the list of issues to consider if you eliminate wheat with its appetite-stimulating opiate, gliadin, and high-glycemic carbohydrate, amylopectin A, and limit other carbohydrates, yet still fail to lose weight. A perfect diet will not fully overcome the metabolism-limiting effects of an underactive thyroid.Given sufficient time, an enlarged thyroid gland, or goiter, develops, signaling longstanding iodine deficiency. (The treatment? Iodine, of course, not thyroid removal, as many endocrinologists advocate.) Your risk for heart attack, by the way, in the presence of a goiter is increased several-fold. Goiters are becoming increasingly common and I see several each week in my office.Iodine is found in the ocean and thereby anything that comes from the ocean, such as seafood and seaweed. Iodine also leaches into the soil but only does so coastally. It means that crops and livestock grown along the coasts have some quantity of iodine. Humans hunting and foraging along the coast will be sufficient in iodine, while populations migrating inland will not.It also means that foods grown inland do not have iodine. This odd distribution for us land dwelling primates means that goiters are exceptionally common unless iodine is supplemented. Up to 25% of the population can develop goiters without iodine supplementation, a larger percentage experiencing lesser degrees of iodine deficiency without goiter.In 1924, the FDA became aware of the studies that linked goiters to lack of iodine, reversed with iodine supplementation. That's why they passed a regulation encouraging salt manufacturers to add iodine, thought to be an easy and effective means for an uneducated, rural populace to obtain this essential nutrient. Their message: "Use more iodized salt. Keep your family goiter free!" That was actually the slogan on the Morton's iodized salt label, too.It worked. The rampant goiters of the first half of the 20th century disappeared. Iodized salt was declared an incredible public health success story. Use more salt, use more salt.You know the rest. Overuse of salt led to other issues, such as hypertension in genetically susceptible people, water retention, and other conditions of sodium overexposure. The FDA then advises Americans to slash their intake of sodium and salt . . . but make no mention of iodine.So what recurs? Iodine deficiency and goiters. Sure, you eat seafood once or twice per week, maybe even have the nori (sheet seaweed) on your sushi once in a while . . . but that won't do it for most. Maybe you even sneak some iodized salt into your diet, but occasional use is insufficient, especially since the canister of iodized salt only contains iodine for around 4 weeks, given iodine's volatile nature. (Iodized salt did work when everybody in the house salted their food liberally and Mom had to buy a new canister every few weeks.)Iodine deficiency is common and increasing in prevalence, given the widespread avoidance of iodized salt. So what happens when you become iodine deficient? Here's a partial list:--Weight loss is stalled or you gain weight despite your efforts.--Heart disease risk is escalated--Total and LDL cholesterol and triglyceride values increase--Risk of fibrocystic breast disease and possibly breast cancer increase (breast tissue concentrates iodine)--Gingivitis and poor oral health increase (salivary glands concentrate iodine)(Naturopathic doctor Lyn Patrick, ND, has written a very nice summary available here.)So how do you ensure that you obtain sufficient iodine every day? You could, of course, eat something from the ocean every day, such as coastal populations such as the Japanese do. Or you could take an inexpensive iodine supplement. You can get iodine in a multivitamin, multimineral, or iodine drops, tablets, or capsules.What is the dose? Here's where we get very iffy. We know that the Recommended Daily Allowance (RDA), the intake to not have a goiter, is 150 mcg per day for adults (220 mcg for pregnant females, 290 mcg for lactating females). Most supplements therefore contain this quantity.But what if our question is what is the quantity of iodine required for ideal thyroid function and overall health? Ah, that's where the data are sketchy. We know, for instance, that the Japanese obtain somewhere between 3,500 and 13,000 mcg per day (varying widely due to different habits and locations). Are they healthier than us? Yes, quite a bit healthier, though there may be other effects to account for this, such as a culture of less sweet foods and more salty, less wheat consumption, etc. There are advocates in the U.S., such as Dr. David Brownstein in Michigan, who argues that some people benefit by taking doses in the 30,000 to 50,000 mcg per day range (monitored with urinary iodine levels).As is often the case with nutrients, we lack data to help us decide where the truly ideal level of intake lies. So I have been using and advocating intakes of 500 to 1000 mcg per day from iodine capsules, tablets, or drops. A very easy way to get this dose of iodine is in the form of kelp tablets, i.e., dried seaweed, essentially mimicking the natural means of intake that also provides iodine in all its varied forms (iodide, sodium iodate, potassium iodide, potassium iodate, iodinated proteins, etc.) This has worked out well with no ill effects.The only concern with iodine is in people with Hashimoto's thyroiditis or (rarely) an overactive thyroid nodule. Anyone with these conditions should only undertake iodine replacement carefully and under supervision (monitoring thyroid hormone levels).Iodine is inexpensive, safe, and essential to health and weight management. If it were a drug, it would enjoy repeated expensive marketing and a price tag around $150 per month. But it is an essential nutrient that enjoys none of the attention-getting advantages of drugs, and therefore is unlikely to be mentioned by your doctor, yet carries great advantage for helping to maintain overall health.