Ray Peat on estrogen

January 3, 2026

Estrogen's influence on tryptophan metabolism

"Estrogen strongly influences tryptophan metabolism by increasing its conversion to serotonin – at the expense of niacinamide, which explains the symptoms of pellagra when the diet is low in tryptophan. When sufficient protein is present in the diet, the promotion of serotonin synthesis does not lead to a niacinamide deficiency; however, conditions that increase the influence of estrogen also exacerbate serotonin-related dysfunctions."

September 2019 – Ray Peat's Newsletter

Estrogen, serotonin and the water retention cycle

"Estrogen increases the production of serotonin, and both substances increase the production of prolactin, activate the renin-angiotensin system, and increase the release of the antidiuretic hormone vasopressin – all of which work together with estrogen and promote water retention. Serotonin, in turn, increases the production of estrogen, so a vicious cycle can easily develop under stress."

September 2019 – Ray Peat's Newsletter

Serotonin, estrogen, and the stimulation of pituitary hormones

"Serotonin, along with estrogen, is the most important promoter of prolactin secretion and also promotes TSH, ACTH, FSH, LH, GH, MSH, POMC, vasopressin and oxytocin – that is, all pituitary hormones."

September 2019 – Ray Peat's Newsletter

Estrogen's influence on water retention and salt cravings

"Under the influence of excess estrogen, the body stores extra water, and normally the appetite center should compensate for this water by triggering a craving for additional salt. However, if you avoid salty foods during such phases (or take a diuretic), the blood cannot carry as much water as it would with sufficient salt intake, so the salt remains in the tissues instead of being transported to the kidneys."

Nutrition For Women

Estrogen production in men under stress and hunger

"Men produce estrogen, especially under stress such as hunger, alcoholism, or liver damage. In a famine, men may even begin to breastfeed."

Nutrition For Women

Stability and lack of adaptability of testosterone in men

"The primary male hormone testosterone possesses chemical and functional properties of both estrogen and progesterone; this combined effect gives men short-term stability (less goiter, migraine, etc.) but less long-term adaptability (higher mortality in infancy and old age)."

Nutrition For Women

Estrogen's role in cell renewal and threat response

"Estrogen is the hormone of beginnings, a kind of biochemical eraser that can delete recently stored information and restore the underlying original capacity for growth. When we are threatened by injury or aging, we need the ability to renew cells."

Nutrition For Women

Estrogen's influence on the production of prolactin and growth hormone

"Estrogen promotes the production of prolactin, a protein hormone, as well as its close relative, growth hormone. Ionizing radiation, aging, and oxygen deficiency cause biochemical changes similar to those caused by estrogen."

Nutrition For Women

Substances that counteract estrogen in cancer therapy

"Anything that causes tissue atrophy tends to promote cancer. The crucial question, therefore, is: What can induce differentiation and functional activity in cancer cells? There are many substances that promote differentiation and counteract the effects of estrogen, and some of these have proven useful in cancer therapy. Estrogen-inhibiting substances include dopamine and nickel, prolactin inhibitors; chalones, the tissue-specific proteins that inhibit cell division (and possibly also – temporarily – memory peptides); the aprotic solvents DMF and possibly DMSO; progesterone and testosterone; thyroxine and iodine; magnesium-ATP, the stable form of the biological energy molecule; vitamin A, a protein-sparing nutrient that promotes differentiation; and vitamin E (and the closely related coenzyme Q, or ubiquinone)."

Nutrition For Women

Estrogen's influence on experience and memory formation

"Argumentation patterns are stabilized as knowledge and as developmental changes in tissue—growth, aging, and their consequences. An excess of estrogen or other factors that inhibit proteolysis could block the ability to experience. The difficulty in remembering dreams is probably related to this synthetic (non-proteolytic) dominance of the parasympathetic nervous system during sleep."

Nutrition For Women

Estrogen increase due to stress and its effects on male behavior

“Stress leads to an increase in estrogen and a loss of anti-estrogens such as thyroid hormones, progesterone, and (in males) testosterone. Male monkeys that are bullied exhibit reduced testosterone levels, and this effect persists long after their environment has improved. The stress of submission appears to lead to an adaptation toward passivity. This passivity prevents further injury, but how stressful this continued submission is remains unclear.”

Nutrition For Women

Selye's discovery of adaptation phases and stress immunization

"Hans Selye discovered that the adrenal glands are an essential part of our adaptation system. In the first phase of stress, a shock response occurs (with changes similar to those of estrogen dominance), damaging various tissues. In the second phase, the adrenal glands protect the organism, and this protection lasts until exhaustion sets in. By exposing rats to prior stress, Selye found that he could induce adaptation to subsequent stressors—a kind of stress immunization."

Nutrition For Women

Energy inefficiency in the estrogen-dominated state compared to the oxidative state

"From an energetic point of view, the estrogen-dominated metabolic state is less efficient than the oxidative state, which is dominated by thyroid hormones and progesterone (or testosterone). The estrogen state resembles the learned helplessness state in rats and is parasympathetically oriented, in that many chemical equilibria shift away from the mobilized sympathetic or adrenergic state. For example, the estrogen state lowers blood sugar, while the mobilized state conserves glucose by oxidizing fat."

Nutrition For Women

Societal influence on hormonal states and physiological changes

"The hormonal conditions for easy submission are modifiable—both within the individual and from generation to generation—and better social conditions can improve our physiology. High estrogen traits can be acquired and passed on to offspring, as LC Strong discovered in his mice and as was recently confirmed in rats subjected to stress during pregnancy."

Nutrition For Women

Contradiction between medical practice and controlled scientific studies

"Controlled scientific studies play hardly any role in medical practice. The widespread use of estrogen is not only not supported by such valid studies, but even contradicts most of the available data."

Nutrition For Women

Slower liver function in women and difficulties breaking down estrogen

"It is known that women's livers remove chemicals from the body more slowly than men's. If the liver does not remove estrogen from the body quickly enough, it accumulates – this is why male alcoholics often develop breasts. Estrogen preparations and tranquilizers further increase the burden on the liver. A poor diet makes it impossible for the liver to function properly."

Nutrition For Women

Protein is crucial for the breakdown of estrogen.

"Lipschütz (Steroids and Tumors, 1950) reported that protein is crucial for the breakdown of estrogen."

Nutrition For Women

Progesterone's antagonistic effect on estrogen and tumor regression

"Progesterone is a direct antagonist of estrogen; Lipschütz (and Korenchevsky) have shown that progesterone can reverse estrogen-induced tumor growth."

