Iodine is a chemical element that is mainly found on Earth as a water-soluble ion, meaning that it tends to concentrate in oceans and saltwater pools. This element – which our bodies cannot make, meaning we need to derive it from food – is perhaps best-known for its role in maintaining thyroid function, which is an extremely important task. In fact, it’s not an exaggeration to say that iodine is needed for the healthy functioning of practically every cell in our bodies. Let’s take a closer look at those functions.
What Iodine Does for Us
Maintains thyroid function – Iodine helps our bodies to produce thyroid hormones, which ensure that our thyroid remains healthy. The thyroid is a large endocrine gland located near the base of the neck that controls how quickly our bodies use energy, create proteins, and regulate hormone sensitivity. An underactive thyroid slows the metabolism, making weight loss difficult. Therefore, a healthy thyroid is the first requisite for a successful weight loss diet.
Promotes physical and mental growth – Iodine is especially important for children because the thyroid hormones it produces are closely related to growth hormones, which are needed for both physical and mental growth. Consequently, an iodine deficiency can result in both physical retardation and the retardation of intelligence and basic skills such as speech, movement, and hearing. These issues also extend towards unborn children; studies at the Linus Pauling Institute, for instance, have shown that an iodine deficiency during pregnancy can cause mental retardation and stunted growth in the baby. Iodine deficiencies have even been shown to increase the risk of stillbirth, miscarriage, and birth defects.
Regulates body temperature – Thyroid hormones help our bodies to dilate our blood vessels, thus allowing warm blood to flow to our extremities. This means that our body temperatures are greatly influenced by our iodine intake. When our iodine levels are comfortable, our cells make more energy, resulting in increased body temperature. Conversely, when our iodine levels are low, our body temperature decreases, and we experience cold hands and feet.
Controls cholesterol and heart rate – The thyroid hormone triiodothyronine (T3) helps us to trigger the breakdown of cholesterol, resulting in reduced cholesterol levels. The T3 hormone also controls our heartbeat rate; too much iodine results in a fast heartbeat, which tires the heart, while too little iodine results in a poor circulation of oxygen, nutrients, and warmth. Ideally, you want your heart to beat at around 72 beats per minute, which is what you’re likely to have if your diet contains good amounts of iodine.
Maintains a healthy emotional state – Since thyroid hormones affect our sensitivity to adrenaline and other endocrine hormones, insufficient thyroid hormone levels (induced by insufficient iodine levels) effectively limits our ability to respond to events in a normal manner. This can lead to lethargy and apathy (the feeling of being “dead inside” can be caused by an iodine deficiency). In some cases, it can trigger full-blown depression.
Recommended Daily Intake
The RDI of iodine for adolescents and adults of both sexes is 150 micrograms per day. Young children (between 1-8 years) should receive 90 micrograms per day, while older children (between 9-13 years) should receive 120 micrograms per day. The RDI of iodine for pregnant women, on the other hand, is 220 micrograms per day, increasing to 270 micrograms per day for breastfeeding women.
Excellent dietary sources of iodine include sea vegetables, fish, baked potatoes, plain yogurt, beans (especially navy, lima, and string beans), and turkey breasts.
About the Author
Michael Ravensthorpe is an independent writer whose research interests include nutrition, alternative medicine, and bushcraft. He is the creator of the website, Spiritfoods, through which he promotes the world’s healthiest foods.