By Martin Feldman, M.D., and Gary Null, Ph.D.
REBALANCING THE THYROID SYSTEM
Conventional medicine’s view of thyroid functioning is marked by two distinct problems:
- One problem, as noted in Part 1 of this article, is the flawed process of diagnosing thyroid disorders. Even when a patient is obviously symptomatic, his or her condition may go unrecognized by orthodox physicians because they focus so exclusively on the results of conventional thyroid blood tests. These tests do not directly measure the functioning of the entire thyroid system, which includes both the central production of T4 hormone and the conversion of T4 to T3 at the tissue level. This conversion process, which occurs outside of the thyroid gland itself, is essential because T3 is the active form of thyroid hormone that works in the body’s cells.
- The second problem with the mainstream approach to thyroid functioning occurs in the treatment phase. When a patient is in fact diagnosed with a low thyroid condition by conventional medicine, the physician’s automatic, reflex reaction generally is to prescribe a synthetic T4 medication that does not contain T3.
The use of thyroid medication may be the easiest path for doctor and patient alike, but it is not the best long-term solution for a suboptimal thyroid system. A preferable (and more natural) approach is to help the thyroid mechanism heal itself using a variety of nondrug treatments. This healing process may reset the full functioning of the thyroid system, whether the central thyroid thermostat, which produces T4, or the peripheral conversion of T4 to T3. As a result, the patient will not have to depend on an oral thyroid hormone medication to function optimally.
In Dr. Feldman’s experience, when a patient takes thyroid hormone medication for months on end, the thyroid system recognizes that it no longer needs to produce thyroid hormone internally and shuts itself down. The result is that the patient stays on the drug for many years or even for life. Therefore, when patients are amenable to a natural rebalancing, Dr. Feldman prefers to try to repair and optimize the thyroid system without medication. This process requires a two- to three-month therapeutic trial.
A NATURAL PROTOCOL FOR REPAIR
The effectiveness of the natural repair process is partly determined by the patient’s level of commitment. The more changes you are willing to make, the higher your probability of success in rebalancing the thyroid system.
The specific steps involved fall into two main categories: lifestyle changes and natural therapies that support thyroid functioning. They are as follows:
1. DETOXIFY AND CLEANSE THE BODY
Any toxins in your system may have a negative effect on thyroid functioning, so it’s important to reduce your exposure to toxins such as fluoride, chlorine, mercury, pesticides, aspartame and caffeine. Patients with a suboptimal thyroid system need to clean out the toxins that have been accumulating in the body.
In Thyroid Power: Ten Steps to Total Health, authors Richard Shames, M.D., and Karilee Shames, R.N., Ph.D, note that the “everyday legal drugs” of caffeine, alcohol, tobacco and even sugar are especially harmful to thyroid function. Nicotine, in particular, hinders the conversion of T4 hormone to T3, while the others have a more indirect effect.[i]
The Shameses also believe that the multitude of chemicals found in our food, water and air are largely responsible for today’s epidemic of thyroid conditions. These chemicals are hormone disrupters that can confuse and stress the immune system, leading to an autoimmune process that attacks the thyroid system. Other investigators agree that synthetic chemicals often interfere with the thyroid hormone balance. [ii], [iii]
Of the many types of hormone disrupters that exist today, the main culprits worldwide seem to be pesticides. Herbicides, fungicides, insecticides and nematocides often contain PCBs (polychlorinated biphenyls) and dioxins, both of which have a wide range of disruptive effects. These effects have been documented, but there are many other synthetic chemicals polluting the environment that have not been well studied.[iv]
As you detoxify your body, consider whether your diet also may be impairing your thyroid functioning. An excess intake of carbohydrates, for example, can be a major contributing factor in hypothyroidism because it can push the blood sugar high and stimulate the production of cortisol. This leads to hypoglycemia and interferes with thyroid production.[v]
2. USE A FLUORIDE FILTER
The incidence of hypothyroidism is higher among people who drink fluoridated water without using a filter, according to Dr. Feldman’s patient records. The reason for this connection is not entirely clear, but it may be that the fluoride and thyroid molecules are similar in chemistry. As a result, fluoride poisoning seems to target the thyroid.