Nutrition For Women

Thyroid hormone and vitamin A counteract the effects of estrogen

"Thyroid hormones and vitamin A promote protein metabolism and counteract some of the effects of estrogen. In fact, it is known that an overactive thyroid can cause estrogen levels to drop below normal."

Nutrition For Women

Estrogen-related blood clotting and metabolic disorders

"It is well known that taking estrogen can cause the blood to clot too easily. Other effects include anemia, low blood sugar, and slowed liver function."

Nutrition For Women

Role of the liver in estrogen metabolism and its effects on libido

"Normally, the liver treats estrogen like a poison and removes it from the body immediately. If the liver becomes sluggish due to malnutrition or too much estrogen (or other damage), the hormone can accumulate to very high levels. Since estrogen is metabolically antagonistic to progesterone and testosterone, I think the pill can decrease libido by counteracting these other hormones."

Nutrition For Women

Synergistic effect of copper with estrogen

"Copper appears to act synergistically with estrogen and could have a similar effect."

Nutrition For Women

Vitamin E as an anti-estrogenic vitamin

“Vitamin E biochemically does several things that are the exact opposite of what estrogen does, which is why it has been called the anti-estrogenic vitamin.”

Nutrition For Women

Increased vitamin E requirement due to estrogen during pregnancy

"Estrogen appears to increase the body's need for vitamin E, as well as for many other nutrients. A pregnancy, which can leave the woman with elevated estrogen levels, seems to increase the amount of vitamin E needed to maintain a subsequent pregnancy – if one can extrapolate from animal studies to humans."

Nutrition For Women

Estrogen's influence on oxygen metabolism and the nervous system

"I suspect that estrogen works primarily through its effect on oxygen metabolism – a kind of biochemical breath-holding. For certain nervous systems, both taking vitamin E and experiencing an orgasm could be compared to taking a deep breath."

Nutrition For Women

Endocrine interactions and the compensatory role of the thyroid gland in relation to estrogen

"The concept of physiological compensation is sometimes overlooked in the interpretation of endocrine interactions, leading to confusion. The brain-pituitary system (not just the hypothalamus, as the entire brain and sensory system are involved as reflex regulators) is arguably the most important regulatory or compensatory system. When an animal is injected with estrogen, the level of thyroid-stimulating hormone increases (Brown-Grant, J. Endocr. 35, 263, 1966). This should be understood as an indication that the peripheral effects of estrogen can be compensated by thyroxine. If thyroid function is borderline, this also suggests that elevated estrogen levels are not adequately compensated peripherally. There are many well-known examples of the metabolic or functional contrast between estrogen and thyroid hormones."

Nutrition For Women

Thyroxine's inhibitory effect on estrogen-induced thymic atrophy

"Apparently, thymolysis is inhibited by thyroxine and promoted by estrogen (stress, radiation and hunger also cause shrinkage of the thymus)."

Nutrition For Women

Attention to iodine and electrolytes in estrogen imbalance

"Iodine, protein and electrolyte balance should be given special attention in women who may have an estrogen imbalance."

Nutrition For Women

Relationship between estrogen dominance and infertility in mice through oxygen availability

"Infertility in mice is also associated with an increased estrogen-to-progesterone ratio. My research showed that the likely mechanism by which excess estrogen causes infertility lies in the restriction of oxygen availability."

Nutrition For Women

Estrogen, reproductive aging, and cancer theories

"This anti-oxygen-related effect of estrogen suggests that research on reproductive aging is converging with Warburg's theory that impaired respiration is the primary defect in cancer, as well as with Selye's observation that the effect of estrogen is similar to the first shock phase of the stress response."

Nutrition For Women

Estrogen causes hypoxia in various biological systems.

"Estrogen causes hypoxia in virtually every conceivable location – from the lungs to vascular fibrin and extracellular collagen, as well as edema and intracellular metabolism."

Nutrition For Women

The opposing mechanisms of action of estrogen and progesterone and their biochemical interactions

"This polar opposition between estrogen and progesterone also includes the antagonistic opposition of cyclic AMP and cyclic GMP, as well as, to some extent, a corresponding opposition of different prostaglandins (it has been suggested that this involves different populations of lysosomes, but I suspect it is related to the superoxide dismutase enzyme system and its inhibition or activation, as one of my tests for determining estrogenic action turns out to be an inverse indicator of SOD activity)."

Nutrition For Women

The role of progesterone in various diseases

"Even though progesterone seems to cure almost everything, it should only be used when the biochemical mechanism is reasonably clear. A progesterone deficiency can be misdiagnosed as epilepsy, Bright's disease, multiple sclerosis, or even estrogen deficiency (as in menopause). It can influence susceptibility to many diseases, including herpes infections, vertigo, perceptual disturbances, varicose veins, mastitis, fibroids, and endometriosis. In my experience, cyclical edema, depression, and migraines are always stopped by progesterone."

Nutrition For Women

The complex role of the estrogen/progesterone ratio in health

"An excessive ratio of estrogen to progesterone is generally more effective than either a simple excess of estrogen or a deficiency of progesterone alone, but even this ratio is influenced by other factors, including age, diet, other steroids, the thyroid gland, and other hormones."

Nutrition For Women

Stress, seasons and hormone levels in humans

"Excessive stress (due to increased estrogen and/or depletion of progesterone, etc.) can trigger symptoms in someone who previously had none. A summer in Alaska, with its unusually long days, can alleviate the symptoms of a chronically affected individual. Dark, cloudy winters in England or the Pacific Northwest act as strong stressors, leading to lower progesterone in women and lower testosterone in men."

Nutrition For Women

Dietary protein deficiency as a cause of estrogen excess

"A very common cause of excess estrogen is a lack of protein in the diet – the liver simply cannot detoxify estrogen if it is malnourished."

Nutrition For Women

Nutritional and hormone-related influences on cellular respiration

"Various nutritional, hormonal, or toxic conditions affect respiration in different ways: For example, vitamin E deficiency, estrogen excess, toxic hyperthyroidism, and DNP (the formerly popular, carcinogenic reducing agent) lead to oxygen consumption without producing the normal amount of usable energy. A deficiency in vitamin B2 or copper can prevent oxygen utilization. Cancer (contrary to a persistent belief) involves a respiratory defect and leads to a tendency toward hypoglycemia, which is often compensated for by the conversion of protein to sugar, ultimately leading to the wasting state of cachexia."

