~Obesity, Part 5 - Thyroid and Other Hormonal Imbalances


  • Thyroid Blood Tests
  • Assessing Thyroid Function without Blood Tests

Overweight people often starve themselves all day long and then snack late into the night--a perfect formula for weight gain! As already noted, the American Journal of Clinical Nutrition reported an elegant study proving that food eaten early in the day generates more energy (diet-induced thermogenesis) than does food eaten later in the day (Weststrate 1993).

When some individuals first try eating in the morning, they often find that they are not hungry. Some physicians have suggested that these individuals force themselves to eat in the morning to re-regulate the eating schedule toward consuming a majority of calories early in the day. If you over consume high-glycemic foods, including sugar-laden desserts, do so for breakfast when the thermogenic (energy-burning) rate is the highest.

There are serious misconceptions about why people accumulate so much body fat as they age. One overlooked factor is that aging people have startlingly high levels of insulin in their blood. When the blood is saturated with insulin, the body will not release significant fat stores, even when a person restricts their calorie intake and exercises.

Other factors are also responsible for today's obesity epidemic. When an individual's hormones are out of balance, it may be impossible to achieve sustained weight management. Even when blood tests reveal "normal" thyroid hormone status, there is often an inability to convert T4 thyroid hormone into T3, which is necessary for natural thermogenesis (fat burning) to occur. T3 deficiency is another hormonal reason why excess weight accumulates with aging.

Additionally, if testosterone and/or estrogen levels are out of balance, excessive fat gain is often the result. (Very safe drugs and nutrients are available to correct these obesity-inducing hormone imbalances.)

As already stated, we tend to put on weight as we grow older, in part because aging impairs our ability to metabolize carbohydrates. Because most foods, besides fats, are eventually broken down into glucose (blood sugar), a decline in our ability to metabolize glucose is a significant cause of degenerative disease and the excessive weight gain associated with aging. One cause of impaired carbohydrate metabolism is subclinical thyroid deficiency.

Blood tests are not always reliable to diagnose subclinical thyroid deficiency. A study found that 14% of elderly people who were initially diagnosed as having normal thyroid levels were later found to have significant thyroid deficiency after undergoing extensive testing. Some physicians believe that most people over 40 have a subclinical thyroid deficiency that contributes to their weight gain (Bemben et al. 1994; Samuels 1998).

The thyroid gland secretes hormones involved in cellular energy expenditure. When an individual diets, the enzyme 5-monodiiodinase that is necessary to convert the thyroid hormone T4 into metabolically active T3 is reduced. T3 deficiency results in a slowing down of the body's metabolic rate and less food is metabolized to energy. This decrease in metabolic rate occurs because your body thinks you are starving and tries to conserve energy until more food is found.

Most of those who diet know about the "rebound effect"--the body resists losing weight while you "starve yourself," but then puts the weight back on with devastating speed when you begin to eat a little more. This is why dieting is such a miserable way to try to lose weight. But now you know why--it is because low T3 levels impair metabolic reactions by reducing your energy production and keeps you from losing weight. This biological mechanism involving thyroid hormone conversion, evolved over hundreds of thousands of years to counter starvation, is a sabotaging factor even when you deliberately eat less in an attempt to lose weight.

To illustrate how thyroid hormone status dictates body weight, consider the fact that when the thyroid produces too much thyroid hormone, the most common clinical symptom is significant weight loss. Hyperthyroidism is the name of the condition caused by an overactive thyroid gland. In 76-83% of cases, patients' first complaints to their physician are about how much weight they have lost.

On the other hand, clinical studies have shown that dieting produces a decline in the conversion of T4 to T3, resulting in a severe reduction in resting energy expenditure. This reduced metabolic rate prevents cells from burning calories to produce energy. If the cells do not take up glucose to produce energy, sugar is stored as fat within the body. The only way dieting can produce significant long-term weight loss is for the cells to take up glucose for conversion into energy rather than into body fat. When the flow of glucose is reversed from conversion into fat and storage in fat cells it is then necessary for the fat cells to release fatty acids for energy production. This is why thyroid hormone supplementation is so important to many people seeking weight loss through dieting. Not only does thyroid hormone replacement maintain healthy thermogenic activity, but it helps fight fatigue, depression, and other common disorders associated with calorie restriction. Individuals who have thyroid hormone deficiency should be prescribed a drug such as Cytomel or Armour (only under supervision of a physician).