People with thyroid problems would do well to avoid fluoride, which actually was used as a medication in the past to slow down an overactive thyroid, according to Richard and Karilee Shames in Thyroid Power.[vi]
The forms of fluoride being added to drinking water today to prevent tooth decay are not the pharmaceutical grade sodium fluoride that was originally researched for this purpose. Waste products derived mainly from the phosphate fertilizer and aluminum industries are the source of fluoride for 90% of fluoridated communities.[vii]
Worse yet, most of the fluoride put into the water supply does not end up on our teeth, but rather in lawns, swimming pools and rivers. We accumulate this fluoride from showering and swimming in it, and we take in an unknown amount from the fluoridated drinking water that may be used in juices, beers, wines and other drinks.[viii]
The five boroughs of New York City all have fluoridated water. To determine if your local water supply contains fluoride, contact the central water information center in your community.
You can protect your thyroid system from fluoride exposure by using a special dedicated fluoride filter or drinking bottled water. Most standard water filters do not remove fluoride efficiently, so you will need a separate fluoride filter to do the job.
In addition to using a fluoride filter, people with low thyroid conditions should install a chlorine filter on their showerhead. Chlorine gas is produced as the shower water sprays out, and this toxic substance will be breathed in as you bathe.
3. REDUCE OR ELIMINATE MEDICATIONS
If possible, reduce your use of medicine of all kinds to help detoxify the body. Medications that may weaken the thyroid include Premarin and Provera, two synthetic, chemicalized hormone products that are commonly prescribed as hormone replacement therapy for postmenopausal women. Birth control medications also may prove harmful to the thyroid.
- REDUCE YOUR ALLERGIC BURDEN
Any person with a low thyroid condition must seriously honor his or her immune system, since it may contribute to a suboptimal thyroid condition. One important way you can assist your immune system is to avoid foods and environmental allergens that cause reactions.
What is the connection? The immune system must process any allergens that enter the body, but it has only so much capacity to meet this ongoing demand. At some point the immune function reaches its threshold and begins to spill over like a rain barrel. This malfunction can set off an autoimmune process that causes the immune system to attack the tissues of its own body as if they were foreign invaders. The thyroid mechanism is one area commonly targeted by this improper, destructive response. Other types of tissue that may be targeted include the myelin nerve sheaths, skin, connective tissue and joints.
Each person’s level of immune-system overload will depend in part on the severity and frequency of allergic reactions. Dr. Feldman’s analysis of patient records in his practice has revealed a high correlation between allergic incidences and stress on the immune system. Some of the more serious autoimmune illnesses are lupus, rheumatoid arthritis, severe allergy states, multiple sclerosis, uveitis, scleroderma and Sjögren’s syndrome.
The goal is to lessen your body’s allergic burden so that all of the individual allergens cannot build to the point that they exceed the threshold level. Start by reducing or eliminating any foods to which you are intolerant. Pay particular attention to common food allergens such as wheat, dairy, sugar, beef, corn, eggs and yeast.
In addition, reduce your exposure to environmental allergens such as dust mites, molds, tree, grass and weed pollens, and animal dander, as well as seasonal allergens. Use air purifiers and dehumidifiers and take other steps to protect yourself from these allergic triggers.
- USE NATURAL THERAPIES
The lifestyle changes you make should be accompanied by natural therapies that help rebalance the thyroid functioning. A complementary health professional can guide you in the use of appropriate therapies. Dr. Feldman’s protocol for thyroid repair is individualized and may include many of the following components:
Thyroid-supporting nutrients. A number of minerals and amino acids help the thyroid system function optimally. They include:
- The follicles in thyroid tissues normally contain 40 times more iodide—the form of iodine found in foods—than does the blood. The thyroid’s concentration can be 300 times greater at maximal activity. Iodine is chemically combined with tyrosine, an amino acid. Be aware, however, that not everyone with a low thyroid condition needs to supplement iodine. An excess of this mineral may create problems, so each person’s level must be assessed by a knowledgeable health-care professional. For those who do need iodine, a certain subgroup will respond much better to iodine drops in the form of potassium iodide than to kelp or other iodine tablets.
- This mineral is needed in the process of converting T4 hormone to T3 in the liver, kidney and elsewhere. Even people who have healthy diets may not obtain sufficient selenium because some regions of the country have marginal levels of the nutrient.[ix] The food supply is low in selenium because it has been depleted from the soil.
- This nutrient plays a role in the regulation of energy production and the functioning of the mitochondria—both of which are closely associated with thyroid hormone. The RDA for magnesium is 350 mg, an amount that often is not met by the typical American diet.[x] In fact, as the diet includes more processed foods, adults are consuming an average of only 143 to 266 mg per day. Dr. Feldman often prescribes supplemental magnesium at higher doses, depending on a person’s mineral status.
