Iodine Supplements May Be Too Much of a Good Thing
June 29, 2013
By Dr. Mercola
The American Thyroid Association (ATA) has issued a statement warning about the risks of too much iodine, especially from iodine, potassium iodide and kelp supplements.1
According to the ATA, such supplements may “contain iodine in amounts that are up to several thousand times higher than the daily Tolerable Upper Limits for iodine.”
They advised against the ingestion of iodine or kelp supplements containing in excess of 500 mcg iodine daily, and noted that ingesting more than 1,100 mcg of iodine per day (the tolerable upper limit) may cause thyroid dysfunction.
Why You Might Only Need High Dose Iodine Supplements in the Event of a Nuclear Disaster
Iodine is a vitally important nutrient that is detected in every organ and tissue and many if not most are deficient in this nutrient. Along with being essential for healthy thyroid function and efficient metabolism, there is increasing evidence that low iodine is related to numerous diseases, including cancer.
There are potentially serious risks to taking too much iodine, however, which is why I generally do not advise taking iodine supplements like Lugol's or Ioderol. Your thyroid only transports iodine in its ionized form (i.e. iodide).
Your thyroid reduces iodide (I-) into iodine (I2) for use in formation of thyroglobulin. Your body doesn't utilize iodine directly. It has to split the I2 into two I- ions, which is an oxidative reaction that causes oxidative stress.
Further, taking too much iodine may also lead to subclinical hypothyroidism, which occurs when your thyroid produces too little thyroid hormone. It’s an ironic association, since hypothyroidism is often linked to iodine deficiency,
But research published in the American Journal of Clinical Nutrition2 revealed that study participants taking relatively higher doses of supplemental iodine — 400 micrograms a day and more – paradoxically began developing subclinical hypothyroidism.
I would recommend taking a large dose iodine supplement in the event of some type of nuclear fallout. In this case, if you're iodine deficient, taking a potassium iodide (a stable form of iodine) supplement can protect your thyroid by "flooding" your system with iodine so your thyroid has no need to take in the radioactive form.
Iodine Is Not Only for Your Thyroid
Though thyroid health is often what people think of when they think of iodine, other tissues also absorb and use large amounts of iodine, including:
||Cerebral spinal fluid
Iodine deficiency, or insufficiency, in any of these tissues will lead to dysfunction of that tissue. Hence the following symptoms could provide clues that you’re not getting enough iodine in your diet. For example, iodine deficiency in:
- Salivary glands = inability to produce saliva, producing dry mouth
- Skin = dry skin, and lack of sweating. Three to four weeks of iodine supplementation will typically reverse this symptom, allowing your body to sweat normally again
- Brain = reduced alertness and lowered IQ
- Muscles = nodules, scar tissue, pain, fibrosis, fibromyalgia
Iodine actually induces apoptosis as well, meaning it causes cancer cells to self-destruct. Dr. Jorge Flechas, MD is adamant that absence of iodine in a cell is what causes cancer, and statistics tend to support this view. Unfortunately, iodine levels have significantly dropped in the United States in recent decades due to several factors, including:
- Bromine exposure: When you ingest or absorb bromine (found in baked goods, plastics, soft drinks, medications, pesticides and more), it displaces iodine, and this iodine deficiency leads to an increased risk for cancer of the breast, thyroid gland, ovary and prostate -- cancers that we see at alarmingly high rates today
- Declining consumption of iodine-rich foods, such as iodized salt, eggs, fish, and sea vegetables
- Soil depletion
- Less use of iodide in the food and agricultural industry
- Fluoridated drinking water
- Rocket fuel (perchlorate) contamination in food
Are 95% of Americans Iodine Deficient?
Worldwide, it's thought that up to 40 percent of the population is at risk of iodine deficiency. In the US, however, agencies tend to say most people are iodine "sufficient," meaning they get enough of the nutrient from their diet. This is controversial, though, as according to other sources, such as Dr. David Brownstein, who has been working with iodine for the last two decades, over 95 percent of the patients in his clinic are iodine deficient.
Dr. Flechas also insists severe iodine deficiency is rampant and believes the current US daily recommended allowance (RDA) for iodine may be completely insufficient for overall physical health and prevention of diseases such as thyroid disease, fibromyalgia and cancer. It is important to realize that the RDA for iodine is not in milligram doses but in micrograms:
- 150 micrograms (mcg) per day for adult men and women
- 220 mcg for pregnant women
- 290 mcg for lactating/breastfeeding women
Dr. Flechas recommends 12.5 milligrams (mg)/day, especially for his pregnant patients to optimize their child’s intelligence, and states that researchers have determined the average dietary intake of iodine for Japanese women is 13.8 mg per day (the Japanese consume far more iodine than Americans due to their daily consumption of sea vegetables). Although he makes a compelling argument, I am not yet convinced that such large amounts may be necessary, so I would encourage you to do your own research, and adopt a sensible, middle-of-the-road approach when it comes to iodine.
Personally, like the ATA, I believe caution may be appropriate here before swallowing milligram amounts of iodine on a regular basis, as we need more research to determine the health effects of too much iodine. I am not yet convinced that high doses are necessary and do not take such large amounts in supplemental form. I do not believe this makes me “iodophobic” as clinicians like Dr. Brownstein accuse me of being. But rather I believe it is wise to exercise caution when using supplemental nutrients. I have reviewed Brownstein’s work and although he has many good points I disagree with his therapeutic recommendations.
How to Increase Your Iodine Levels Naturally
The jury is still out on whether iodine in supplemental form is safe (especially at higher doses). As an alternative, toxin-free sea vegetables and spirulina are likely the ideal natural sources from which to obtain your iodine—however, make sure that these are harvested from uncontaminated waters. Raw milk and eggs contain iodine, as well. At the same time, you'll want to avoid all sources of bromine as much as possible, as this appears to play a large role in the rising levels of iodine deficiency. Here are several strategies you can use to avoid bromine and thereby help optimize your iodine levels naturally:
- Eat organic as often as possible. Wash all produce thoroughly to minimize your pesticide exposure.
- Avoid eating or drinking from (or storing food and water in) plastic containers. Use glass and safe ceramic vessels.
- Look for organic whole-grain breads and flour. Grind you own grain, if possible. Look for the "no bromine" or "bromine-free" label on commercial baked goods.
- Avoid sodas. Drink natural, filtered water instead.
- If you own a hot tub, look into an ozone purification system. Such systems make it possible to keep the water clean with minimal chemical treatments.
- Look for personal care products that are as chemical-free as possible. Remember -- anything going on you, goes in you.
- When in a car or a building, open windows as often as possible, preferably on opposing sides of the space for cross ventilation. Utilize fans to circulate the air. Chemical pollutants are in much higher concentrations inside buildings (and cars) than outside.
Simple Tests for Iodine Deficiency
If you are interested in being tested for iodine deficiency, ask your health care provider about the urine iodine challenge test. Another simple way to ensure you're getting enough iodine is to get an inexpensive prescription from your physician for SSKI, which is a super-saturated potassium iodine. You simply apply three drops to your skin and rub it in, once a day. If when you touch something with slightly wet fingertips it leaves a yellowish stain, then the iodine is coming out of your skin, indicating your body is saturated, i.e. you're getting enough iodine.