While there are studies showing that thyroid supplementation promotes weight loss in some individuals, thyroid supplementation should only be used when there is evidence of a thyroid hormone imbalance due either to decreased secretion from the thyroid gland or decreased conversion of T4 to the more metabolically active T3 in the peripheral tissues. It is important to remember that as the body attempts to slow the metabolic rate to conserve body mass, many individuals become thyroid deficient in response to dieting. This is the normal response of the body to caloric restriction, a condition that prompts conservation of energy by inhibition of general metabolism.

Therefore, an individual with normal thyroid status before dieting may become thyroid deficient as a result of reduced intake of calories. For optimal fat-loss effects, an individual may require Cytomel or Armour drug therapy if they expect that eating fewer calories will result in significant long-term weight control.

In summary, thyroid hormones increase the metabolic rate of the entire body by accelerating the rate at which all energy sources are burned for energy and for heat. This is particularly important in Northern or colder climates. Thyroid hormones literally uncouple the metabolic processes that burn sugar and fat for the production of ATP, the energy currency of the body. ATP is a stored form of energy because it can later enter into reactions that transfer this energy to other bodily processes. Thyroid hormones uncouple the conservation of energy as ATP as fats and glucose are burned by allowing the released energy to be dissipated as heat rather than stored as ATP. Think of the role of thyroid hormones as conservers of energy. This function is useful to prevent eventual death due to starvation because it allows one to survive longer upon available stores of predominantly fat, while conserving glucose for those key organs that can only survive on glucose, such as the brain, kidney cortex, and red blood cells (at least initially for the brain). On the other side of the coin, release of thyroid hormones in cold environments prevents an early death due to freezing by accelerating the burning of predominantly fat (and some glucose) for energy production as heat.

The unifying principle here, and the fact most pertinent to the dieter trying to lose body fat, is that the body will almost always favor the burning of glucose over fat as long as there is a surplus of glucose. Fat is only burned when it is necessary to spare glucose. This is mainly due to the fact that glucose burns very cleanly and efficiently in all tissues, whereas, the utilization of fat requires the continual input of energy before fat can be burned. Another key fact is that fat can never be converted into glucose and the bodyís ability to store glucose as glycogen is very limited. Consequently, the body can store a hundred-fold higher amount of energy as fat than as glucose or glycogen. This is why fat is conserved for times when glucose supply is threatened. The dieter that can reduce carbohydrate intake long enough so as to drop blood glucose levels will trigger many hormonal reactions to increase the burning of both fat and excess protein. This is done predominantly through the release of adrenaline, which directly releases fatty acids into the blood from fat cells, and through release of adrenal glucocorticoids that accelerate the rate of conversion of fat and protein into glucose. In time, such as during prolonged starvation, the rate of protein catabolism is slowed and the body for the most part is running on fat metabolism for energy, while the catabolism of protein continues primarily to enable the synthesis of glucose for a small set of tissues that can not survive on fatty acids or other fatty acid intermediates.

Thyroid Blood Tests

There are several blood tests to assess thyroid function. If any of these tests indicate a thyroid deficiency, a physician should consider prescribing the appropriate dose of the drugs Cytomel (T3) or Armour desiccated thyroid to bring the level into the normal range.

If an individual's blood test shows an increase in thyroid stimulating hormone (TSH), this means that the pituitary gland is over secreting a hormone to stimulate thyroid function because of an apparent thyroid deficiency. The normal range for TSH can be as wide as 0.2-5.5 mU/mL. However, if TSH levels are above 2.0, this indicates that the individual may be hypothyroid and could benefit from Cytomel or Armour drug therapy. Remember, the higher the range of TSH, the more likely you are to be thyroid deficient. This relative thyroid deficiency predominantly prevents the excess calories consumed from being burned for energy.