- This mineral is an essential enzyme cofactor in metabolic pathways, and it affects the formation of thyroid hormones. In one study, zinc-deficient rats had 30% less concentrations of T3 and free T4.[xi] Meanwhile, many Americans have a marginal zinc deficiency. The optimal level of zinc supplementation for an individual may exceed 20 mg per day, depending on his or her status.
- This mineral promotes thyroid metabolism, according to anecdotal reports and case studies. The mechanism by which it does so is unknown.[xii]
- L-Tyrosine. This amino acid is a building block of the body’s proteins and the foundation of the thyroid hormones T4 and T3.[xiii]
- Like other free radical scavengers, glutathione offers protection in the body’s process of converting T4 to T3 in the liver and elsewhere.[xiv] N-acetylcysteine is a precursor of glutathione that is well tolerated and assists the optimization of this metabolite.
Herbs. Many herbal preparations are available that can aid the thyroid. They include skullcap (herb), parsley (plant) and uva ursi (leaf).
Homeopathic remedies. These natural formulas have a high rate of success in rebalancing the thyroid system, coupled with a low incidence of side effects. While their use in the United States has been limited to date, they are in wide use in England, France and Germany.
The only limitation with this modality is that you must work with a health-care practitioner who is experienced in the use of homeopathic sarcodes to rebalance thyroid functioning. The formulas are administered by oral pellets or drops and should be taken alone, sublingually, usually three times per day. In addition, the mouth should be kept empty for at least 15 minutes before and 15 minutes after taking the remedy. Homeopathic energy solutions are easily disturbed by food, nutrients or even water in the mouth, so they need a free energy field of their own to work effectively.
- CORRECT THE STRUCTURE OF THE NECK
Dr. Feldman’s patient records statistically verify that a poor alignment of the neck (including the upper back and base of the skull) is more prevalent in patients with thyroid problems. As a result, realignment modalities are occasionally needed as part of a complementary approach to rebalancing the thyroid system.
Two readily available modalities are osteopathy and chiropractic, both branches of structural medicine. The need for such treatments is not much of a leap philosophically, since the thyroid gland does sit anatomically inside the neck.
WHAT ARE THE RESULTS?
Using the above components, Dr. Feldman conducts a therapeutic trial for a few months to determine whether a patient’s thyroid can repair itself. The results often depend on the level of change made by the patient: The more a person is willing to do in terms of detoxifying the body, reducing allergic reactions and so forth, the better the odds that he or she will meet the goal of rebalancing both the central regulation of the thyroid system and the peripheral conversion of T4 to T3.
In general, Dr. Feldman’s records for participants in Gary Null’s Anti-Aging Support Groups and patients in his private practice show that about two-thirds of people presenting with a low thyroid condition do not need to take external oral thyroid medication. They are able to rebalance their thyroid system naturally.
The remaining one-third may improve their thyroid functioning as well, but not to the point that the system is working optimally. In such cases, the next step is to use a thyroid medication to replace the hormones the body is not producing optimally on its own.
When a therapeutic trial of thyroid hormone is indicated, physicians and their patients can choose from a number of medications that are available by prescription. These pharmaceuticals may be natural or synthetic in origin, but the fundamental difference lies in the types of thyroid hormones they contain.
The most commonly prescribed thyroid medication is Synthroid, which contains T4 only. Other thyroid medications contain both T4 and T3, thereby providing a direct dose of T3 hormone for those who do not convert T4 to T3 properly. The greater effectiveness of the T4/T3 combination was the subject of research published in the New England Journal of Medicine in 1999. The researchers found that the partial substitution of T3 for T4 may improve both mood and neuropsychological function in people with hypothyroidism.[xv]
Many complementary or alternative physicians prefer a natural prescription product called Armour Desiccated Thyroid Hormone because it contains both T3 and T4, reflecting the human thyroid’s production of both hormones. This medication is derived from the thyroid gland of a pig and closely resembles the human thyroid gland output. It is dried or desiccated and processed into tablets. People who take desiccated animal thyroid may also receive intermediary substances such as T1 and T2 thyroid hormones; some patients seem to need these substances, while others do not.[xvi]
Two other natural thyroid prescription options are Westhroid and Nature-Throid, both produced by Western Research Laboratories (see “Resources” for more information). These products contain all four hormones that occur naturally in the thyroid gland—T3 and T4, as well as T1 and T2. By supplying T3, Westhroid and Nature-Throid ensure that this hormone can be put directly to work, rather than assuming the T4-to-T3 conversion will occur at the tissue level.