Nutrition For Women

Dietary relief of tension through copper or estrogen

"Tensions caused by excess copper or estrogen can be alleviated through diet. Zinc supplementation is usually necessary – about 20 mg per day; approximately 30 mg of vitamin B6 has been recommended for this problem, although the amount can vary from person to person. The other B vitamins, as well as vitamins E and A, should also be included."

Nutrition For Women

Stress-related effects on the thyroid and hormones

"Stress inhibits the thyroid gland and can lower progesterone (and/or testosterone) while increasing estrogen. Recent work by Siiteri and his group shows a hormonal involvement in various autoimmune diseases. Women are significantly more susceptible to these diseases than men."

Nutrition For Women

Dalton's findings on menopause and hormonal imbalance

"Katharina Dalton found that premenstrual symptoms resulting from a relative excess of estrogen and a deficiency of progesterone often persist during menopause."

Nutrition For Women

Increasing conversion to estrogen with age

“Siiteri and his team discovered that one of the steroids (androstenedione, which is usually associated with male hormones) is increasingly converted into a form of estrogen with age – in all age groups studied from 20 to 80 years and in both men and women.”

Nutrition For Women

Menopausal symptoms and progesterone deficiency

"Strickler found that only 10% of his patients with menopausal symptoms such as hot flashes experienced any effect from estrogen when it was administered alternately with a placebo. These studies, and several dozen others, have convinced me that menopausal symptoms are primarily due to a progesterone deficiency relative to estrogen. The 10% who actually feel better with estrogen may have an estrogen deficiency, but this is not definitively proven, and several other factors could explain the perceived well-being—for example, a healthy thyroid may respond to increased estrogen with increased thyroxine production, which at the very least leads to a different feeling of well-being and may possibly raise blood sugar and increase alertness."

Nutrition For Women

Nutritional needs for regulating estrogen and thyroid function

"In addition to the nutrients required to regulate estrogen levels (protein and B vitamins), as well as the nutrients necessary for the thyroid gland (e.g., iodine, manganese, and cobalt), special attention should be paid to the anti-stress vitamins involved in progesterone synthesis (vitamin A, pantothenic acid, vitamin C, vitamin E), as well as to the nutrients known to be consumed in greater quantities by an excess of estrogen: in particular folic acid, zinc, and vitamin B6."

Nutrition For Women

Estrogen-induced adrenal gland enlargement to compensate for blood sugar levels

"It is known that an excess of estrogen causes hypertrophy of the adrenal cortex. Since estrogen stimulates insulin secretion and lowers blood sugar, this hypertrophy could serve to raise blood sugar levels again."

Nutrition For Women

Estrogen's role in water retention and loss of skin elasticity

"Women swell with water and fat under the influence of estrogen – similar to cows – and wrinkles appear to be smoothed out; in reality, however, the skin loses its elasticity more quickly under the influence of estrogen."

Nutrition For Women

Estrogen's contribution to heart attacks and magnesium deficiency

"Estrogen causes heart attacks instead of preventing them. It leads to a magnesium deficiency, which promotes blood clotting."

Nutrition For Women

Critical perspectives on long-term estrogen therapy

"Constance Martin writes in her Textbook of Endocrine Physiology (1976) that estrogens are not beneficial when used long-term. M.R. Urist (in Biochemistry and Physiology of Bone , Vol. 2, ed. by G.H. Bourne, 1972) explains that estrogen does not restore bone mass to an extent detectable by X-ray, that an excess of growth hormone can worsen the disorder, and that estrogen stimulates the release of growth hormone."

Nutrition For Women

The debate about the effectiveness of estrogen in the treatment of osteoporosis

"The argument for using estrogen to cure or prevent osteoporosis rests on the fact that estrogen reduces calcium excretion in urine. Vitamin E deficiency (and estrogen is known to increase the need for vitamin E) leads to calcium being retained in the muscles. Indeed, any kind of toxin causes calcium retention in soft tissue—for example, the heart absorbs calcium when it is suffering from oxygen deprivation. However, since no improvement in bone structure can be demonstrated by X-rays, I suspect that the increased calcium storage is simply a toxic effect of estrogen."

Nutrition For Women

Estrogen accumulation due to stress-induced liver sluggishness

"All types of stress tend to make the liver sluggish. The liver normally removes toxins and excess hormones from the body. When the liver is not functioning properly, estrogen can accumulate in high amounts. One effect of estrogen is to promote a type of oxidation that does not provide energy, thereby increasing oxygen demand."

Nutrition For Women

Estrogen's role in the inhibition of coagulation-dissolving enzymes

"Another effect of estrogen is to inhibit a proteolytic enzyme in the blood that normally dissolves blood clots. For this reason, birth control pills can cause blood clots, strokes, and other circulatory problems."

Nutrition For Women

Vitamin E as a protective factor against excess estrogen effects

"Vitamin E promotes oxidative processes in various ways and appears to specifically counteract many of the effects of excess estrogen. For example, it can protect the liver from damage caused by toxins (although, of course, all nutrients are important for the liver). It counteracts estrogen's tendency to produce age spots. In addition, it activates blood protease, thereby accelerating the breakdown of blood clots and preventing their formation in blood vessels, while simultaneously apparently supporting normal blood clotting in the event of injury."

Nutrition For Women

Magnesium's role in preventing blood clots and maintaining vascular health

"Magnesium acts against calcium (and estrogen) in the coagulation system, can prevent vascular spasms and helps to conserve oxygen."

Nutrition For Women

Effects of a low-protein diet on estrogen detoxification by the liver

"Low-protein diets clearly impair the liver's ability to detoxify estrogen and other stressors."

Nutrition For Women

Relationship between estrogen levels and blood pressure fluctuations

"For several years I had suspected a link between estrogen and low blood pressure, based solely on the observation that women with seemingly high estrogen levels tended to have below-average blood pressure."

Nutrition For Women

Potential therapeutic use of thyroxine in aging, radiation sickness and cancer

"Since aging and X-rays share some biochemical effects with those of estrogen, they could also counteract thyroxine; this suggests that high doses of thyroxine could be used for age-related conditions, radiation sickness, and cancer."

Nutrition For Women

Zinc deficiency in connection with excess estrogen and its nutritional consequences

"A zinc deficiency is often associated with a deficiency of vitamin B6 and an excess of copper; since estrogen is associated with a loss of zinc, other nutrients such as vitamin E and folic acid should also be considered if white spots appear on the nails."

