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Menopause Hormonal Summary

Growth Hormone (GH, also referred to as Human Growth Hormone (HGH) and Somatotropin). Decline in GH and Testosterone Production decreases lean body mass (muscle, bone, etc.) and increases body fat mass. Thyroid hormone induced thermogenesis is blunted with aging. Resistance to Leptin could result in a decreased ability to down-regulate appetite. GH production reaches its maximum around 20 years of age. GH concentration starts to decline in twenties and continues to decline 14% per decade throughout life. However Pituitary GH reserve remains intact during ongoing aging with no change in the amplitude of GH response to appropriate stimulation. Ghrelin which is produced in our stomach is a strong Growth Hormone secretagogue (increases the production of Growth Hormone). But in obesity the Ghrelin level is decreased and the stimulation of Growth Hormone secretion is decreased. So we produce less Growth Hormone when we have excess body fat. Growth Hormone by itself has a direct effect on tissues, organs, including muscle, brain, skin, bone and immune system. GH gets converted within the liver to active form called IGF-1 (Insulin like growth factor). GH increases anabolic activity which builds more muscle, denser bone and thicker skin. Increases fat burning and improves brain function and immune system. GH repairs muscle damage. About 80% of GH is secreted during slow wave (deep) sleep, particularly between 11:00PM – 1:00AM. The other 20% is secreted just after rigorous exercise. Patients with severe GH deficiency due to pituitary gland damage often suffer from sarcopenia (muscle loss), increased abdominal obesity, and the body composition changes usually observed with aging. GH replacement therapy in these patients significantly changes body composition by reducing fat mass and increasing lean body mass. Exercise increases GH secretion. When we lose excess body fat and increase lean body mass with Body-Profile Type nutrition and exercise, Ghrelin production increases in our stomach, and this increases the secretion of GH.

Melatonin. Melatonin is secreted from the Pineal gland (located in the brain). Its secretion is stimulated by darkness; it controls the daily (circadian) rhythms of sleeping and wakefulness with cortisol. Melatonin helps us sleep and is active at nighttime; Cortisol awakens us and is active in the daytime. Melatonin is a potent antioxidant and protects DNA from free-radical damage. When melatonin is not secreted enough we have trouble falling asleep. When we have less melatonin secretion and do not sleep well, this causes the body to produce less GH during sleep, which is essential for repair of your body’s cells, DNA, and tissues. Lack of sleep increases the production of cortisol, the stress hormone reviewed below. It is interesting to note that breast cancer patients respond better to chemotherapy and radiation therapy when they take melatonin.

Cortisol. Cortisol is an age accelerating hormone (stress hormone). In contrast to DHEA secretion by the adrenal gland, cortisol secretion does not decline with aging. Circulating cortisol levels do not change significantly but because the enzyme 11beta-HSD-1 activity is increased in fat cells which convert inactive cortisone into active cortisol in fat cells, increasing cortisol level the tissues. Inflammatory cytokines increases the effect of 11beta-HSD-1. As fat mass increases with obesity and aging, we have more production of inflammatory cytokines in fat cells, and this excess production increases the 11beta-HSD-1 activity and causes more cortisol production. Stress increases cortisol, elevated cortisol is related to breakdown of collagen and elastin in skin (causing wrinkles) and in joints, muscles, bones (causing pain). Cortisol has inhibiting effects on sex hormones, DHEA, Thyroid and HGH. High levels of cortisol damages in the thymic tissue and causes decreased T-Helper cells. (T-helper cells protect us from infections.) DHEA and Cortisol have opposite effects on T-helper cells balance. DHEA protects the thymus gland, because DHEA decreases the activity of 11-BHSD-1 enzyme and decreases the production of active cortisol. That’s why it is important to know your DHEA level during menopause and andropause years when you have excess body fat and not responding to the Body-Profile Type Fat Loss program. Also, clinical depression occurs as a result of a decrease in some brain chemicals that is related to elevated cortisol. In is important to know that blood level of cortisol does not show us the activity and the level of the cortisol in fat cells. So if you have a normal cortisol level in the blood, this does not reflect the activity in the fat cells that is happening with 11-BHSD-1 activity. In obesity 11-BHSD-1 level accurately reflects the active cortisol levels in the tissues.