The porcine source animals for Westhroid do not receive hormones or antibiotics, and their food is grown without herbicides, pesticides or artificial fertilizers.[xvii] Westhroid and Nature-Throid are identical in their hormonal content but use different binding ingredients. Nature-Throid is bound by microcrystalline cellulose, a derivative of paper that has a very low probability of causing allergic reactions. Therefore, it can be prescribed to people who have allergic reactions to Armour or Westhroid.
Another pharmaceutical option for patients is Thyrolar (Liotrix Tablets, UPS), a thyroid product that also contains both T4 and T3 hormones. Rather than being derived from animals, this medication is a synthetically prepared mixture of liothyronine sodium (T3) and levothyroxine sodium (T4). The T3-to-T4 ratio in Thyrolar dosages is 1:4. In a one-half grain dose, for example, Thyrolar contains 6.25 mcg of T3 and 25 mcg of T4.
Finally, many readers will be familiar with Synthroid, the leading brand of synthetic thyroid hormone. Most conventional physicians, including endocrinologists, prescribe this product, while complementary physicians typically do not use Synthroid because it contains T4 only. (Medications that provide a direct dose of T3 are not commonly prescribed. One such prescription product is Cytomel, a source of pure T3. See our “Resources” list for more information on Cytomel.)
Conventional physicians commonly argue that Synthroid provides a more accurate dose of the T4 hormone than is available from a natural product such as Armour. Interestingly, however, in 1997 the FDA reclassified all oral products made with T4 levothyroxine (including Synthroid) as new products because their stability and potency were problematic. The manufacturers’ new drug applications were required to be approved by mid-August 2001, according to The Medical Letter on Drugs and Therapeutics.[xviii]
The newsletter reports that Synthroid has experienced some problems with potency, even though it has “maintained a reputation as the ‘gold standard’ of thyroid replacement products.” In 1984, for example, some patients developed symptoms of thyrotoxicosis while on a constant dosage of Synthroid. In addition, the manufacturer recalled Synthroid lots in 1989, 1991, 1998 and 2000 due to subpotency.[xix]
For the minority of Dr. Feldman’s patients who require thyroid medication, he prefers the products that supply both T4 and T3: Armour, Westhroid, Nature-Throid or Thyrolar. He begins by prescribing a low dosage and gradually increases the medication until he discerns the optimal dosage for each person. Dr. Feldman also recommends that a medication containing T3 be taken as a twice-daily dose. This eliminates the objection that T3 has a shorter-acting time frame than T4.
Complementary physicians usually prefer to monitor a patient’s basal body temperature and the clinical symptoms as the main guideposts to the optimal dosage (see Part 1 of this article for more information on this temperature test). It may take several weeks before the benefits are realized and the basal body temperature returns to normal.
By contrast, most mainstream physicians guide the dosage level of Synthroid and similar drugs by the conventional blood levels of TSH and sometimes T4. As the body receives external T4, the pituitary feedback mechanism will sense the increased level of circulating T4 and reduce the output of thyroid stimulating hormone. It presumes the thyroid requires less direction to increase its production of the hormone.
The signs of too much medication (T3, T4 or both) may include the following: difficulty sleeping, feeling too hot, a racing heartbeat, sweating for no reason, twitching muscles or tremor, rapid thoughts and feeling too hyped up in general.[xx]
As noted earlier, people who require thyroid medication often must take it for a lifetime. Armour, Westhroid and Nature-Throid are very well tolerated, however, and Dr. Feldman has not seen any long-term negative effects of these products in his practice. The initial results with Thyrolar also are encouraging. Cytomel, the T3 medication, also can be effective when taken in two divided doses a day.
That said, it bears repeating that it is always better to rebalance the thyroid system so that it makes its own hormones and the liver, kidney and elsewhere then convert T4 to T3. That way, you will not be dependent on a medication to meet the body’s hormonal needs.
Another approach to thyroid therapy is that of Denis Wilson, M.D., whose treatment consists of a long-acting T3 pharmaceutical. Ordinarily, T3 is broken down rapidly compared to T4, but Dr. Wilson has developed his form of T3 to help rebalance some of the problems with the peripheral conversion of T4 to T3.
