Advantages of taking minerals and natural health supplements in diet

Iodine is essentially a trace mineral responsible for the regulation of the small butterfly-shaped thyroid gland located in the front of the neck. Iodine synthesizes thyroxine and tri-iodothyronine, thyroid hormones necessary for normal growth and development in humans and some animals. This relatively small gland, weighing only 15 to 20 g, stores up to 80 percent of all iodine in the body, which translates into 15 mg in the average adult. The remaining stores are found in the blood and muscle tissues and in the ovaries in females.

For the most part, in adults 80 percent of all iodine ingested from food and supplemental sources is ‘trapped’ by the thyroid gland. The ionic form of iodine called iodide, is found naturally in seawater and in the soil. This form is then oxidized by the sunlight and synthesized into iodine. Some iodide is returned to the soil through rain, however much is lost into the atmosphere, resulting in depleted soil concentrations, hence deficient plant sources and then depleted levels in human. To counteract this continuous cycle of depletion, in the 1920s the US government mandated iodine be added to common table salt, a substance widely used in the North American diet, including some sea salts. As a result, iodine deficiency has been almost eradicated in North America. People who live closer to the coastal regions are noted as having higher iodine levels than inland people, especially those living at higher altitudes according to researches.

Although iodine deficiency is rare in developed countries such as the US because crops are commonly grown in iodine-rich soils and table salt has been supplemented with this mineral, it is estimated that 1.6 billion people are still iodine deficient in developing countries. Since the thyroid is known to regulate metabolism, the rate at which we synthesize calories, a deficiency in iodine can result in an slowed metabolism.

Symptoms can start out as dry skin and a hoarse throat, and eventually lead up to an increase in cholesterol levels, reduced mental clarity and delayed reflexes. The most common and telltale sign of an iodine deficiency however, is an enlarged thyroid gland, or a goiter. This condition is caused by a decrease in thyroid hormone levels, a disease known as hypothyroidism. People suffering from this condition often feel fatigued or sluggish, they gain weight very easily and are sensitive to temperatures, often feeling cold much of the time.

Unfortunately, in small children, hypothyroidism can be quite serious and can impede physical growth and mental development. A review of 10 international studies conducted throughout countries known for iodine deficiency, concluded that children who are deficient in iodine all suffer from impaired motor skills, poor dexterity and coordination and diminished muscle strength among other things.

A goiter can result in incidences in which less than 20 mg of iodine per day are ingested. In such situations the thyroid gland eventually hypertrophies, meaning it holds any stores or incoming iodine within the gland itself as a counter measure, realizing concentrations are limited. This results in an enlarged thyroid gland or goiter. Some goiters can be very pronounced while others are less noticeable depending on the degree of the deficiency.

In cases of pregnant women who are iodine deficient themselves, the fetus is at serious risk of cretinism, a condition that causes severe retardation in the physical and mental development of the growing baby. If the iodine deficiency continues and the disease if left untreated, the child’s growth will become permanently stunted, resulting in dwarfism in extreme cases.

Apart from iodine’s obvious use to prevent and treat hypothyroidism, the mineral has also been linked to cases of fibrocystic breasts. Studies suggest that hypothyroidism and iodine deficiencies contribute to the development of the fibrocystic breast tissue that result in tender and painful breasts in women, especially just before menstruation. Certain foods are also shown to worsen the condition such as chocolate, caffeine and fatty foods. Research however, shows that iodine supplements may effectively reduce symptoms of tenderness with very few side effects.¹

Anyone who has ever cut or injured themselves knows the familiar look and smell of iodine as it is painted over the wound. Although quite unpleasant, this distinct, brownish substance is found to reduce infection, inflammation and promote healing.

Iodine is also used in chronic cases of vaginitis, a condition that results in itching, burning, and irritation of the vagina. Iodine used in a douche has been found to improve symptoms of itching and discharge as well as reduce painful inflammation often associated with this condition.²

Many nutritional products advertise iodine as a weight loss stimulant, most likely in relation to the metabolic functions associated with the thyroid gland. Studies to date however do not support the theory that iodine alone is responsible for weight loss or increased energy in healthy people.