Nutrition For Women

Nutritional needs under the influence of estrogen to maintain blood sugar levels and for a healthy pregnancy

"Vitamin E, vitamin A, and magnesium also help maintain blood sugar levels. Vitamin B12 is needed to utilize vitamin A. Folic acid, vitamin B6, and zinc are consumed in greater quantities due to increased estrogen and are particularly important for a healthy pregnancy. Too much copper can lower blood sugar; too much iron can destroy vitamin E, and a vitamin E deficiency can lead to jaundice, which can affect the baby's brain."

Nutrition For Women

Central regulation of estrogen and its connection with important bodily factors

"Estrogen is centrally – or crucially – regulated by the liver. Estrogen, progesterone, iodine, sugar, and stress are closely linked."

Nutrition For Women

Dietary adjustments when taking various medications, including estrogen

"Every medication alters nutritional needs. Tobacco, iron, aspirin, estrogen, tranquilizers, and diuretics must be taken into account. Special diets exist for specific needs."

Nutrition For Women

Estrogen levels after removal of the ovaries in rat studies

"In rat studies, serum estrogen levels returned to normal within one week after removal of the ovaries, as all parts of the body produce estrogen."

November 2020 – Ray Peat's Newsletter

Aromatase activity and hormonal effects in menopause

"Aromatase, the enzyme that produces estrogen, is present in muscles, adipose tissue, blood vessels, and many other tissues, and its activity is increased by cortisol and decreased by progesterone. The altered activity of these two steroids during menopause may explain the sudden increase in degenerative diseases, inflammation, depression, etc."

November 2020 – Ray Peat's Newsletter

Effects of menopause on respiratory and circulatory health

"Respiratory and circulatory problems increase with menopause, corresponding to a rise in inflammatory cytokines and cortisol, as well as a decrease in progesterone and thyroid hormone. Both thyroid hormones and progesterone have a thermogenic effect and lower estrogen levels."

November 2020 – Ray Peat's Newsletter

Cellular stress responses and their long-term consequences

"Part of the basic cellular defense response involves enzymes that process toxins in a way that improves the immediate situation, but which, if chronically activated, can create new problems for the organism. For example, stressed tissues produce carbon monoxide and estrogen, which inhibit apoptosis and promote autophagy, ensuring short-term survival. Under the influence of carbon monoxide and estrogen, cells survive the stress, but produce cytokines that alter the sensitivity of neighboring cells to stress and inflammation, and gradually undergo epigenetic changes, causing them to tend to transform into a different cell type."

November 2017 – Ray Peat's Newsletter

TNF, interferon and estrogen in early embryonic development

“In the early embryo, where no pathogens are present, TNF and interferon are nevertheless present and act as regulators of cell development and differentiation (Li et al., 2014). Estrogen is involved in the embryonic determination of dorso-ventral polarity (Carroll et al., 2014). In the absence of pathogens, these inflammatory signals function as morphogens, as connecting elements in the organismic field.”

November 2016 – Ray Peat's Newsletter

Early research on the harmful effects of estrogen

"Almost immediately after purified estrogen became available for research in the 1930s, its ability to cause inflammation, cancer, miscarriages, and seizures was recognized."

November 2016 – Ray Peat's Newsletter

Stress affects estrogen and progesterone

"Damage to the ovaries or systemic stress leads to a decrease in progesterone production, while the body's own production of estrogen increases."

November 2016 – Ray Peat's Newsletter

Vicious cycle of estrogen and inflammation

"Free fatty acids enhance the effects of estrogen and increase the production of inflammatory prostaglandins, which activate aromatase. Since estrogen increases lipolysis and free fatty acids, as well as promoting their conversion into prostaglandins, this stress-induced process easily becomes a self-perpetuating vicious cycle."

November 2016 – Ray Peat's Newsletter

Thymus atrophy: causes and regenerative factors

“Factors that cause thymus atrophy include cortisol and other glucocorticoid hormones, estrogen, prostaglandins, polyunsaturated fatty acids, lipid peroxidation, nitric oxide, endotoxin, hypoglycemia, and ionizing radiation. Progesterone and thyroid hormones support thymus restoration by providing protection through counteracting all of these atrophy-causing factors. Increasing dietary sugar intake may correct some of the metabolic changes associated with aging.”

November 2016 – Ray Peat's Newsletter

Progesterone's role as a calcium channel blocker

"Progesterone and its neuroactive metabolites, including tetrahydroprogesterone or allopregnanolone, are highly effective calcium channel blockers (Todorovic et al., 2004; Pathirathna et al., 2005; Hu et al., 2007). One of the main functions of progesterone is the inactivation of the estrogen receptor; estrogen and its receptor are strong activators of cellular calcium uptake."

May 2020 – Ray Peat's Newsletter

Estrogen, serotonin, and manipulation by the pharmaceutical industry

"The pharmaceutical industry's manipulation of information about estrogen was even more extreme than its handling of serotonin. Activated by stress, it is, along with serotonin, one of the most important activators of corticotropin-releasing hormone (CRH), which activates the pituitary gland and adrenal glands, promotes inflammation, and is a key factor in postpartum depression (Glynn and Sandman, 2014; Hahn-Holbrook, 2016) as well as in other forms of depression, aging, and Alzheimer's disease."

May 2019 – Ray Peat's Newsletter

CRH, aromatase and hormone interactions

“CRH activates aromatase, creating a potential vicious cycle, but progesterone can prevent this effect (Roy et al., 1999). CRH inhibits progesterone production while simultaneously increasing estrogen.”

May 2019 – Ray Peat's Newsletter

Estrogen increases serotonin synthesis in the brain.

"Estrogen increases the brain's ability to synthesize serotonin."

May 2019 – Ray Peat's Newsletter

Estrogen, serotonin, and common female-specific diseases

"If it weren't for advertising culture, it would probably be generally accepted that both estrogen and serotonin play an important role in the development of depression, migraines and Alzheimer's disease – all conditions that are significantly more common in women than in men."

May 2019 – Ray Peat's Newsletter

Estrogen, progesterone and animal connective tissue

"AV Everitt reviewed studies on rabbits that showed that the body's own estrogen during pregnancy increased the stiffness of their connective tissue, while the persistently increased progesterone production between litters reversed this effect. It was found that the connective tissue of animals that had had many litters appeared younger than that of animals of the same age that had never reproduced."

May 2019 – Ray Peat's Newsletter

Prenatal estrogen and its effects on brain size

"Prenatally, an excess of estrogen inhibits cell growth, resulting in a smaller brain at birth with a thinner cerebral cortex. In adult animals, it can cause seizures and excitotoxic cell death."

