Is Iodine the Secret to Healing and Weight Loss? — The Great Iodine Debate_Featured_, Health-Wellness Thursday, August 9th, 2012
By Sally Fallon Morell
(The Weston A. Price Foundation) Iodine is critical to human health. It forms the basis of thyroid hormones and plays many other roles in human biochemistry. While the thyroid gland contains the body’s highest concentration of iodine, the salivary glands, brain, cerebrospinal fluid, gastric mucosea, breasts, ovaries and a part of the eye also concentrate iodine. In the brain, iodine is found in the choroid plexus, the area on the ventricles of the brain where cerebrospinal fluid (CSF) is produced, and in the substantia nigra, an area associated with Parkinson’s disease.
Iodine is essential to normal growth and development. Iodine deficiency in utero and during growth can result in cretinism, a condition of severely stunted physical and mental growth due to prolonged nutritional deficiency of iodine or from untreated congenital deficiency of thyroid hormones (hypothyroidism). The condition is characterized by short stature, delayed bone maturation and puberty, infertility, neurological impairment and cognitive impairment ranging from mild to severe. Iodine deficiency also causes goiter, the gradual enlargement of the thyroid gland. Both conditions have led to public health campaigns of iodine administration in many countries. The addition of iodine compounds to table salt or water represents the first attempt to provide nutrient supplementation via “fortification” of common foods.
Iodine in Public Health Campaigns
In the past, endemic cretinism due to iodine deficiency was especially common in areas of southern Europe around the Alps. It was described by ancient Roman writers and often depicted by medieval artists. The earliest Alpine mountain climbers sometimes came upon whole villages of cretins. In the late eighteenth and early nineteenth centuries, several travellers and physicians described alpine cretinism from a medical perspective, often attributing the cause to “stagnant air” in mountain valleys or “bad water.”
More mildly affected inland areas of Europe and North America in the nineteenth century were referred to as “goiter belts.” The degree of iodine deficiency was milder and manifested primarily as thyroid enlargement rather than severe mental and physical impairment. In Switzerland, where the soil is poor in iodine, cases of cretinism were abundant and even considered hereditary. As the variety of food sources dramatically increased in Europe and North America and the populations became less completely dependent on locally grown food, the prevalence of endemic goiter diminished.
Only in the early twentieth century did scientists discover the relationship of cretinism with lack of iodine and thyroid deficiency. The addition of iodine to salt or drinking water is credited with the reduction or elimination of cretinism and goiter, although cretinism still remains a serious problem in many rural sections of China.
In coastal areas, the action of ocean waves makes iodine gas. Once airborne, iodine combines with water or air and enters the soil. Plant and animal foods grown on soil containing iodine will take up iodine so that it becomes available in the food. It can also be absorbed through the skin from air in seacoast areas, which may explain why many report improved health after a visit to an oceanside resort, and why individuals with severe allergies to iodine risk a reaction if they venture too close to the sea.
Iodine and Breast Health
Japanese women have very low rates of breast cancer and consume high levels of iodine. This observation has led to the theory that high iodine levels in the Japanese diet, rich in seaweed and seafood, provide protection against breast cancer and other diseases of the breast. Proponents of this theory note that today one in seven American women (almost 15 percent) will develop breast cancer during her lifetime. Thirty years ago, when iodine consumption was twice as high as it is now (480 mcg per day) one in twenty women developed breast cancer. Thirty years ago, consumption of iodized salt was higher than it is today; in addition a form of iodine was used as a dough conditioner in making bread, and each slice of bread contained 0.14 mg of iodine. In 1980, bread makers started using bromide as a conditioner instead, which competes with iodine for absorption into the thyroid gland and other tissues in the body. Iodine was also more widely used in the dairy industry as a teat cleaner thirty years ago than it is now. According to this argument, 15 percent of the U.S. adult female population suffers from moderate to severe iodine deficiency.1
The correlation of iodine deficiency with breast cancer is strengthened by reports in the scientific literature. Women with a history of breast cancer are almost three times more likely to develop thyroid cancer than women with no such history, and there is a geographic correlation between the incidence of goiter and breast cancer.2 Demographic studies show that a high intake of iodine is associated with a low incidence of breast cancer, and a low intake with a high incidence of breast cancer.3