Dr. Wilson’s treatment is based on the fact that almost all of this conversion occurs in the tissues and cells of the body. Factors such as fasting and stress (caused by childbirth, divorce and so forth) cause the body to convert less T4 to T3 and more T4 to reverse T3, an inactive byproduct that inhibits the conversion process even more by using up the enzyme involved in this mechanism.[xxi]
Dr. Wilson’s regimen is an involved protocol that requires a lot of discipline on the part of the patient, and it may need to be administered in several cycles to be effective. So far, his therapy has received mixed reviews in the complementary and alternative medical community and is still being evaluated (See “Resources” for more information on the Wilson’s Syndrome Foundation).
HOLISTIC HORMONE BALANCE
As you work to improve your thyroid functioning, remember that this mechanism is intricately connected to the rest of the body’s hormonal systems (adrenals, pancreas, pituitary, ovaries, testes). All of the hormonal glands must work together efficiently, and a malfunction in any one of them may have a negative impact on the others.
Hormonal malfunctions that begin with a gland other than the thyroid can end up reducing thyroid functioning. For example, an imbalance of the ovarian functioning may interfere with the thyroid system over time. And if the adrenal glands are repeatedly stressed to the point that they wear out, they can have a negative effect on the thyroid as well.
As with the thyroid system, natural therapies also are available to support other hormonal systems:
OVARIES. If the ovaries are imbalanced (symptoms include irregular menstrual cycles, skipped cycles and infertility), a variety of nutrients may prove helpful. Among them are vitamin E, zinc, and herbs. Homeopathic sarcodes may help as well.
Some of the appropriate herbs for ovarian rebalancing are: damiana leaf (turnera diffusa var. aphrodisiaca), wild yam root (dioscorea villosa), partridge berry leaf (mitchella repens), black cohosh root (cimicifuga racemosa), cramp bark (viburnum opulus), dong quai root (angelica sinensis), evening primrose seed (oenothera biennis), flax seed (linum usitatissimum), burdock (arctium), chaste tree berry (vitex), and motherwort (leonurus).
ADRENALS. If the adrenal glands are suboptimal due to excess stress, caffeine or sugar consumption, the nutrients that can help rebalance and optimize this system include vitamin C, pantothenic acid, bioflavonoids and herbs such as licorice root (glycyrrhiza glabra). Homeopathic sarcodes also are available.
THE CONSEQUENCES OF MISSED DIAGNOSES
People suffer when thyroid disorders are not diagnosed because the conventional blood tests are “normal” and physicians do not recognize a patient’s symptoms as thyroid related. If a patient is profoundly depressed and is put on Prozac or another drug when the cause may be a low thyroid condition, his or her problems have just begun.
A missed diagnosis means the person will have two major problems to contend with: one is the underactive thyroid system itself and all of its ramifications; the other is the depression, which is often treated with antidepressants like Prozac in America today (for a discussion of the health risks associated with this drug, see “The Dangers of Prozac,” Parts 1 and 2, in the “Classroom on the Web” at www.garynull.com. From the home page, go to “Issues,” then “Classroom on the Web”).
As Dr. Stephen Langer aptly puts it, “When you have an undiscovered organic basis for a psychological problem, being put on psychotropic medication is like sitting on a thumbtack and being put on pain pills for the rest of your life. It has about the same effect. It wears the system down, and as a result the patient’s condition not only does not improve but will in fact deteriorate, because the underlying cause is not being treated.”
BOOKS & WEB SITES
The Food-Mood-Body Connection
By Gary Null, Ph.D.
Seven Stories Press, New York, NY, 2000
Thyroid Power: Ten Steps to Total Health
By Richard L. Shames, M.D. and Karilee Halo Shames, R.N., Ph.D.
HarperCollins Publishers Inc., New York, NY, 2001
Solved: The Riddle of Illness, Third Edition
By Stephen E. Langer, M.D. and James F. Scheer
Keats Publishing, Los Angeles, CA, 2000
Hypothyroidism: The Unsuspected Illness
By Broda O. Barnes, M.D., Ph.D, and Lawrence Galton
Dr. Joseph Mercola
1443 W. Schaumburg
Schaumburg, IL 60194-4065
For Women Only!
By Gary Null, Ph.D., and Barbara Seaman
Seven Stories Press, New York, NY, 1999
No More Allergies
By Gary Null, Ph.D.
Villard Books, a division of Random House Inc., New York, NY, 1992
THYROID HORMONE MANUFACTURERS
Forest Pharmaceuticals Inc.