DHEA (Dehydroepiandrosterone). DHEA is produced by the Adrenal Gland and its maximum concentration is achieved during the 3^rd decade of a person’s life. The level of DHEA from the 3^rd decade on, declines steadily and in oldest elderly the levels are only 10 to 20% of those seen in young adults. It is formed from cholesterol and is a precursor molecule to Testosterone both in men and women. Both DHEA and Cortisol is produced from Adrenal glands and their secretion is regulated by a hormone called ACTH (Adrenocorticotropic hormone) that is secreted from the anterior pituitary gland in response to corticotropin-releasing hormone from the Hypothalamus. ACTH induced secretion of DHEA is reduced in elderly subjects where as Cortisol secretion is increased. DHEA increases immune system response. In men, DHEA deficiency causes poor immunity, depression, low metabolic rate, low estrogen levels (because testosterone produces estrogen) and lower good cholesterol (HDL) levels. Excessively high DHEA levels in men causes high estrogen levels. In women DHEA deficiency can cause decreased libido, poor immunity, depression and low metabolic rate with weight gain. In excess causes acne, greasy skin, loss of scalp hair, facial hair growth and excess libido. In menopause you should get your DHEA level checked. If it is low discuss with your physician for DHEA replacement therapy.

Aldosterone. Aldosterone is produced in the adrenal gland, and excess aldosterone is associated with insulin resistance, weight gain, as well as hypertension. The aldosterone antagonist (inhibitor) called Spironolactone has been shown to improve insulin resistance and cause weight loss from body fat. In menopause, if you have water retention, hypertension, and especially if you have sleep apnea with excess body fat you should discuss with your physician about treatment with Spironolactone for hypertension and water retention to decrease the elevated aldosterone level.

Estrogen / Progesterone. Ovaries produce the principle female hormones. Parts of estrogens are produced in adrenal glands, especially after menopause. The three estrogens are, estradiol, estriol, and estrone. They are necessary for menstrual cycle, collagen synthesis, brain function and memory, bone mass and fat cell metabolism. In estrogen deficiency skin gets wrinkled due to collagen connection. Post menopausal women are prone to get short term memory impairment, bone loss, mood swing and hot flushes. An excess of estradiol and estrone has been linked to some overgrowth of ovarian, breast and uterine tissues and may cause cancer. Estriol has been called protective estrogen because it seems to inhibit the proliferative effects of the other two estrogens. Progesterone the other female sex hormone counterbalances the estrogens water retention effects and supports the building of new bone tissue. Progesterone has a calming effect on the brain and reduces the anxiety producing effects of estrogens. Excess progesterone may be converted to cortisol which causes rapid aging. Excess progesterone can cause PCOS (polycystic ovary syndrome) that causes insulin resistance, is characterized by obesity, excessive facial hair and lack of ovulation and menstruation.

Thyroid. Thyroid gland produces Thyroxine (T4) hormone and this gets converted into Triiodothyronine (T3) hormone, with the help of the trace mineral selenium. T4 gets converted to T3 (the more active form thyroid hormone) in the liver and other parts of the body. The pituitary gland produces Thyrotropin (Thyroid Stimulating Hormone, or TSH) to stimulate Thyroid gland to produce T4 and T3. As we get older starting during menopause and andropause some people will have a sluggish thyroid gland and less production of T4 and T3, which causes sluggish metabolism and excessive fat accumulation. In evaluation of menopause and andropause hormonal imbalance the thyroid hormones, T4 and T3 should always be included and tested for by your physician.