A damper controlling the flame of life — that’s your thyroid. Out of kilter, it can cause serious trouble
George H. Waltz, Jr.September11946
HOW'S YOUR THYROID?
A damper controlling the flame of life — that’s your thyroid. Out of kilter, it can cause serious trouble
George H. Waltz, Jr.
PUT YOUR fingers on each side of your throat, just above your collarbone. The chances are that you won’t feel anything—but beneath the skin, nestling round your windpipe like a saddlebag, is one of the most important glands in your body. It weighs less than an ounce, yet it is your system’s master control.
Have you ever wondered why two people of about the same age, living the same kind of life, eating the same foods, getting about the same amount of recreation and exercise, and being confronted with the same worries, are sometimes diametric opposites physically and emotionally? One will be thin, nervous and excitable, restless, highly colored, and have a high pulse rate. The other will be very much overweight, slow, perhaps even mentally dull, sallow-skinned, have a low pulse rate.
These two people are typical pictures of the two opposites in upsets in that little gland, called the thyroid, that rests in your neck. One, the thin one, shows the symptoms of a thyroid that is overactive. The other, the symptoms of an underactive thyroid.
This does not mean necessarily that all your thin friends are suffering from overactive thyroids, and all your stout ones from thyroids that are underactive, but the combination of underweight and nervousness and uncontrollable overweight and lethargy are thyroid disorder symptoms.
The main function of the thyroid gland is to produce a secretion known as “thyroxine,” which the thyroid-called a ductless gland because it has no ducts or outlets feeds directly into the blood stream. The important thing is that on its tour through the body the thyroxine controls the production of heat and energy.
Basically, our bodies operate much like a
furnace. We consume food. We breathe oxygen. The food (fuel) is burned, and from it we get the energy to think, walk and work. The secretion from our thyroid acts as the damper in our human furnace, controlling t he combustion of our fuel and the production of our energy. When the amount of thyroid secretion is just right we consume our fuel at just the right rate, and obtain our energy at just the proper flow.
If the damper is closed a little too much too little secretion from our thyroid—our fuel piles up and the body fire burns low; our heart slows up because less oxygen, which is carried by the blood, is needed by the body’s cells and tissues. On the other hand, if the damper is too wide open—too much thyroid secretion—our fuel is used too fast; more oxygen is required by the cells and tissues, so our heart speeds up to pump more blood, we get thin, and irritable and excitable.
Scientific curiosity about the thyroid goes back several thousand years. Early Greek writings show that the elders of that day realized the existence of the thyroid, though they had no idea of its important function.
Various early writers noted it as “a device to keep the throat warm,” as “a padding of tissue to beautify the lines of the neck,” as “a purely prenatal organ,” and many of them rightfully pointed out the fact that a swelling of the thyroid, known as goitre from the Greek word meaning “shield-shaped,” was more prevalent among inland peoples than among those who lived on the seacoasts. It was not until
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How's Your Thyroid?
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about 100 years ago, however, that any positive steps were made to determine just what the thyroid was and what it did.
It long had been known that there was a definite relationship between the thyroid gland and iodine. Over 4,000 years ago the Chinese used burned sponge, high in iodine content, in the treatment of goitre. The ancient Greeks followed much the same treatment. It was not until 1895, however, when two researchers, Baumann and Oswald, determined by actual chemical analysis the fact that iodine—the main ingredient in the brownish antiseptic tincture we put on cuts—was an important constituent of healthy thyroid tissue.
Then in 1916 another researcher, by the name of Kendall, following the leads of Baumann and Oswald, succeeded in producing an actual compound, which was six tenths iodine and had much the same effect on the human body as the actual secretion of the thyroid. It was he who was responsible for coining the name, “thyroxine,” which is a combination of some of the letters taken from the tongue-twisting chemical name of the compound.