Manufacturer of Armour Desiccated Thyroid Hormone
13600 Shoreline Drive
St Louis, MO 63045
Web site: www.forestpharm.com
Western Research Laboratories
Manufacturer of Westhroid and Nature-Throid
21602 North 21st Avenue
Phoenix, AZ 85027
Web site: westernresearchlaboratories.com
Jones Pharma Inc.
Manufacturer of Cytomel
1945 Craig Road
St. Louis, MO 63146
Web site: www.jmedpharma.com
Great Smokies Diagnostic Laboratory
Advanced thyroid hormone tests
63 Zillicoa Street
Asheville, NC 28801
Web site: www.gsdl.com
Quest Diagnostics Nichols Institute
Advanced thyroid hormone tests
33051 Calle Aviador
San Juan Capistrano, CA 92675
Web site: www.nicholsdiag.com
Advanced thyroid hormone tests via saliva levels
375 280th Street
Osceola, WI 54020
Web site: www.pharmasan.com
Comprehensive testing of antibodies that target the thyroid system
2211 Michigan Ave.
Santa Monica, CA 90404-3900
Tel.: 310-828-6543 or 800-421-7110
Web site: www.specialtylabs.com
American Autoimmune Related Diseases Association
22100 Gratiot Avenue
Detroit, MI 48201
Web site: www.aarda.org
Broda O. Barnes Research Foundation
P.O. Box 110098
Trumbull, CT 06611
Web site: www.brodabarnes.org
Environmental Research Foundation
P.O. Box 5036
Annapolis, MD 21403
Web site: www.rachel.org
Fluoride Action Network
82 Judson Street
Canton, NY 13617
Web site: www.fluoridealert.org
Thyroid Foundation of America
350 Ruth Sleeper Hall – RSL 350
Boston, MA 02114
Web site: www.tsh.org
Wilson’s Thyroid Syndrome
P.O. Box 1744
Lady Lake, FL 32158
Web site: www.wilsonsyndrome.com
[i] Shames, Richard L, M.D., and Shames, Karilee H, R.N., Ph.D. Thyroid Power: Ten Steps to Total Health. New York, NY: HarperCollins Publishers Inc., 2001, p. 166.
[ii] Shames, p. 183-184.
[iii] Colburn T, Dumanoski D, and Myers J. Our Stolen Future. New York: Dutton Publishing, 1996, p. 188.
[iv] Shames, p. 184-185.
[v] Null, Gary and Seaman, Barbara. For Women Only! New York, NY: Seven Stories Press, 1999, p. 535.
[vi] Shames, p. 169, 174.
[vii] Shames, p. 169.
[viii] Shames, p. 174.
[ix] Schrauzer GN, Sacher J, “Selenium in the maintenance and therapy of HIV-infected patients,” Chemico-Biological Interactions 1994; 91: 199-205.
[x] Morgan KJ et al, “Magnesium and calcium dietary intakes of the U.S. population,” J Am Cell Nutr 1985; 4: 195-206.
[xi] Kralike A et al, “Influence of zinc and selenium deficiency on parameters relating to thyroid hormone metabolism,” Hormone Metabolism Research 1996; 28: 223-226.
[xii] Yokoi K et al, “Effect of low rubidium diet on mineral status in rats.” Paper presented at the Second International Congress on Vitamins and Biofactors in Life Science. Feb 16-19, 1995. San Diego, CA.
[xiii] Chen TS et al, “Intestinal transport during the life span of the mouse,” J Gerantol 1990; 45: B129-B133.
[xiv] Brzezinska-Slebodzinska E, Pietras B, “The protective role of some antioxidants and scavengers on the free radicals-induced inhibition of liver iodothyronine 5’-monodeiodinase activity and thiol content,” J Physiol Pharmacol 1997; 48: 451-459.
[xv] Bunevicius R, Kazanavicius G, Zalinkevicius R and Prange AJ, “Effects of thyroxine as compared with thyroxine plus thiiodothyronine in patients with hypothyroidism,” New England Journal of Medicine Feb 11, 1999; Volume 340: 424-429.
[xvi] Shames, p. 99.
[xvii] Shames, p. 100.
[xviii] “What is going on with levothyroxine,” The Medical Letter on Drugs and Therapeutics July 9, 2001; Vol. 43 (Issue 1108):57.
[xx] Shames, p. 80.
[xxi] “Why is it?” and “Why is Wilson’s Thyroid Syndrome undiagnosable with thyroid blood tests?”, from www.wilsonsyndrome.com.