May 2019 – Ray Peat's Newsletter

Postpartum progesterone and brain health

"With insufficient cholesterol, the normally high postpartum progesterone concentration cannot be maintained, and instead of the brain's recovery, the various pro-inflammatory effects of serotonin and estrogen predominate, with consequences such as depression, joint pain, anxiety, and cerebral edema."

May 2019 – Ray Peat's Newsletter

Stress, metabolic energy and system integration

"In good health, the stimulation of CRH production by histamine, serotonin, endorphins, IL-1, nitric oxide, and/or estrogen leads to the activation of complex and appropriate anti-stress responses. However, if stress is very intense or prolonged, or if nutrition has been inadequate, all these activating signals—as well as CRH itself and the anti-stress glucocorticoids—can produce effects that are no longer integrated into the organism's functions as it meets its challenges. This results in symptoms and ultimately degenerative processes and aging. This failure of integration is almost always the consequence of insufficient metabolic energy."

May 2019 – Ray Peat's Newsletter

Estrogen, aging and water content of uterine tissue

"In connection with my doctoral thesis, I found that the water content of uterine tissue was influenced by both estrogen and aging."

March 2020 – Ray Peat's Newsletter

Oxidative processes and factors of enzyme regulation

"The oxidative processes that support the targeted, creative functioning of the organism optimize CO₂ by inhibiting carbonic anhydrase; this enzyme is inhibited by the thyroid hormone T3, progesterone, urea, caffeine, antipsychotics, and aspirin. Substances that tend to cause a return to primitive anaerobic energy production activate this enzyme—including serotonin, tryptophan, cysteine, histamine, estrogen, aldosterone, HIF, SSRIs, angiotensin, and parathyroid hormone."

March 2020 – Ray Peat's Newsletter

Silicon dioxide, estrogen and lactic acid production

"Small particles of silicon dioxide or other inorganic or organic materials (such as plastics) can – similar to radiation, oxygen deficiency, sepsis or estrogen – increase the production of lactic acid, and this lactate promotes various features of inflammation, including edema, collagen synthesis, and the growth and movement of cells."

March 2019 – Ray Peat's Newsletter

Radiation, matter, and the reductive stress of estrogen

“Ionizing radiation, particulate matter and an excess of estrogen disrupt the system in different ways, but all lead to reductive stress, inflammation, collagen synthesis and the loss of differentiated cell functions.”

March 2019 – Ray Peat's Newsletter

Stress causes a decrease in testosterone and an increase in estrogen.

"In men, testosterone levels decrease due to stress and aging, and its conversion to estrogen is increased by stress and inflammation. Endotoxin specifically increases the conversion of testosterone to estrogen."

March 2017 – Ray Peat's Newsletter

Age-related brain changes are exacerbated by estrogen.

"With increasing age, iron and polyunsaturated fatty acids accumulate in the brain. Estrogen slows the breakdown of dopamine, thereby increasing the likelihood of it reacting toxically with iron and highly unsaturated fatty acids, especially arachidonic acid and DHA; it also promotes the formation of prostaglandins and nitric oxide. The opposing effects of progesterone likely explain the lower incidence of Parkinson's disease in women compared to men."

March 2017 – Ray Peat's Newsletter

Dihydrotestosterone may be more effective than testosterone

"Treatment with dihydrotestosterone (which cannot be converted into estrogen) could be more effective than with ordinary testosterone, taking into account the increased activity of aromatase with age, stress and inflammation, as well as the likely role of estrogen in the excitatory degenerative process."

March 2017 – Ray Peat's Newsletter

Protective factors in Parkinson's disease generally counteract estrogen.

"Things that are likely to be protective in Parkinson's disease are generally also protective against estrogen and inflammatory-degenerative processes: progesterone, minocycline and other anti-inflammatory antibiotics, agmatine, aspirin, coffee, niacinamide, citrus flavonoids, vitamin D, ACE inhibitors, and high-fiber, antiseptic foods."

March 2017 – Ray Peat's Newsletter

Serotonin, cortisol and estrogen interactions

"Serotonin activates stress hormones, and the resulting cortisol can have a protective effect by inhibiting the enzyme that produces serotonin and activating the MAO that breaks it down (Clark and Russo, 1997; Ou et al., 2006; Popova et al., 1989). Estrogen increases serotonin synthesis, reduces its binding, and inhibits its breakdown."

July 2019 – Ray Peat's Newsletter

Serotonin, MAO and hormonal effects on the lungs

"If something (such as smoking, very high oxygen concentrations, or a hormonal imbalance) inhibits MAO activity, the high local activity of serotonin can cause pulmonary edema, decreased blood oxygen saturation, pulmonary fibrosis, and pulmonary arterial hypertension. Estrogen is an important inhibitor of MAO in the vascular endothelium; progesterone has the opposite effect and increases MAO activity."

July 2019 – Ray Peat's Newsletter

Ideology distorts the understanding of stress physiology

"The ideology surrounding stress physiology, which distorts the importance of serotonin, estrogen, unsaturated fatty acids, sugar, lactate, carbon dioxide and various other biological molecules, has hidden the simple cures for most inflammatory and degenerative diseases."

July 2019 – Ray Peat's Newsletter

Estrogen receptor function independent of estrogen

"The so-called estrogen receptor can also be active without the presence of estrogen if the cell is stressed by hypoxia, ionizing radiation or inflammation, whereby factors that damage the cell can supplement the existing estrogen."

July 2018 – Ray Peat's Newsletter

Protective effects of various substances against estrogen effects

"Aspirin, vitamin E, and progesterone protect against a wide range of harmful factors, in addition to their various antagonistic effects on the estrogen system itself. One of the main effects of progesterone is to suppress or reduce the estrogen receptor."

July 2018 – Ray Peat's Newsletter

Various substances increase respiration and decrease essential CO₂

"Besides ammonia and lactate, other stress-related substances can also increase respiratory drive and thereby reduce essential CO₂ – including endotoxin, acetylcholine, serotonin, hydrogen sulfide, nitric oxide, carbon monoxide, angiotensin and estrogen."

July 2017 – Ray Peat's Newsletter

Reductive stress triggers restorative cellular processes.

“Reductive stress activates several levels of restorative processes (alternatives to the protective functions of carbon dioxide) to stimulate respiration, increase blood flow, and provide energy and materials for the renewal of cellular structures. Prostaglandins, cytokines, estrogen, and nitric oxide are produced in a coordinated manner, and cell behavior changes in a defensive way. The structures of the cytoskeleton are altered as reductive chemistry converts protein disulfides into sulfhydryls, thereby changing the shape and—most importantly—the solubility properties of the cellular material.”