In cases of iodine deficiency though, supplementing iodine may bring the body’s iodine levels within normal range, thereby renewing energy and metabolism. Nevertheless, there is no concrete evidence that iodine or products such as seaweed or algae will have the desired effects often touted by manufacturers.

The most common and easily accessible source of iodine is iodized table salt. One teaspoon contains as much as 400 mcg of iodine. Since the RDA is only 150mcg per day it is easy to understand why iodine deficiencies are quite rare in North America. Sea life including plants and animals absorb iodine from the seawater. Shellfish are an excellent source as is kelp (seaweed), algae and deep-water white fish. On land, sources include garlic, soybeans, spinach, Swiss chard, turnip greens, sesame seeds, lima beans and summer squash.

Many commercial baked goods are also a good source of iodine because bakeries often add iodine to the dough in order to stabilize it. Sea kelp tablets are also a very common and a highly concentrated source of iodine. Other secondary and less easily monitored sources include dairy products produced by cows that have grazed on coastal grasses. Fruits and vegetables grown in coastal soils also tend to have higher iodine levels than those grown further inland away from the salty sea water that evaporates into the ground in the coastal regions. It is a fallacy however, that salty processed snacks contain iodine, most of these are simply high sodium foods with no iodine content or nutritional value whatsoever.

The recommended daily allowance for iodine as listed by the FDA is 150 mcg per day. Generally, according to most nutritionist however, 1,5 to 2 mg is adequate to sustain the necessary biological functions associated with iodine. Chronic intakes at 20 times the daily requirement (2 mg/day) are associated with toxicity.

In some areas of Japan especially, many people consume 50 to 80 mg per day of iodine. Reports show that some of these people develop goiters, although most retain normal thyroid functioning. Sudden large doses nevertheless can result in thyroid diseases such as Hashimoto’s disease, chronic inflammation of the thyroid gland often resulting in hyperthyroidism. Grave’s disease, a situation in which the immune system over stimulates the thyroid gland and the oversized gland secretes more hormone leading to hyperthyroidism. some people with Graves' disease may develop exophthalmos (prominent eyes that protrude from the sockets) and edema (swelling) of the legs. The condition hyrotoxicosis, caused by excess thyroxine and tri-iodothyronine, also result in hyperthyroidism and some thyroid cancers. For people in their seventies and eighties, hyperthyroidism is often the result of a thyroid with several nodules or lumps that make too much thyroid hormone. This condition, called Plummer's disease, is often accompanied by apathy, depression, weight loss, and irregular heart-beats. It can also accelerate osteoporosis.

Health professionals strongly caution people, especially those who live in iodine-rich areas, to avoid iodine supplements without first consulting a professional. It is also essential for people using iodine supplements to take regular thyroid function tests to check their thyroid levels.

There are few reports of drug interactions associated with iodine supplements, apart from of course, medications for either hyper or hypothyroidism. The effects of anti-thyroid drugs such as methimazole, used to reduce thyroxine levels, can be reduced by iodine. To the contrary, the effects of drugs such as levothyroxine, used to increase thyroxine levels in cases of hypothyroidism, can be enhanced, often resulting in too much thyroid hormone. Some reports of people taking lithium and using iodine supplements show adverse reactions as well. As with any supplement or herb, it is always best to consult a health professional prior to taking it, especially if you are currently using other medications.

Reference:

1. Ghent WR, Eskin BA, Low DA, Hill LP, “Iodine replacement in fibrocystic disease of the breast”, Can J Surg, Oct 1993; 36:453-460.
2. Nyirjesy P, Weitz MV, Grody MH, Lorber B, “Over-the-counter and alternative medicines in the treatment of chronic vaginal symptoms”, Obstet Gynecol, 1997; 90(1):50-53.