The thyroid hormone is one of the main hormones that stimulate the furnace of the cells to produce energy. Without it, or when the thyroid hormone is low, food cannot be used and is stored as fat. The most common signs of hypothyroidism are:
- low temperature below 96.4 (depending who you read). But definitely feeling cold when everyone else is comfortable.
- fatigue for unknown reason(s)
- loss of hair and outer 1/3 of eyebrows
- dry, scaly skin especially of the shins
- constipation that is new for the person
- weight gain even though the person is eating normally for themselves. Especially if they are working out to lose weight
The symptoms and signs of low thyroid production can masquerade as depression, menopause, and psychosomatic. The interpretation of reading the laboratory results can mislead the physician thereby masking this diagnosis of the hypothyroid problem. The main blood test used to diagnose this is abbreviated to TSH (thyroid stimulating hormone). TSH is what is ordered by the physician to see if you have a thyroid problem. The numbers that the physician looks at to see if you are in the normal range has been controversial for a long time. Depending on the lab the TSH range was.35-5.5 but has now been changed to .3-4.5. This because it was found that too many cases were being missed by a lot of doctors looking at a high in the normal of 5.5. Doctors have been debating for years whether to lower the upper limit of what is considered normal for TSH since so many people whose blood work shows their TSH close to this upper normal limit still have the symptoms and signs of a low thyroid. Unfortunately, the missed diagnosis of hypothyroidism because of misleading lab results is not the whole story. The Colorado Thyroid Disease Prevalence Study found that when tested for thyroid dysfunction 10% of the study’s 25,862 subjects had abnormal findings (high normal being 3.5). That figure, if extended to the general population nationally, would mean there are about 13 million people with undiagnosed thyroid abnormalities. And if, as recommended by many physicians, the upper limit of TSH for thyroid dysfunction were reduced to 3, it would mean that 20% of the population is affected.
But when a busy physician takes a history of all the above symptoms and signs s/he may only hear depressed, tired and menopause and see lab results in the normal range. It would be in the patient’s best interest, I believe, to consider the signs and symptoms first and the blood work second.
A low thyroid level is called hypothyroid or hypothyroidism. Hypothyroidism may also be caused by a poorly functioning adrenal gland, since too much or too little cortisol affects the thyroid hormone. The adrenal gland produces cortisol and adrenaline in response to stress, and powers the Stress Response that prepares the body to fight or flee. In the initial stages stress causes higher than normal levels of cortisol: When the stress is chronic the adrenals eventually wear down, a condition known as “adrenal fatigue,” and cortisol production drops below normal levels. Therefore there is not enough cortisol available to sensitize cell receptors to accept the hormone nor to convert the T4 to T3.
As we have seen, production of many hormones, including thyroid, is lowered when the body is stressed. The Stress Response at first triggers the adrenal gland to produce higher levels of cortisol, that signals the body to put all its energy into the systems that will help to fight or run – the large muscles. To do this it takes energy away from functions that are not essential to those life-saving activities such as the sex hormones, thyroid and the GI tract. In the case of chronic stress, the adrenal is overworked continuously and the cortisol production becomes less and this too results in hypothyroidism.
The machinery of the body functions on precise amounts of each chemical, some measured in billionths of a gram, and this includes the hormones. This precise amount for each hormone is known as the physiological quantity (for that particular hormone). All the hormones have to be available in the appropriate physiological quantity in order to function in harmony for optimum well-being. It is like a symphony with each musician playing exactly the right notes in harmony with all the others.
Many women entering menopause not only experience the effects of diminishing sex hormones but also have a thyroid problem. I believe the depression that accompanies both menopause and hypothyroidism comes also from the physical changes: constipation, hair loss, feeling cold, gaining weight, fatigue that disrupt one’s life. I believe that the thyroid should always be explored before starting pre and post-menopausal woment on antidepressants. OK, now, I want to introduce what can go wrong with the thyroid and why conventional treatment may not work or even make the hypothyroidism worse.
The thyroid gland is stimulated by a complex feedback system. The pituitary gland stimulates the thyroid to produce T4 (thyroxin). The pituitary gland then responds to a feedback to the amount of T4 whether to stop stimulating the thyroid gland (enough of it) or to keep stimulating it (too little). In other words, the pituitary is responding to the amount of the primary(T4) hormone produced by the thyroid.. However, T4 is inactive, and must convert to active T3 in order to do its job. The conversion from inactive T4 to active T3 requires the right amount of selenium and cortisol. If selenium and/or cortisol are lacking or levels are inadequate, the feedback of T4 to the pituitary gland can make the level of TSH appear normal, since the T4 is sending the message that all is okay. The physician reading the lab report sees that the TSH is within normal limits, even though the patient is deficient in T3. All this is made more simple and explained with diagrams for the layperson in my book: Emotional Vampires and Your Hormones: an holistic physician’s view of how stress affects your well-being and what you can do about it.
And the plot thickens. Under stress, T4 may convert into what is known as reverse T3 (rT3). The rT3 molecule is just like the T3 molecule , except that one of the three iodine ions is in the wrong position. This tricks the receptor sites of the cells. rT3 binds to the receptors, thus blocking any remaining real T3. But since the rT3 does not have the same active stimulating effect as T3 because it is not of the right molecular arrangement, it will not stimulate the thyroid’s metabolic functions in the cells. Therefore, prescribing T4 will not solve the problem. The more synthetic T4 a patient takes the more rT3 is produced and the patient’s condition either does not improve or gets worse. When the stress levels rise the same enzyme (iodinase enzyme) which is responsible for the conversion of T4 to T3 is also used for conversion of T4 to rT3. Therefore, there is not enough of the enzyme to convert to both reactive T3 and rT3. For some reason the conversion to rT3 takes precedence. As of today, it has not yet been explained why rT3 takes precedence.
let’s say the patient is being treated with synthetic or natural T3 but still does not feel well. It is possible that the T3 is not getting into the cell, because to get into the cell the T3 is again dependent on selenium and a physiological level of cortisol and these may be deficient. Or if the T3 does get into the cell it may not work if zinc levels are low, because here it is dependent on zinc for its performance on the mitochondria in the cell. Mitochondria are the multitude of little factories in the cells that produce energy.
So to summarize: it is possible for a physician to be fooled by lab work. In this case, T4 levels remain normal but are not being converted to the usable T3 or as just explained the T3 cannot be utilized. The feedback of the T4 from the thyroid is still telling the pituitary that all is okay and therefore the TSH remains normal. But if the patient has all the symptoms and signs of hypothyroidism, then I would say the heck with the lab work being in the normal limits. An rT3 test is needed here and maybe some other thyroid tests: T3, FT3 (F=functioning), T4, FT4 and an autoimmune profile for thyroid (It is a possibility that the body has formed antibodies against an aspect of the thyroid hormone or the receptors for it).
Another interesting theory is that when cortisol is low causing the gut does not absorb normally. This can lead to leaky gut syndrome, which means that certain large protein particles that are foreign to the body are absorbed, and other nutrients that the body requires are not absorbed, such as amino acids.
Tyrosine plus iodine are needed to make the thyroid hormone. Therefore, if one has the leaky gut syndrome it may mean that tyrosine, an amino acid, is not being produced by other amino acids it depends on for its productions.
This was a shortened version of a chapter in my book (Thyroid and stress). I do hope though it illustrates how many things that the thyroid hormone depends on. Stress is still the big factor to sabotage a properly working thyroid and needs to be addressed whether the person is on synthetic hormones or more bio-identical thyroid hormones. Of course a good diet, exercise, a physician you can relate to and takes their time evaluating you and your smile and laughter goes a long way.