July 2017 – Ray Peat's Newsletter

Common inhibitors of the enzyme carbonic anhydrase

"Common inhibitors of carbonic anhydrase include mildly oxidizing flavonoids such as apigenin and fisetin, some polyphenols, vitamin B1, vitamin D (Mras et al., 2012), progesterone (partly by blocking activation by estrogen and aldosterone) and emodin."

July 2017 – Ray Peat's Newsletter

Enzymatic destruction of active hormones

"The active thyroid hormone T3 is broken down locally by a specific deiodinase, prostaglandins are produced by cyclooxygenase, estrogen by aromatase, and nitric oxide by its synthase. These enzymes are activated by chemical reduction of their disulfide groups, which are converted into thiol groups."

July 2016 – Ray Peat's Newsletter

Estrogen vs. progesterone – opposing metabolic effects

"Estrogen has an excitatory effect, comparable to an excessive increase in temperature, and shifts energy production towards glycolysis as well as cell functions towards dedifferentiation and cancer metabolism, while progesterone has opposite effects: It reduces excitation, lowers energy demand, shifts energy production away from inefficient glycolysis and can restore normal differentiation while simultaneously reversing features of cancer."

January 2021 – Ray Peat's Newsletter

Rapid cellular effects of thyroid hormone and estrogen

"It has been observed that the active thyroid hormone increases the oxygen consumption of the cells almost immediately, while estrogen increases the uptake of sugar and water into the cells just as quickly. These changes occur far too rapidly to be the result of communication with the cell nucleus leading to the synthesis of new proteins."

January 2019 – Ray Peat's Newsletter

Catalytic function of estrogen: A study

"Evidence of a catalytic function of estrogen was provided by a research group at the University of Chicago (Talalay et al., 1958), who showed that it acts as a transhydrogenase."

January 2019 – Ray Peat's Newsletter

Hormones alter enzyme activity

"Besides their metabolism in the uterus and other target tissues, it is now well known that estrogen and other hormones can alter the activity of enzymes without being directly involved as catalysts in the reaction and without initially acting in the cell nucleus."

January 2019 – Ray Peat's Newsletter

Estrogenic effects can be mimicked without the molecule itself.

"The effects of estrogen can be induced in various ways, even without the estrogen molecule itself. An excess of intracellular water, similar to the water that cells absorb immediately after estrogen stimulation, is sufficient to mimic its effects. In the absence of oxygen, cells absorb water, and the estrogen receptors behave as if they had been activated by estrogen – but without the estrogen molecule."

January 2019 – Ray Peat's Newsletter

Several factors act synergistically with estrogen.

“Many different factors – X-rays, hypoglycemia, excessive alkalinity, cyanide, cholera toxin – act synergistically with estrogen; they obviously do not act solely via estrogen receptors.”

January 2019 – Ray Peat's Newsletter

Antagonistic effect of progesterone on other steroid hormones

"The effects of progesterone are antagonistic to those of the other important steroid hormones, especially estrogen, cortisol, and aldosterone. These hormones impair energy metabolism, particularly the oxidation of glucose."

January 2018 – Ray Peat's Newsletter

Environmental enrichment lowers estrogen and glucocorticoids.

"Both estrogen and stress-induced glucocorticoids are reduced by environmental accumulation, allowing progesterone to function with less interference."

January 2018 – Ray Peat's Newsletter

Estrogen, injury and energy metabolism

"The remarkable fact that both estrogen and nitric oxide are produced in virtually every injury has rarely been mentioned, and their closely related effects on energy metabolism have generally been ignored."

January 2016 – Ray Peat's Newsletter

Estrogen's disruption of oxidative metabolism for reproduction and repair

"A substance like estrogen is able to interrupt oxidative metabolism in order to initiate the organism's reproduction or to stimulate tissue repair in response to local injury."

January 2016 – Ray Peat's Newsletter

Estrogen-induced respiratory depressants and their effects

"One of the respiratory-inhibiting substances produced by estrogen is carbon monoxide (Tschugguel et al., 2001). Another inhibitor of mitochondrial oxidation, hydrogen sulfide, is also increased by estrogen (Lechuga et al., 2015)."

January 2016 – Ray Peat's Newsletter

Epigenetic changes through stress adaptation

"In all these states of stress adaptation, epigenetic modifications of DNA are involved, with nitric oxide, along with estrogen and other hormones, participating in DNA methylation and histone modification, as well as a variety of other biochemical, persistent changes."

January 2016 – Ray Peat's Newsletter

Progesterone improves thyroid function against estrogen.

"Progesterone also enables the thyroid gland to secrete its hormones, especially when thyroid function has been inhibited by estrogen."

Generative Energy Restoring The Wholeness Of Life

Fundamental role of progesterone and DHEA

"Progesterone and DHEA are the precursors of the other, more specialized steroid hormones, including cortisol, aldosterone (the sodium-retaining hormone), estrogen and testosterone."

Generative Energy Restoring The Wholeness Of Life

Concerns regarding the administration of DHEA without hormonal balance

"Since DHEA can easily be converted into testosterone (for example, through the skin) and into estrogen, I consider it problematic to ever administer it alone – without a near-natural balance of pregnenolone and progesterone."

Generative Energy Restoring The Wholeness Of Life

Estrogen and prolactin impair breathing.

"Estrogen and prolactin cause many things that affect breathing."

Generative Energy Restoring The Wholeness Of Life

Possible role of endorphins in symptoms of ovarian cancer

"I think that excess endorphins are often the problem and that an antagonist can sometimes be helpful. Endorphins differ in their effects on the two sides of the body, so when I knew two women (in the same year) who had puzzling one-sided symptoms for several months before being diagnosed with ovarian cancer (each on the same side), I suspected that endorphins were probably involved—possibly to suppress pain on that side. Naloxone and naltrexone have some effects that are not directly related to endorphins, but rather to estrogen and histamine."

Email reply from Ray Peat

Aging and the role of estrogen in the availability of reactive electrons

"In my experiments, I found that both aging and estrogen stimulation led to a strong increase in the availability of reactive electrons, which I measured by their reaction with a dye. These electrons originate from an interactive system that includes proteins (cysteine) and glutathione, as well as various cofactor catalysts such as ascorbic acid and NADH."