Animal studies show that iodine prevents breast cancer, arguing for a causal association in these epidemiological findings. The carcinogens nitrosomethylurea and DMBA cause breast cancer in more than 70 percent of female rats. Those given iodine, especially in its molecular form as I2, have a statistically significant decrease in the incidence of cancer.4 Other evidence adding biologic plausibility to the hypothesis that iodine prevents breast cancer includes the finding that the ductal cells in the breast, the ones most likely to become cancerous, are equipped with an iodine pump (the sodium iodine symporter, the same one that the thyroid gland has) to soak up this element.5
Similar findings apply to fibrocystic disease of the breast. In animal studies, female rats fed an iodine-free diet develop fibrocystic changes in their breasts, and iodine in its elemental form (I2) cures it.6
As far back as 1966, Russian researchers showed that iodine effectively relieves signs and symptoms of fibrocystic breast disease. Seventy-one percent of 167 women suffering from fibrocystic disease experienced a beneficial healing effect when treated with 50 mg potassium iodide during the intermenstrual period.7
A 1993 Canadian study likewise found that iodine relieves signs and symptoms of fibrocystic breast disease in 70 percent of patients. This report is a composite of three clinical studies, two case series done in Canada of 696 women treated with various types of iodine, and one in Seattle. The Seattle study was a randomized, double-blind, placebo-controlled trial of 56 women designed to compare 3-5 mg of elemental iodine (I2) to a placebo (an aqueous mixture of brown vegetable dye with quinine). Investigators followed the women for six months and tracked subjective and objective changes in their fibrocystic disease.8
An analysis of the Seattle study showed that iodine had a highly statistically significant beneficial effect on fibrocystic disease. Iodine reduced breat tenderness, nodularity, fibrosis, turgidity and number of macrocysts compared to controls. This 36-page report9 was submitted to the Food and Drug Administration (FDA) in 1995, seeking the agency’s approval to carry out a larger randomized controlled clinical trial on iodine for treating fibrocystic breast disease. FDA declined to approve the study, because “iodine is a natural substance, not a drug.” But the FDA has now decided to approve a similar trial sponsored by Symbollon Pharmaceuticals.
Iodine may be helpful in treating other cancers because it induces apoptosis, programmed cell death. Apoptosis is essential to growth and development (fingers form in the fetus by apoptosis of the tissue between them) and for destroying cells that represent a threat to the integrity of the organism, like cancer cells and cells infected with viruses. In one experiment, human lung cancer cells with genes spliced into them that enhance iodine uptake and utilization underwent apoptosis and shrank when given iodine, both when grown in vitro outside the body and implanted in mice.10 Some practitioners predict a wider use for iodine in treating cancer.
Iodine may have other benefits – for which more study is needed. Evidence indicates that increased iodine consumption replaces and therefore helps detox other halogens, such as fluoride and bromide, and even toxic metals like lead, aluminum and mercury.11 One theory is that liberal amounts of iodine in the diet can protect against the harmful effects of fluoridated water.12 Iodine supports the immune system and protects against abnormal growth of bacteria in the stomach.13
In addition to the thyroid and mammary glands, other tissues possess an iodine pump (the sodium-iodine symporter) which allows iodine concentration. Thus, it is logical to conclude that iodine plays an important role in these organs—the stomach mucosa, salivary glands, ovaries, thymus gland, skin, brain, joints, arteries and bone.
A History of Iodine Therapy
Iodine was discovered in 1811 and shortly thereafter entered the materia medica. It was used in large amounts until the mid-1900s for treating various dermatologic conditions, chronic lung disease, fungal infestations, tertiary syphilis and even arteriosclerosis.14 The Nobel laureate Dr. Albert Szent Györgi (1893-1986), the physician who discovered vitamin C, wrote: “When I was a medical student, iodine in the form of KI [potassium iodide] was the universal medicine. Nobody knew what it did, but it did something and did something good. We students used to sum up the situation in this little rhyme:
If ye don’t know where, what, and why Prescribe ye then K and I.”15
According to the 11th edition of the Encyclopedia Britannica, published in 1911, the pharmacological action of compounds containing potassium iodide, “is as obscure as their effects in certain diseased conditions are consistently brilliant. Our ignorance of their mode of action is cloaked by the term deobstruent, which implies that they possess the power of driving out impurities from the blood and tissues. Most notably is this the case with the poisonous products of syphilis. In its tertiary stage—and also earlier—this disease yields in the most rapid and unmistakable fashion to iodides, so much so that the administration of these salts is at present the best means of determining whether, for instance, a cranial tumor be syphilitic or not.” (Perhaps what the iodides did was remove toxic mercury from the bodies of syphilitics who had been treated with mercury-based medicines!)
