Thank you, Bernard Courtois, discoverer of iodine. In 1811, after isolating iodine and noticing its distinctive violet hue in vapor form, chemists suggested the name “iode” from the Greek word for violet. Today we know this element as iodine, classified as a halogen on the periodic table, with an atomic number of 53. As with other halogens, it is a potent oxidizing agent, although it’s the weakest oxidizing agent of the stable halogens.
The bottom line is that it’s good at what it does, even though its siblings may do it a bit better. Iodine is the kid who works hard, doesn’t ask for too much allowance, and always ends up on time for supper. He’s great when you need the trash taken out, too.
Iodine, although not as abundant as we’d like it to be, has properties that make it incredibly useful to the body. It binds well to organic compounds as a result of its higher atomic number, and it is necessary for the body to synthesize thyroid hormones. According to the American Thyroid Association, “Iodine is an element that is needed for the production of thyroid hormone. The body does not make iodine, so it is an essential part of your diet.” (1)
How essential? How much iodine do we need daily? The Institute of Medicine has set the Recommended Dietary Allowance (RDA) for iodine in adult men and women at 150 μg per day, although recent studies show that this number should be much higher.
With all this talk about iodine, thyroids, and the like, what are we trying to accomplish? How does iodine benefit the body? What are the benefits of iodine that really matter to the body? Most who even have a cursory knowledge of iodine understand that iodine helps convert thyroid stimulating hormone (TSH) to T3 and T4 (triiodothyronine and thyroxine), aiding and supporting proper thyroid function. But what else can we expect from iodine? (2)
Benefit 1: Energy
It doesn’t take a clinician to notice what iodine can mean energy-wise for those who take it as a supplement. Iodine is well known as an energizer. Why? Iodine is very effective in breaking down both carbohydrates and fats in the system. It accomplishes this by helping the body’s metabolism maintain consistency. By supporting stable metabolic activity, iodine makes your body more efficient at processing and utilizing the minerals and nutrients in your diet while forestalling fat absorption. When your energy levels are up, your body is better suited to activity and better able to be active. You’re able to combat the lethargy that results from slower metabolism. (3)
Benefit 2: Toxin Removal
As noted, iodine has an atomic number of 53. This higher number allows it to bind to toxins very well. This ability extends to bacteria as well. It is useful in pulling some heavy metals, such as mercury and lead, out of the body in addition to its antibacterial abilities. Iodine supports the body in eradicating the bacteria that cause peptic ulcers and other gastrointestinal issues. (4)
Benefit 3: Anti-cancer Agent
As a support to the proper function of the thyroid, iodine has been linked in studies to prevention of thyroid cancer.
Thyroid cancer occurs when cells in your thyroid undergo genetic changes (mutations). The mutations allow the cells to grow and multiply rapidly. The cells also lose the ability to die, as normal cells would. The accumulating abnormal thyroid cells form a tumor. The abnormal cells can invade nearby tissue and spread throughout the body. Because iodine facilitates normal cell life-cycle function, including apoptosis, it can support normal die-off of cells in the thyroid and promote healthy function therein. (5)
Benefit 4: Juvenile Cognitive Development
Studies have shown that severe iodine deficiency during childhood has resulted in numerous physiological and cognitive deficiencies. Giving iodine supplements to children with mild iodine deficiency improves their reasoning abilities and overall cognitive function. For children living in iodine-deficient areas, iodine supplements seem to enhance both physical and mental development. (6)
Benefit 5: Protection from Radioactive Material
Iodine can protect from radiation and radioactive side effects.
Remember Chernobyl? The nuclear accident caused a radioactive cloud to move across many parts of Europe, infecting many with radioactive material and causing significant spikes in thyroid cancer among those exposed. A timely protocol of potassium iodide (KI) could have prevented such an adverse result to this radioactive event. A case in point is what happened in Poland:
“After the 1986 Chernobyl nuclear accident, shifting winds blew a radioactive cloud over Europe. As many as 3,000 people exposed to that radiation developed thyroid cancer over the next 10 years. Most victims had been babies or young children living in Ukraine, Belarus, or Russia at the time of the accident. The region of excess risk extended up to a 200-mile radius from Chernobyl. Poland, immediately adjacent to Belarus and Ukraine, distributed KI to more than 95% of its children within three days of the accident and does not appear to have had an increase in thyroid cancer.” (7)
Although the benefits of iodine are numerous, an iodine deficiency can prevent most, and in some cases all, of these functions from occurring in our bodies. Knowing the symptoms of low iodine can alert you to why you may feel fatigued, cold, and sore, and are struggling with sudden weight gain.