A T4 (or total thyroxine) test measures the actual hormone being secreted by your thyroid gland. If T4 is deficient, most physicians will prescribe Synthroid, which is a synthetic T4 hormone. However, we recommend Cytomel (T3) or Armour desiccated thyroid instead of Synthroid (T4) because T3 is the more metabolically active form of thyroid that aids in thermogenesis (body fat burning). When evaluating T4 blood test results, the optimal range for males seeking to lose weight should be in a range of 8.5-10.5. Females under age 60 seeking to lose weight should be in the range of 9-11 mcg/dL. Women older than 60 years should be in the range of 8.5-10.7 mcg/dL. Too much T4 is a sign of hyperthyroidism that should receive immediate medical treatment (Tietz 1995).

Measuring the level of T3 (triiodothyronine) is one way to ascertain how much metabolically active thyroid hormone is available to the tissues. Normal T3 range is 2.3-4.2 pg/mL, but to lose weight, consider being in the range of 3.2-4.2 pg/mL. If levels are below this, Cytomel drug therapy is recommended. Most individuals begin at 12.5 mcg of Cytomel twice a day. The dose can be increased if blood T3 levels do not return to a normal range or if symptoms of thyroid deficiency persist. If T3 levels are above normal, this can indicate an overdose of drugs such as Synthroid or Cytomel or suggest hyperthyroidism.

A less frequently used blood test to assess thyroid function measures thyroglobulin (normal range, 1-20 ng/mL). If thyroglobulin is decreased, hypothyroidism is indicated. Another less commonly used blood test to assess thyroid function measures thyroid-binding globulin (normal range, 21-52 mcg/dL). If thyroid-binding globulin is increased, the individual is usually deficient in thyroid function (hypothyroid).

Assessing Thyroid Function without Blood Tests

Some physicians say it is more accurate to assess thyroid function by measuring body temperature in the morning before getting out of bed. This method, known as the Barnes Basal Temperature Chart, is believed to be especially useful in the treatment of obesity.

Every morning, as soon as awakening, before getting out of bed, put a thermometer under your tongue and let it remain there for three (3) minutes.

If your under-the-tongue temperature is less than 97.8-98.2 degrees Fahrenheit, you are likely hypothyroid. To get the most accurate results, repeat this test every day for at least 2 weeks. Write down the date, time, and temperature and bring this with you when you go to your weight-loss physician. Chronic morning basal temperature readings below 97.8-98.2 might indicate a need for thyroid hormone replacement.

In summary, as we age the thyroid gland releases less thyroid hormone. This facilitates conservation of energy so the same amount of calories consumed now result in energy storage as fat. This duplicates the textbook function of insulin in that insulin is regarded as the hormone of storage. Insulin stores energy in the form of fat and glycogen.


  • DHEA
  • Testosterone Deficiency and Abdominal Obesity in Men
  • A Scientific Approach for Inducing Fat Loss
  • How to Correct Hormone Imbalances Discovered by Blood Testing


We know that hormone imbalances (such as too much insulin, too little T3, etc.) are a cause of age-associated weight gain. The adrenal hormone dehydroepiandrosterone (DHEA) has kept old animals remarkably thin, but has not worked as well in humans. Nevertheless, many older individuals taking DHEA report anabolic muscle gain and fat loss. DHEA has been shown to boost insulin growth factor (IGF-1) in humans, and the increase in this youth factor may be responsible for the fat reduction and anabolic effects seen in some elderly people.

In individuals with low thyroid hormone output (hypothyroid), DHEA levels are low (Tagawa et al. 2000, 2001). For some, DHEA replacement could help protect against the decline in thyroid hormone output that occurs in response to reduced calorie intake.

For people over 35 year of age, the benefits of restoring DHEA levels to a youthful state include immune enhancement, protection against neurological disease, reductions in risks of cardiovascular disease, alleviation of depression, and protection against osteoporosis.

DHEA-replacement therapy is also suggested as part of an overall weight-management program for people over 35 years of age. The average daily dose of DHEA for men is 50 mg of DHEA, whereas women need only 15-50 mg. It is advisable to take DHEA early in the day.