February 2001

Catalytic redox function of estrogen and historical perspectives

"In the 1950s, several endocrinologists gathered evidence that estrogen could act as a catalyst in the oxidation and reduction of the pyridine nucleotides NADPH and NADH. However, in the 1960s, the idea that the effects of estrogen were mediated exclusively via the estrogen receptor began to displace all other concepts of estrogen chemistry and physiology."

February 2001

Estrogen as a redox catalyst in the generation of toxic radicals

“JG Liehr and several others further demonstrate that estrogen can act as a catalyst in the redox cycle (alternating reduction and oxidation), generating toxic free radicals and potentially burdening NADH systems. In its function as a redox catalyst, estrogen oscillates between an oxidized and a reduced molecular form. In this context, the ratio of the different estrogen forms takes on a completely different significance than merely their differing effects on the so-called estrogen receptors.”

February 2001

Estrogen and its interaction with albumin during uptake into brain cells

"Protein-bound estrogen is an active form of estrogen, and albumin-bound estrogen likely accounts for the majority of estrogenic activity. Free fatty acids, competing with estrogen for binding to steroid-binding globulin, probably alter the properties of the abundant albumin so that it binds more estrogen in its active form. This shifts estrogen from other proteins, lipoproteins, and red blood cells to activated albumin. The presence of fats bound to albumin makes the albumin more lipophilic, or fat-loving, and molecules are taken up into cells according to their fat solubility—especially brain cells. There is no blood-brain barrier for fat-soluble molecules."

February 2001

Estrogen levels and anti-estrogenic factors in reproduction

"Actual estrogen levels rise throughout the reproductive years, and with menopause, the decrease in anti-estrogenic factors such as progesterone, thyroid hormone, and DHEA leads to an increased effect of estrogen."

February 2001

Estrogen, PUFAs and insulin resistance in diabetes

"Estrogen and polyunsaturated fatty acids (PUFAs) create insulin resistance, and the resulting state of diabetes and stress depletes tissues of energy."

February 2001

Estrogen's role in cortisol production and cell damage

"An elevated cortisol level is a normal response to the cell-damaging effects of stress or inflammation, but cortisol itself causes the death of nerve and immune cells through excitotoxicity by blocking glucose metabolism. Estrogen increases cortisol production in several ways, both via the pituitary gland and directly via the adrenal glands."

February 2001

Potency of estradiol and influence of estrone on mental performance

"Although estradiol is the most potent estrogen, estrone is the predominant estrogen in the bloodstream by quantity, and it has been found that women's mental performance was lower when estrone levels were higher."

February 2001

Unique receptor behavior of estrogen and its tissue interaction

"The effect of estrogen on many tissues increases their ability to bind estrogen; estrogen induces its own receptor in a self-stimulating, self-destabilizing process. This differs from the behavior of other receptors, such as the adrenaline receptor, which is inactivated by increased adrenaline exposure. This unusual tissue-hormone interaction requires careful consideration."

March 2000

Progesterone as a defense against estrogen

"By reducing the cell's ability to bind estrogen, progesterone acts as a defense against estrogen."

March 2000

Influence of estrogen on cellular stimulation responses

"Is the specific outcome of stimulation determined by estrogen, or rather by the way in which estrogen is neutralized and detoxified?"

March 2000

Evolutionary role of estrogen and anti-estrogenic strategies

“Since excitation or stress is fundamental—namely, any disturbance of the resting state of a living system—radiation damage, suffocation, nutrient deficiencies, various toxins, carcinogens, and irritants can mimic the effects of estrogen. Or, put another way, in its evolutionary significance, estrogen mimics the natural threats to which life is exposed, allowing the processes of regeneration to be controlled and integrated into the life strategies of organisms. This means that anti-estrogenic strategies are appropriate under a wide variety of conditions. Regardless of the challenge, a successful response will restore the organism to a new state of high energetic readiness.”

March 2000

Dynamics of estrogen and progesterone in organismic imbalance

"All the knowledge accumulated about estrogen over the last century leads to the conclusion that it serves the organism by creating a momentary and local imbalance and stimulating cellular activity. An important factor in the integration of this temporary imbalance into the organism's life is the way in which destabilizing excitation and the restoration of stability—that is, estrogen and progesterone production—are related. Estrogen stimulates the production of progesterone, and progesterone lowers the concentration of estrogen."

March 2000

Free fatty acids and their influence on glucose oxidation and diabetes

"An increase in free fatty acids suppresses the oxidation of glucose. (This is known as the Randle effect, glucose-fatty acid cycle, or substrate-competition cycle.) Women generally have more free fatty acids than men due to higher estrogen and growth hormone levels and oxidize a greater proportion of fatty acids during physical activity. This increased fatty acid exposure reduces glucose tolerance and undoubtedly explains the higher prevalence of diabetes in women."

July 2000

Estrogen's role in the mobilization of free fatty acids and in edema

"Adrenaline mobilizes free fatty acids from tissues, including fat and muscle tissue. Estrogen itself also leads to increased free fatty acids. If these free fatty acids are unsaturated, they cause edema by making blood vessels more permeable."

January 2000 - Ray Peat's Newsletter

Estrogen excess and its effects on albumin synthesis

"An excess of estrogen suppresses the liver's ability to synthesize albumin, and when this is combined with the leakage of albumin into the tissues (where it is slowly broken down) and into the urine, the blood loses its ability to bind sodium, a large proportion of which is bound to albumin."

January 2000 - Ray Peat's Newsletter

Estrogen-related edema and its physiological effects

"Since a hypotonic solution mimics the effects of estrogen, and substances that make tissues permeable—such as cholera toxin—act similarly to estrogen in the uterus, the edema caused by estrogen itself appears to be a central component of its normal physiological effect."

January 2000 - Ray Peat's Newsletter

Estrogen's influence on histamine, serotonin, and edema

"Histamine, serotonin, and other inflammatory factors released by estrogen are known to contribute to its ability to cause edema. The excess nitric oxide produced under the influence of estrogen is thought to contribute to some edematous, inflammatory, and degenerative conditions."

January 2000 - Ray Peat's Newsletter

Estrogen-induced tissue swelling and non-genomic effects

"Since these effects of estrogen on tissue water are considered non-genomic and to some extent independent of normal estrogen receptors and response elements, presumably any tissue is susceptible to estrogen-induced swelling – as well as to swelling caused by unsaturated fats and a lack of carbon dioxide."

January 2000 - Ray Peat's Newsletter

Antiestrogens and their role in protecting against tissue stress

"If estrogen can cause edema in any tissue, then anti-estrogens like progesterone can probably protect against stress in any tissue."

