Photograph courtesy Wikimedia
Take a look at statues from Ancient Egypt, Greece, or Rome and you will be surprised at the number who show goiters, enlarged thyroid glands, on the neck. Or take a look at European Renaissance paintings, such as the one above by Dutch artist Rogier van Der Weyden, painted around the year 1435—a goiter figures prominently. (The Renaissance period of paintings, in which attention to human anatomic detail was a particular focus, show many people with obvious goiters.) Goiters have plagued humans for as long as our species has walked the planet. There are parts of the world (e.g., coastal regions) where goiters were rare. There are parts of the world where 100% of the population—everyone—had goiters. In much of the world, such as the American Midwest before the 1920s, it was not uncommon for 20% of the adult population to have goiters, 35% of children.
Goiters were associated with serious health problems. Beyond the disfigurement (not just a lump, but sometimes softball-, or even basketball-, sized neck masses), local compressive effects could occur, such as on the airway. Hypothyroidism invariably accompanied the goiter that got worse over time leading to massive water retention, edema, congestive heart failure, breathlessness, crippling fatigue, deafness, a collection of phenomena labeled “myxedema.” The disease would then result in coma, “myxedema coma,” and then, finally, death. If a pregnant woman had a goiter, there was high likelihood of delivering a mentally-impaired child. Goiter, hypothyroidism, myxedema, and impaired mental capacity were therefore huge public health problems all throughout human history, even depicted in works of art.
We now know, of course, that most cases of goiters are due to lack of the micronutrient, iodine. There are Chinese accounts dating back to 2700 B.C., descriptions by ancient physicians such as Hippocrates or Galen, describing relief from goiters with consumption of seaweed or seafood. But this was not proven scientifically until the 1920s when a doctor in Cleveland, Ohio administered iodine tablets to children who experienced regression or disappearance of their goiters.
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. Sadly, most of my colleagues, like health agencies, have forgotten about iodine, even advising their patients that “Iodine is unnecessary,” or “You get enough iodine from diet.”
Given sufficient time, a goiter develops, signaling longstanding iodine deficiency. (The treatment? Iodine, of course, not thyroid removal, as some endocrinologists advocate.) Your risk for heart attack, by the way, in the presence of a goiter is increased several-fold.
Iodine is found in the ocean and thereby anything that comes from the ocean, such as seafood and seaweed, contains iodine. Iodine also leaches into the soil but only does so coastally, lesser quantities evaporating into the atmosphere and then falling to the earth via precipitation. It means that crops and livestock grown along the coasts have some quantity of iodine. Humans hunting and foraging along the coast will usually obtain sufficient in iodine, while populations living inland are less and less likely to obtain iodine, the farther from the ocean they are.
In 1924, the FDA became aware of the studies that linked goiters to lack of iodine, reversed with iodine supplementation. They therefore 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. 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. There have been estimates of a nationwide increase in IQ of 15 points, along with the disappearance of goiters.
You may know the rest of the story. Advice to cut fat intake and include more grains, coupled with the proliferation of processed foods, led to insulin resistance that, in turn, causes sodium retention by the kidneys. Rather than blame their misguided dietary advice, health agencies blamed the use of salt. The FDA and other agencies then advised 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 increases
- Risk of fibrocystic breast disease and possibly breast cancer increase (breast tissue concentrates iodine)
- Gingivitis and poor oral health increase (salivary glands concentrate iodine)
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 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, less wheat consumption, inclusion of fermented foods, etc. There is also more iodine toxicity in Japan. A sign of taking too much iodine is the common blood test, thyroid-stimulating hormone, or TSH. If TSH rises, it suggests that you are getting too much iodine. This phenomenon starts at 750 mcg/day, becomes worse at 1500, 2500, and higher doses.
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 advocating intakes of around 300-350 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. It is a perfect example of old lessons having to be relearned.