Refer to the DHEA Replacement Therapy protocol before taking DHEA. DHEA is contraindicated in men and women with hormone-related cancers.

Testosterone Deficiency and Abdominal Obesity in Men

A consistent finding in the scientific literature is that obese men have low testosterone and very high estrogen levels. Central or visceral obesity (pot belly) is recognized as a risk factor for cardiovascular disease and type II diabetes. Boosting testosterone levels decreases the abdominal fat mass, reverses glucose intolerance, and reduces lipoprotein abnormalities in the serum. Further analysis has also disclosed a regulatory role for testosterone in counteracting visceral fat accumulation. Longitudinal epidemiological data demonstrate that relatively low testosterone levels are a risk factor for development of visceral obesity (Tenover 1992; Marin et al. 1998).

In one group of morbidly obese men, a study showed that serum estrone and estradiol were elevated twofold. Fat cells synthesize the aromatase enzyme, causing male hormones (testosterone and others) to convert to estrogens (Deslypere et al. 1985). Fat tissues, especially in the abdomen, have been shown to "aromatize" (convert) testosterone and its precursor hormones into potent estrogens (Schneider et al. 1979; Kley et al. 1980a,b; Killinger et al. 1987; Khaw et al. 1992; Marin et al. 1992, 1998).

Eating high-fat foods may reduce free testosterone levels according to one study that measured serum levels of sex steroid hormones after ingestion of different types of food. High-protein and high-carbohydrate meals had no effect on serum hormone levels, but a fat-containing meal reduced free testosterone levels for 4 hours (Killinger et. al. 1987).

Obese men experience testosterone deficiency caused by the production of excess aromatase enzyme in fat cells and also from the fat they consume in their diet (Khaw et al. 1992). The resulting hormone imbalance (too much estrogen and not enough free testosterone) in obese men partially explains why so many are impotent and experience a wide range of premature degenerative diseases (Blum et al. 1988).

Clinical findings have shed light on subtle hormone imbalances of borderline character in obese men that often fall within the normal laboratory reference range (Shippen et al. 2001). This means that if you are a man over age 40 and your physician tells you that your testosterone and estradiol are "normal," your levels are normal for a person of your age. It does not necessarily mean that your actual levels of testosterone/estrogen are in optimal, youthful ranges that would help to induce fat loss, especially in the abdomen. For complete information on boosting free testosterone and suppressing excess estrogen, refer to the Male Hormone Modulation Therapy protocol. Men contemplating testosterone replacement therapy should have a PSA blood test and digital rectal exam to rule out existing prostate cancer.

A Scientific Approach for Inducing Fat Loss

People seeking to lose weight should have their blood tested to determine obesity-related factors such as insulin, glucose, thyroid, testosterone, and estrogen.

The following chart reveals the most important blood tests that can help you and your physician facilitate optimal weight loss. It shows the hormone imbalances often seen in corpulent individuals compared to healthy ranges enjoyed by normal weight people.

How to Correct Hormone Imbalances Discovered by Blood Testing

Once blood testing results are received, a hormone-modulating program can be tailored to fit a person's individual profile. For instance, if there is any indication of thyroid deficiency, take the appropriate thyroid replacement medication (usually Cytomel). Starting dose of Cytomel is normally 12.5 mcg twice a day. Because reducing calorie intake may cause thyroid deficiency, have your blood tested every few months or use the morning basal temperature test to make sure that you do not need a thyroid replacement drug.

If DHEA levels are low (they almost always are in people over age 35), take the appropriate amount of DHEA (15-50 mg/day) to restore them to a youthful range. Stop eating after 6:30 p.m. and alter your diet by reducing consumption of high glycemic index foods.