January 2000 - Ray Peat's Newsletter

Estrogen release in inflamed tissue and neurotoxicity

"In any inflamed tissue, the enzyme beta-glucuronidase is activated, and this enzyme releases estrogen within the irritated cell, thereby triggering a further sequence of neurotoxic processes."

December 1999 – Ray Peat's Newsletter

Estrogen's controversial role in the treatment of prostate cancer

"Since it was known that estrogen treatment is dangerous for men and increases blood clotting and vascular spasms, there must have been an overarching belief that led to its widespread use in the treatment of prostate cancer. This belief seems to be that estrogen – the female hormone – counteracts testosterone, the male hormone, which is supposedly responsible for the growth and thus the development of cancer in the prostate. Everything about this statement is wrong, yet every single one of these assumptions can be found in the medical literature."

May 1998 - Ray Peat's Newsletter

Estrogen increase in men with age and under stress

"It was recognized decades ago that estrogen levels in men increase with age (Pirke and Doerr, 1975), as well as in cases of stress, illness, malnutrition and hypothyroidism – conditions that are also associated with aging."

May 1998 - Ray Peat's Newsletter

Estrogen production in adipose tissue and age-related increase

“Estrogen is produced in adipose tissue (Stierti and MacDonald, 1973; Vermeulen, 1976), which tends to increase with age when thyroid hormone and progesterone levels are reduced.”

May 1998 - Ray Peat's Newsletter

Conversion of testosterone to estrogen in adolescent boys

"The conversion of testosterone to estrogen takes place in the testicles themselves, but is inhibited by the favorable hormonal environment of youth."

May 1998 - Ray Peat's Newsletter

Antagonism between estrogen and vitamin A in cell proliferation

"The antagonism between estrogen and vitamin A in the control of epithelial cell proliferation (and possibly other cell types; Boettger-Tong and Stancel, 1995) is clearly evident wherever it has been studied; vitamin A inhibits epithelial proliferation."

May 1998 - Ray Peat's Newsletter

Environmental estrogens and their effects on wildlife and human health

"Environmental estrogens are clearly responsible for genital malformations and infertility in many wild animal species, but when the causal link between estrogens and human malformations is established, the estrogen industry sends its mouthpieces to sow controversy and confusion."

May 1998 - Ray Peat's Newsletter

Estrogen effects in wastewater and secret studies

"Even the effects of estrogens in wastewater, which have been known for decades, are treated like state secrets: There were reports of hermaphroditic fish in one or two rivers, and state investigators had been looking into this since the late 1970s. But nobody knew about this work because it was classified. (Lutz, 1996.)"

May 1998 - Ray Peat's Newsletter

Hormonal influences on prostate cell division

"In human prostate tissue sections, several hormones—including insulin and presumably prolactin—stimulated cell division; testosterone, however, did not do so under these experimental conditions (McKeehan et al., 1984). Contrary to popular belief, there is evidence that complementary androgens could control prostate cancer (Umekita et al., 1996) and that antagonists of prolactin and estrogen could potentially be used effectively in hormone therapy."

May 1998 - Ray Peat's Newsletter

Hormonal changes in men aged 50 with prostate enlargement

"Around the age of 50, men often show an excess of prolactin and estrogen, as well as a deficiency of thyroid hormones and testosterone. At this age, an enlarged prostate often becomes clearly noticeable for the first time."

May 1998 – Ray Peats Newsletter

Interactions between free fatty acids and estrogen in metabolism

"Estrogens lead to an increase in free fatty acids, and there are many interactions between unsaturated fatty acids and estrogen, including their metabolism to prostaglandins and their peroxidation."

May 1998 – Ray Peats Newsletter

Role of unsaturated fatty acids in enhancing estrogen effects

"Unsaturated fatty acids, but not saturated fatty acids, release estrogen from the serum proteins that bind it, thereby increasing its availability and effect in tissue cells."

May 1998 – Ray Peats Newsletter

Estrogen's interaction with porphyrin metabolism

"The heme group (for example, of hemoglobin and respiratory enzymes) is the iron-binding, fat-soluble molecule that interacts with oxygen and is called porphyrin. There is a long history of research investigating the interactions between porphyrin metabolism and estrogen."

1997 – Ray Peat's Newsletter

Estrogen's role in porphyria and premenstrual symptoms

"It is known that estrogens trigger porphyria (RD Levere, Blood 28, 569–572, 1966) and exacerbate the symptoms and biochemical disturbances in people with subclinical porphyria. Sometimes symptoms occur premenstrually, during the phase of increased estrogen production – the term ovulocyclic porphyria has been used for a long time."

1997 – Ray Peat's Newsletter

Estrogen, testosterone and the dynamics of blood cell formation

"At a certain point, the continued production of red blood cells can make the blood so viscous that this increased viscosity impairs capillary circulation, creating a vicious cycle that stimulates the production of even more red blood cells. Men are more likely than women to have polycythemia rubra vera, possibly because testosterone has an anabolic effect on the bone marrow, while estrogen tends to slow down blood cell production."

1997 – Ray Peat's Newsletter

Similarity of estrogen to aging processes in cellular calcium uptake

"Oxygen deficiency causes tissues to retain calcium (and iron); in many cases, estrogen has a similar effect, mimicking aging by promoting cellular calcium uptake. Since porphyrins strongly bind metals, it has been suggested that they may play a role in mediating the deposition of metals in stressed tissue."

1997 – Ray Peat's Newsletter

Role of fatty residues in cell regeneration and growth

"Polezhaev's work on regeneration has suggested that the fatty residue left behind by degenerating cells stimulates the formation of new cells. Linoleic acid activates – similar to phorbol esters and estrogen – protein kinase C and the cell growth system."

September 1995 – Ray Peats Newsletter

Debunking myths about menopause: Ovarian function and hormone production

"Even people who like to claim that the ovaries don't fail during menopause describe a theory according to which menopause and its consequences result from the disappearance of egg cells in the ovaries. This theory is so simple that it can be described in three short sentences—none of which are true: (1) The ovary no longer has any egg cells; (2) ovulation produces hormones, so you notice when ovulation stops because the ovaries then no longer produce hormones; (3) menstruation stops because ovulation has stopped. Various conclusions are drawn from these basic principles. Estrogen is the female hormone. Estrogen deficiency accelerates aging. Treatment with estrogen makes one more feminine. Progesterone deficiency is the result of anovulatory cycles."