These experiments all added up to give a full explanation of why people who lived away from the sea, and whose diet was lacking in the iodine foods, such as fish and vegetables grown in iodine rich soil, were susceptible to colloid goitre. Being deprived of the raw material it needs, the thyroid works overtime in a vain effort to provide the thyroxine requirements of the body on a reduced supply of iodine. The result: a swelling of the gland, known as colloid goitre.
Generally, goitre evidences itself fairly early in life, and if caught immediately, the treatment is simple and effective—an addition of iodine to the diet. Prevention, however, is far better than cure, and in many localities where colloid goitre was at one time prevalent, manufacturers are bound legally to add iodine to salt sold for kitchen or table use.
In test communities where iodine was added to the salt sold in the dis-
trict, the prevalence of goitre was greatly reduced. A survey conducted in the public schools of Detroit, Mich., in 1924 showed the alarmingly high goitre rate of 36 out of every 100 children. After two years of selling only iodine-fortified salt, the rate fell to two out of every 100.
Another graphic illustration of how an all-out health department campaign urging the use of iodized table salt can control goitre is shown by a survey made in Michigan’s Houghton County, just across Lake Superior from Port Arthur, Ont. Less than two per cent of the people who used iodized salt regularly had goitre, while almost 15% of those who never used it suffered from goitre. In 10 years of preventive education the incidence of goitre in the county was cut from 32.7% to 5.2%.
In recent experiments scientists have measured the time it takes the iodine in the foods we eat to reach the thyroid, and the time required for the thyroid to synthesize the thyroxine. By using radioactive iodine, University of California doctors have been able to trace the course of iodine in the body.
Portions of radioactive iodine were fed to laboratory animals, while the scientists, using an instrument, called a Geiger counter, which is sensitive to radiations, followed the iodine’s progress. In less than two minutes the “tagged” iodine had reached the thyroid, and within two hours it had been converted into thyroxine.
Iodine-lack can be passed along by a pregnant mother to her unborn child in the form of a defective thyroid. The result is a disease called cretinism, in which normal growth—mental as well as physical—is stunted. Unfortunately in these cases the thyroid gland is either almost lacking or so ineffective that even powdered thyroid, fed to the child under expert medical guidance, brings about only an occasional cure.
In thyroid deficiency—doctors call it hypothyroidism—that develops in childhood or in later life because of an injury to the thyroid or disease or to a general wasting away of the gland due to age, thyroid medication often brings about miraculous physical and mental changes. By feeding the patient just the right amount of
powdered thyroid, obtained from cattle, the doctor is able to bolster the underactive gland, and strike just the right balance.
Once the proper flow of thyroxine is maintained, the patient regains normal growth—he loses weight, his entire system speeds up, and he begins to burn his fuel at just the right rate. Children who at 12 or 14 have been overly fat, mentally and physically slow, and generally subnormal, have become completely normal after a few years of thyroid medication
Until recently the principal treatment for an overactive thyroid (hyperthyroidism) in extreme cases consisted of an operation in which a portion of the thyroid was removed to reduce its thyroxine-producing capacity. It was up to the surgeon to decide just how much should be removed to bring about the desired reduction—a delicate decision. Recent clinical tests, however, show promise of a successful treatment that does not require the surgeon’s knife.
Early in 1942 a New Zealander, Dr. T. H. Kennedy, noted that a chemical obtained from rapeseed oil, which he labelled thiouracil, was capable of depressing the thyroid in laboratory rats, and thus slowing down the body combustion rate. A year later another doctor, Dr. E. B. Astwood of the Harvard Medical School, reported the successful use of thiouracil on humans, subsequent to which similar tests were made by Dr. J. K. McGregor, Hamilton, Ont. Further study showed that the drug slows down the body processes by reducing the thyroxine production of the thyroid gland.
So far, more than 10,000 human patients have received the thiouracil treatment, successfully in 90% of the cases—thin, excitable hyperthyroids have gained their normal weight and normal emotional and physical stability. Yet it is too soon to hail thiouracil as a complete cure for overactive thyroid.