 Range often seen in
overweight and obese individuals
Healthy range
(where you want to be)
Thyroid panel
- TSH2.0-5.5 mcIU/mL0.40-2.0 mcIU/mL
- Free T32.3-4.2 mcIU/mL(Upper half of range)
- T44.5-12.0 mcg/dL(Upper half of range)
- Fasting insulin20-60 mcIU/mL0-5 mcIU/mL
Men40-200 mcg/dL400-560 mcg/dL
Women30-150 mcg/dL350-430 mcg/dL
Free testosterone*
- Quest40-100 pg/mL150-210 pg/mL
- LabCorp.5-12 pg/mL18-26.5 pg/mL
Women0.0-0.9 pg/mL1.0-2.5 pg/mL
Men30-90 pg/mL10-30 pg/mL
Postmenopausal women50-150 pg/mLThe lowest amount needed to be symptom-free (Postmenopausal women who are not taking estrogen drugs are normally around 30 pg/mL.)
Postmenopausal women0.0-0.7 ng/mL>2.0 ng/mL
Pre-menopausal womenAmount can vary from 0.2-28.0 ng/mL during the cycle. Use time of cycle to ascertain deficiency.
Complete Blood Chemistry (CBC)To include blood counts, liver enzymes, and glucose.
PSAMen should have a PSA test to help rule out prostate cancer.

*Reference ranges for determining free testosterone vary depending upon the assay technique used for analysis. Quest Diagnostics employs the following reference values to determine free testosterone: adult males (20-60+ years), 50-210 pg/mL; optimal values for aging men without prostate cancer, 150-210 pg/mL; adult females (premenopausal), 1.0-8.5 pg/mL; adult females (postmenopausal), 0.6-6.7 pg/mL. When testing for free testosterone, be certain you know and understand the analytical method used.

In men, if free testosterone is below the optimal range, ask your physician to prescribe a transdermal cream providing 5 mg a day of natural testosterone. If estradiol levels are high (over 30), use 0.5 mg of the drug Arimidex twice a week to block the aromatase enzyme that converts testosterone to estrogen. Before using testosterone, men should verify that they do not have prostate cancer by having a blood test for PSA and undergoing a digital rectal exam.

Unlike in men, balancing estradiol levels in women is complicated and individualistic. Overweight women often have high estradiol levels because fat cells produce the aromatase enzyme that causes the body to make more estrogen. Liver function is very important in the metabolism of estrogens. If estrogen cannot be conjugated properly, it will not be excreted normally and levels will remain high. Cattle are implanted with estrogen pellets to "fatten" them up. A common complaint by women taking estrogen drugs is weight gain. Women should seek to modulate their estrogen levels, but should do so under the supervision of a physician with expertise in female hormone modulation.

Concerning estrogen, testosterone, and progesterone modulation in women, modulation has to be precisely carried out to induce weight loss without encountering unpleasant side effects such as hot flashes and depression. The general relation of progesterone to estradiol in healthy women is around 10:1 or higher. Below that a woman can become "estrogen dominant." In this situation, estrogen dominates the effects of the testosterone and progesterone. This is especially prevalent in overweight women because the fat cells induce excess estrogen, which creates a vicious cycle that should be broken to restore optimal hormone balance. Physicians often first try to raise testosterone and progesterone to offset the excess estrogen. If that does not help negate the effects of estrogen dominance, the next step is to try to lower estradiol. This must be done under a physician's supervision because it involves drugs (such as Arimidex) and must be done carefully to avoid unpleasant side effects. A woman with an estradiol value of 200 pg/mL would need 2000 pg/mL (2.0 ng/mL) of progesterone to offset it. Extra progesterone does no harm and most women like the feeling of having higher progesterone levels. Sometimes DHEA and testosterone supplementation can convert to estradiol, so that must be considered also.

Once you have achieved a youthful hormone profile, along with supplements that help facilitate weight loss, you are in a position to determine how much body fat you want to lose. There may be social occasions when you do not want to curb your appetite because you want to eat a big meal. You will find it easy to make healthy food choices such as including more fresh fruits and vegetables in your diet, avoiding high sugar snacks, and reducing total calorie intake.

Hormone modulation is the only practical approach for most aging individuals to rid their body of excess body fat and keep it off. If you are seriously concerned about protecting yourself against multiple degenerative diseases while improving your appearance, you should have your blood tested. Once the results are received, modulate your hormone profile accordingly by taking the drugs and supplements that can help restore youthful fat-muscle ratios. If you need a referral to a physician knowledgeable about hormone modulation, please call (800) 226-2370.

Continued . . .

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