Asking the right questions, like “How do I make sure I’m getting enough iodine?” and “Is it possible to get too much?” is the key to fully understanding this vital mineral. (8)
Symptoms of Low Iodine
Iodine deficiency was a problem for many years (prior to the 1920s) in various areas of the world. In the United States, the Great Lakes, Appalachian, and Northwest regions dealt with this issue, as did most of Canada. Treatment of iodine deficiency by the introduction of iodized salt has virtually eliminated iodine deficiency and the so-called “goiter belt” in these areas. However, many other parts of the world still do not have enough iodine available through diet, and iodine deficiency continues to be an important public health problem. Approximately 40% of the world’s population remains at risk for iodine deficiency. (9)
Iodine deficiencies aren’t only an issue in less-developed parts of the world. Many athletes or those who sweat excessively can have iodine deficiencies merely because they’re not replacing the iodine they’re losing through activity. Although severe iodine deficiencies are rare in the developed world, it can be helpful to know what to look for. Following are several symptoms that may be related to low iodine levels: (10)
- Cold hands and feet
- Dry skin
- Hair loss
- Irregular or heavy periods
- Joint pain
- Memory problems
- Muscle cramps
- Sudden weight gain
- Swollen neck
Although most associate iodine loss with sweat, some can be excreted in urine, too. Additionally, because the thyroid gland stores iodine, iodine deficiencies can lead to enlargement of the thyroid and hypothyroidism. Furthermore, mothers who received inadequate amounts of iodine can be at risk of giving birth to children with intellectual disabilities.
How Do I Get Iodine?
In addition to supplements, many foods offer good amounts of iodine. The great news is that many of these are likely already a part of your diet.
Although many traditional foods–including those you might find at the holiday table, like roasted turkey, cranberry sauce, and baked potatoes—offer good amounts of iodine, several sea-based sources offer prime amounts.
Look for seaweeds like kombu, which is often used as stock bases in soups and stew; or nori, which can be sprinkled on salads or used in wraps or sushi. Always opt for organic seaweed; conventional seaweed often contains disruptive heavy metals.
However, seaweed isn’t the only food with iodine. Here’s a non-exhaustive list of 21 foods that contain iodine:
- Baked potato
- Boiled eggs
- Dried seaweed
- Feijoa (also known as pineapple guava)
- Salmon steak
- Turkey breast
- White bread
Iodine is primarily taken in through the diet, with the recommended amount being around 150 mg per day in adults who are not pregnant or lactating. (11)
Can I Be Taking Too Much Iodine?
Whereas proper amounts of iodine are good, high doses can be dangerous. Those with thyroid problems, hyperthyroidism, and autoimmune diseases can regress with too-high doses. Furthermore, coupled with iodine through seaweed, certain medications and even radiology procedures can put people at an even higher risk. (12)
Keep in Mind
Iodine can be stripped through exposure to halogens like fluoride, chlorine, and bromine. Additionally, certain vegetables in the cabbage family, including brussel sprouts, cauliflower, broccoli, radishes, turnips, kale, and watercress can block iodine absorption. For this reason, be mindful of how often you consume them.
One way to absorb iodine better from the foods you consume is to understand the effect that various cooking methods can have on your iodine absorption. A study published in 2013 in the Journal of Food Science and Technology determined that to avoid iodine loss, you should add salt to food after cooking is complete. (13)
Furthermore, storing iodized salt in humid or hot conditions can degrade the iodine; for this reason, it’s recommended to keep your salt in a pantry away from heat exposure.
Eating high-sodium foods at restaurants, in particular, is not a good way to increase your iodine. Few restaurants use iodized salt, meaning salt consumption can go up without receiving any of the benefits of iodine. Be aware that iodized salt usually contains synthesized iodine, which falls far short of the amount of iodine needed for normal growth and function.
Where you live and the quality of your soil can play a significant role in how much iodine you receive in your diet. More than 100 countries add iodine to salt to help citizens get enough. For this reason, use iodized salt to season your food once cooked, and be sure to emphasize iodine-rich foods, like seaweed. Lastly, iodine supplements may be worth looking into for those who struggle to get enough iodine in their daily diets. (14)