Some reports have shown as high as 20% of patients treated suffering toxic reactions to the drugs—often only a rash, more rarely a disease called agranulocytosis, in which the white blood cells decrease rapidly in the blood stream. In a reported one of every 250 people given repeated doses of thiouracil this blood disease may be fatal, yet even this hazard compares favorably with the fatality rate when surgical treatment is given.
For this reason some doctors use thiouracil not as a substitute for surgery but merely as a preliminary treatment before operating. Yet many others are convinced that administration of the drug is effective in itself, and that careful treatment can safeguard the patient from toxic reactions. Even the administration of powdered thyroid to boost an underactive gland is a delicate matter of balance, for this “damper” regulating the human combustion system may swing too far open or shut very easily, once it has been put out of balance. Then, too, the condition of the thyroid gland changes even with the seasons, so it must be watched, and adjustments made in the medication accordingly.
Fortunately, your doctor has a good guide to help him to diagnose thyroid trouble and to prescribe treatment. Since the thyroid gland controls the energy - producing processes of the body, an indication of the general condition of the thyroid can be obtained by examining the “internal combustion” rate of the individual. If this is too high, the signs point to an overactive thyroid; if too low, an underactive thyroid is indicated.
A doctor gauges the body’s combustion rate by measuring the oxygen consumed and the products of combustion which are exhaled when the body is at rest and there is no food in the stomach. Called the “basal metabolism test,” these measurements give an accurate indication of the basic, or minimum, amount of energy required to keep the body warm and the various organs alive and functioning.
Each of us has a normal basal metabolism rate which can be calculated mathematically according to our age, sex and weight. The basal metabolism test shows, in percentage, just how far we are above or below that theoretical norm.
Average rates for healthy people range from plus 10 to minus 10. Within these percentages there is no indicated trouble. A greater plus or minus, however, indicates a possible thyroid upset. If, for instance, the test shows a minus 29, it indicates that the patient’s combustion is slow, and the thyroid needs speeding up. Similarly, if the test shows a plus 20, it indicates that combustion is too rapid, and the thyroid needs slowing down.
By giving the test at regular intervals during treatment, the doctor can tell just how the medication is affecting the thyroid, and either increase it or decrease it to maintain just the right balance for normal metabolism.
An even more striking treatment for advanced cases of an overactive thyroid (exophthalmic goitre) is now in the experimental stage, in which doses of radioactive iodine are fed to a patient. While the normal effect of a patient’s absorbing added iodine is to increase the gland’s production of the thyroxine, radioactive iodine has just the opposite effect—carried quickly to the gland the radioactive particles destroy some of the cells in the thyroid, thus reducing its ability to produce thyroxine.
A pinch of “radioiodine” in solution was successful in restoring overactive glands to normal in 35 of 46 cases given the treatment, according to a report by Dr. Earle M. Chapman of the Massachusetts General Hospital, before the recent convention of the American Medical Association. Three other patients required two doses each, in five cases three drinks were required—and in only three of the 46 patients did mild symptoms remain after the treatment had been given.
Help From the Atom
The new radioiodine treatment might be visualized as a form of “internal surgery”—instead of the surgeon’s knife cutting away a piece of the thyroid gland, the radioactive particles “cut” it away cell by cell, much as radium attacks a cancerous growth. Some doctors believe it may prove possible to attack cancer of the thyroid in exactly the same manner, perhaps by increasing the dosage of radioactive iodine beyond the strength required merely to reduce the size of a noncancerous gland.
But this is so new a development that, apart from the report read to the convention, no information about it has as yet appeared in official medical literature. While it is possible that this treatment may eventually be accepted, it is still in the experimental stage and much remains to be proved by clinical tests. Radioactive iodine is not yet ready for distribution to the public; it is not available at all in Canada, nor is it likely to be for some time.
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