OVERVIEW: Although thyroid disease was first noted in the lat 1800's and associated with obesity, swelling, and heart failure, the true importance of the thyroid gland in health escapes the focus of many physicians still today. Although many individuals suffer with exhaustion, mental dullness, depression, constipation, dry skin, brittle nails, joint aches and cold hands and feet, few doctors consider thyroid as the disease that is the cause.
ANATOMY: The thyroid gland is positioned below the Adam's apple and is shaped like a bow-tie. This walnut sized gland secretes the thyroid hormones that regulates all the functions of all the cells in the body. Thyroid hormone is necessary for every cell to forge energy (in the Krebs's cycle). Without thyroid, there is a lack of efficient energy product and therefore lethargy. This is called thyroid deficiency syndrome, A small decline in the production of thyroid hormones can have dramatic effects on the cells of the brain, heart, liver, kidney, skin and bones. Hypothyroidism, left untreated, is called myxedema. The swelling that is seen in the face of severe hypothyroid individuals can also occur in the lungs and heart. One hundred years ago, myxedema was a major cause of death.
What was recognized by Broda Barnes, M.D. in the 19330's is that there are more than one thyroid. The commonly prescribed thyroid preparations, Synthroid™, Unithroid™, and Levothryoid™ are varieties of thyroxin (T4). However, tri-iodothyronine (T3) which is marketed as Cytomel™ is the more active form of thyroid. Although young people are able to convert stored T4 to active T3, this does not occur as commonly in elderly. At 60 years of age, at least one-third of women are hypothyroid. Most of us in clinical practice and research believe that more than two-thirds of everyone over 55 is hypothyroid. Replacement of T4 without T3 often fails to relieve all the symptoms listed above: cold hands, fatigue, depression, and dry skin and nails. Medical references to the benefits of T3 can be found at MEDLINE.
CLINICAL MEASUREMENT: Broda Barnes, M.D. recognized that one of the primary effects of thyroid is to raise body temperature. A fat, hypothyroid child will be one degree Fahrenheit cooler than a thin, active child. The measurements of thyroid function include TSH, T3 (free), T4 (free). But normal blood tests do not tell the complete picture of thyroid disease.
The control of the thyroid gland is TRH, thyroid releasing hormone, in the hypothalamus, deep within the brain. With age, the hypothalamus fails to release adequate stimulation: it acts like it is asleep. This is called 'down-regulation.' Under normal conditions, the TRH triggers the pituitary in the midbrain to release TSH, thyroid stimulating hormone. TSH causes the thyroid to produce T3 and T4 from precursors: iodine, tryptophan and T2 (di-iodothyronine).
Doctors have been taught to look for elevated levels of TSH. This implies that the pituitary cannot recognize adequate blood levels of either T3 or T4. A TSH over 100 means the individual is severely hypothyroid. A TSH less than 1 (when not on thyroid replacement) implies that the thyroid is overactive and out-of-control.
But, those of us researching thyroid disease have learned that these thyroid tests are just 'tests at best.' If the patient complains of a low body temperature on awakening (basal body temperature) then there is inadequate thyroid hormone no matter what the blood tests show. If there is fatigue, dry skin, brittle hair and weight gain on a low calorie diet, then there is insufficient thyroid hormone.
THYROIDITIS: Some hypothyroidism, clinically diagnosed as thyroid deficiency syndrome, may be caused by a condition called Hashimoto's thyroiditis. Hashimoto's thyroiditis is an autoimmune disease in which the body's own immune defenses destroy its own thyroid gland. Most cases occur in women; the reason is unknown. Other cases of Hashimoto's thyroiditis occur in other autoimmune diseases, including insulin-dependent diabetes mellitus, pernicious anemia and myasthenia gravis. It may also occur with greater frequency in people who are left-handed or who have prematurely gray hair.
Hypothyroidism can also be caused by drug treatments (e.g. alpha-interferon, used to treat hepatitis C) or destruction of thyroid tissue by radioactive iodine treatment or surgery for conditions such as Grave's disease or thyroid cancer It can also have a genetic origin, in which case it may manifest shortly after birth.
NATURAL THYROID REPLACEMENT:
A major controversy in the treatment of hypothyroidism concerns the use of natural glandular concentrates or extracts containing thyroid hormone (e.g., Armour Desiccated Thyroid Hormone™ and other brands derived from the thyroid gland of the pig or cow) vs. Synthetic (laboratory-made) thyroid hormone (e.g. Synthroid™, Levothroid™™, Unithyroid™ etc.). The synthetic product is promoted by pharmaceutical companies and most endocrinologists. Armour Thyroid™ and other natural thyroid preparations such as Thyrolar™ contain natural thyroid hormone. Although these preparations have been criticized by some for being "impure" or "inconsistent" from dose to dose, it should be noted that Armour Thyroid™ is most natural thyroid preparations. Armour Thyroid™ is F.D.A. approved and certified by the United States Pharmacopeia (U.S.P.). Armour Thyroid™ contains all four thyroid preparations (T4, T3, T2 and T1) and therefore, most closely resemble natural hormone thyroid hormone. At the proper dose, natural thyroid hormone works quite well and are preferred by nearly all "natural" or "alternative" physicians. Peer review journal articles have proven the benefit of 'natural thyroid' and T3 to improve general well being and decreasing depression.
We will continue patients on synthetic T4 if they insist and offer them the option of using a slow release compounded T3 product. The pharmacist mixes Cytomel™ (T3) into a medium to slow the absorption over 12 hours. Cytomel™ is not used because it is absorbed and destroyed in less than 2 hours.
According to a classic study conducted in 1974 by Dr. James Issacs, a pioneering cardiovascular surgeon from Baltimore, people who took ½ grain of thyroid along with vitamins and minerals over a period of ten years showed significant improvement in cardiovascular function. Some doctors recommend this for people over age 40 who have no overt endocrine disease. It has been pointed out that, even if one is not experiencing symptoms, all endocrine glands are beginning to slow down at this stage of life. The most common comment from people taking 1/4 grain of natural thyroid is "I just feel a little more energetic overall. My thinking seems a little clearer, and my bowel function is a little better."
Even if someone is already taking thyroid supplementation, most can still take a 1/4 - ½ grain of natural thyroid and tyrosine. "Unless you are in very brittle condition -- and brittle means to an endocrinologist that the amount you take has to be exactly right on -- you might consider adding 1/4 grain of the natural thyroid gland itself, as it also nourishes the rest of the endocrine network."