KATHY O'CONNOR-WRAY, Special to The Sun Published Nov. 23, 2018

https://www.jacksonsun.com/story/news/local/2018/11/23/iodine-deficiency-silent-epidemic/2092148002/

In the developed world, iodine deficiency has increased more than fourfold over the past 40 years. Nearly 74 percent of normal, “healthy” adults may no longer consume enough iodine. Coupled with the trend of reduced salt consumption, the increase in non-iodized salt and use of more sea salt (which doesn’t usually have iodine added), there is now an increase in the number of people being diagnosed with iodine deficiency. An article published in The American Association of Clinical Endocrinologists discusses the decreased intake of iodine by 50 percent since the 1970’s and the reemergence of mild iodine deficiency.

Why is iodine so important?

Although we only need a small amount, iodine plays many important roles in the body. It’s used by cells to covert food into energy and also needed in order for your thyroid to function properly and produce just the right amount of hormones. Thyroid hormones are essential for both children and adults, assisting in growth, brain development, reproductive health, and metabolism. This development starts in utero, which is why it is critical pregnant women receive adequate amounts.

Signs of iodine deficiency

The Centers for Disease Control (CDC) has reported that iodine deficiency is one of the four major deficiency diseases in the world. Symptoms of deficiency can include enlargement of the thyroid gland, also known as a goiter, fatigue, constipation, unexpected weight gain, hair loss and sensitivity to cold temperatures. There are all the symptoms you’d also find with hypothyroidism (low thyroid hormones) since iodine is used to make thyroid hormones.

While goiter was relatively common a few generations ago, most middle age and younger Americans have never seen it. This is largely due to the industry practice of salt iodization in this country, first implemented in the 1920s after the effects of iodine deficiency were recognized and since emulated around the world. The Morton company was the first to add iodine to salt in 1924, after a successful public health campaign. Unfortunately, as evidenced by recent FDA findings, many table salt makers are now failing to add iodine in quantities sufficient enough to support optimal health.

Iodine deficiency can be especially dangerous when you’re pregnant or in children since it can affect brain development and reproductive health. Since iodine isn’t naturally found in many foods, cutting iodized salt out of your diet could be leaving you falling short of this essential nutrient.

The emerging role of iodine in breast health

Iodine deficiency is rapidly emerging as a major risk factor for breast cancer. Human breast tissue and breast milk contain higher concentrations of iodine than the thyroid gland itself, which contains just 30% of the body’s iodine stores. Breast tissue is rich in the same iodine-transporting proteins used by the thyroid gland to take up iodine from the blood.

Iodine plays an important role in the health of women’s breast tissue. In the presence of chemicals and enzymes found in breast tissue, iodine has been shown to exert a powerful antioxidant effect equivalent to vitamin C. Iodine-deficient breast tissue exhibits chemical markers of elevated lipid peroxidation, one of the earliest factors in cancer development. Iodine-deficient breast tissue also shows alterations in DNA and increases in estrogen receptor proteins. Coupled with iodine deficiency-induced increases in circulating estrogen levels, these changes can substantially increase the risk of breast cancer in women with low iodine levels. Studies of iodine therapy for breast cancer prevention are encouraging.

In addition to its obvious role in preventing breast cancer, increased iodine intake may be important in mitigating another common painful breast disorder - fibrocystic breast disease.While harmless, fibrocystic breast disease is extremely common and very painful. It is found in at least 9 percent of all women who undergo biopsies, though the actual rate is probably much higher. Animal studies have shown that fibrocystic breast disease can be induced by depriving breast tissue of iodine. These changes can be reversed by iodine doses equivalent to 5,000 mcg per day in humans. Women with fibrocystic breast disease obtain substantial relief from oral administration of iodine at doses of 3,000-6,000 mcg, with 65 percent achieving improvements according to their own and their healthcare provider’s assessments. It is becoming increasingly clear that iodine deficiency interferes with optimum breast health, and intake of levels far higher than the recommended dietary allowance are required to achieve benefits. Daily amounts of 3,000-6,000 mcg may help relieve the symptoms of fibrocystic breast disease.

The role of iodine in cardiovascular health

Iodine and iodine-rich foods enjoy a long history as natural therapies for hypertension and cardiovascular disease. Even when no overt symptoms are evident, hypothyroidism can contribute to heart disease and stroke, and it increases the risk of death from these conditions. Thyroid dysfunction creates unfavorable disturbances in lipid profiles, elevating low-density lipoprotein (LDL) and total cholesterol levels and raising the risk of atherosclerosis. Hypothyroidism also weakens the heart muscle, causing it to “squeeze” less firmly with each contraction; it can cause cardiac arrhythmias as well. These effects may not be evident at rest but become important during moderate exercise. Low thyroid function is also associated with higher waist-to-hip ratios, an obesity-related risk factor for cardiovascular disease.

Restoring normal thyroid function helps reverse multiple cardiovascular risk factors, most notably adverse lipid profiles. Yet mainstream medicine has traditionally used thyroid hormone treatment, which may be dangerous if it over-drives an already weakened heart. Iodine therapy shows promise in safely and effectively modulating these health concerns.

Iodine protects against stomach cancer

The thyroid gland, breast tissue, and portions of the digestive tract share similarities in that all of them contain a rich concentration of iodine. Stomach lining cells concentrate iodine, capitalizing on its antioxidant effects. This has led medical researchers to investigate whether iodine deficiency plays a role in cancers of the digestive tract. They found that people living in iodine-deficient areas of the world are not only prone to iodine-deficiency goiters, but also have higher rates of stomach cancers. Gastric cancer is the most common cancer in parts of northeastern Turkey where iodine deficiency is common, and iodine levels in gastric cancer tissue were markedly lower than those in surrounding healthy tissue. Increased iodine intake has been strongly correlated with a reduction in stomach cancer rates in recent years.

Iodine is critical to healthy thyroid function. Its deficiency can cause weight gain, low energy, depression, cardiovascular disease, cognitive decline, and a variety of cancers. Yet rates of iodine deficiency have reached epidemic levels. Recent scientific analysis reveals that many commercial table salt brands now contain inadequate amounts of iodine. Emerging evidence points to the severe impact of low iodine on a wide range of health issues, including increased risks of breast cancer and fibrocystic breast diseases.