Sarah Pope, our Tampa/St. Petersburg chapter leader, reports that her father, a pediatrician, routinely gave Lugol’s solution (a combination of iodine and potassium iodide) to treat congestion in the lungs and sinuses. The theory was that the iodide drops would thin the mucus and make coughing more productive. The dose was five drops in water, continued for several days. In his professional experience, the remedy cleared congestion and, in the case of asthmatics, dilated the bronchial tubes and assisted breathing. This author received the same remedy as a child—the taste of iodine brings back memories of being sick and in bed, and receiving the drops in orange juice.
The decline in the use of iodine in medicine began in 1948 when researchers Wolff and Chaikoff published a landmark paper on the thyroid effects of increasing amounts of potassium iodide, injected into rats. The authors stated: “Organic binding of iodine within the glands can be almost completely blocked by raising the level of plasma inorganic iodine (PII) above a certain critical level, which for the rat amounts to about 20 to 35 percent.”16 This effect became known as the Wolff-Chaikoff (W-C) effect. According to the conventional view, high levels of intracellular iodide suppress the transcription of thyroid peroxidase (TPO) enzyme, along with NADPH oxidase, leading to a reduction in the synthesis of thyroid hormone, thyroxin.17 As proof of the W-C effect, the textbooks point to the fact that large amounts of potassium iodide can remedy hyperthyroidism. Another apparent confirmation is the thyroid-suppressing effect of several iodine-containing drugs, of which the most famous is amiodarone, which can cause both under- and overactivity of the thyroid. In a trial that compared amiodarone with other medications for the treatment of atrial fibrillation, biochemical hypothyroidism (as defined by a TSH level of 4.5-10 mU/L) occurred in 25.8 percent of the amiodarone-treated group as opposed to 6.6 percent of the control group (taking placebo or sotalol). Overt hypothyroidism (defined as TSH greater than 10 mU/L) occurred at 5.0 percent compared to 0.3 percent.18
Over time, these observations led to a decline in the use of iodine in medicine. While health officials came to a general agreement that iodine deficiency caused, in increasing order of severity, goiter and hypothyroidism, mental retardation and cretinism, authorities in the U.S. and Europe agreed upon a low Reference Daily Intake (RDI), formerly called the Recommended Dietary Allowance (RDA), of 100-150 mcg per day. This amount will prevent goiters and other overt signs of deficiency but may not be adequate to prevent other conditions of iodine deficiency, and is much lower that the amounts formerly given routinely to patients.
Critics of the W-C effect note that the standard dose of potassium iodide was 1 gram until the mid-1900s, which contains 770 mg of iodine, over five thousand times more than the RDI. For many years physicians used potassium iodide in doses starting at 1.5 to 3 gm and up to more than 10 grams a day, on and off, to treat bronchial asthma and chronic obstructive pulmonary disease, apparently with good results and few side effects. Even today, dermatologists treat certain skin conditions, including fungal eruptions, beginning with an iodine dose of 900 mg a day, followed by weekly increases up to 6 grams a day as tolerated.
But the general use of iodine and iodine compounds in medicine has waned, as has its use as an additive in the food supply. Today’s medical establishment is wary of iodine as are public health officials. Thyroidologists cite the W-C effect and warn that TSH (thyroid stimulating hormone) blood levels can rise with an iodine intake of one milligram or more.
In a 2000 review paper on use of iodine as a water disinfectant, author Joe Hollowell notes that studies indicate marked individual sensitivity to iodine; the most vulnerable to adverse effects are those with underlying thyroid disease and previous low iodine intake. Problems from consumption of iodized water—including both hypothyroidism and hyperthyroidism—usually resolve after consumption is discontinued. A safe dose is 1-2 grams per day, and most can tolerate much higher amounts without problems.19