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, promoting serotonin synthesis does not lead to niacinamide deficiency; however, conditions that increase estrogen's influence also exacerbate serotonin-related dysfunctions."

September 2019 – Ray Peat's Newsletter

Estrogen, Serotonin, and the Cycle of Water Retention

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

September 2019 – Ray Peat's Newsletter

Serotonin, Estrogen, and the Promotion of Pituitary Hormones

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

September 2019 – Ray Peat's Newsletter

Estrogen's Influence on Water Retention and Salt Craving

"Under the influence of excess estrogen, the body retains additional water, and normally the appetite center should balance this water by triggering a craving for extra salt. However, if salty foods are avoided during such phases (or a diuretic is taken), the blood cannot carry as much water as with sufficient salt, so the salt remains in the tissue 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 can even begin to lactate."

Nutrition For Women

Stability and Lack of Adaptability of Testosterone in Men

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

Nutrition For Women

Estrogen's Role in Cell Renewal and Response to Threats

"Estrogen is the hormone of beginnings, a kind of biochemical eraser that can delete recently stored information and restore the underlying original ability to grow. 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 induced by estrogen."

Nutrition For Women

Substances that counteract estrogen in cancer therapy

"Anything that causes tissue atrophy tends to promote cancer. The crucial question is therefore: 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, as well as vitamin E (and the closely related coenzyme Q or ubiquinone)."

Nutrition For Women

Estrogen's influence on experience and memory formation

"Arousal 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 effects on male behavior

"Stress leads to an increase in estrogen and a loss of anti-estrogens such as thyroid hormones, progesterone, and (in men) testosterone. Male monkeys that are bullied show reduced testosterone levels, and this effect lasts long even after their environment improves. The stress of submission seems to lead to an adaptation toward passivity. This passivity prevents further injury, but how stressful this continued subordination is remains unclear."

Nutrition For Women

Selye's discovery of adaptation phases and stress immunization

"Hans Selye found that the adrenal glands are an essential part of our adaptation system. In the first phase of stress, a shock reaction 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 continues until something is exhausted. By exposing rats to prior stress, Selye discovered that he could induce an adaptation to later stressors – a kind of immunization against stress."

Nutrition For Women

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

"Energetically, the estrogen-dominated metabolic state is less efficient than the oxidative state dominated by thyroid hormones and progesterone (or testosterone). The estrogen state resembles the state of learned helplessness in rats and is parasympathetically influenced, in that many chemical balances 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

Social influence on hormonal states and physiological changes

"The hormonal conditions for mild submission are changeable – 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 L. C. Strong discovered in his mice and as recently confirmed in rats exposed 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 unsupported by such valid studies but even contradicts most of the actual data available."

Nutrition For Women

Slower liver function in women and difficulties in 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 quickly enough, it accumulates – which is why male alcoholics often develop breasts. Estrogen supplements and sedatives further increase the liver's burden. Poor nutrition 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) showed that progesterone can reverse tumor growth caused by estrogen."

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Thyroid hormone and vitamin A against the effects of estrogen

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

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Estrogen-induced 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 effects on libido

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

Nutrition For Women

Synergistic effect of copper with estrogen

"Copper seems to act synergistically with estrogen and might have a similar effect."

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Vitamin E as an antiestrogen vitamin

"Vitamin E biochemically causes several effects that are exactly the opposite of what estrogen causes, which is why it has been called the antiestrogen vitamin."

Nutrition For Women

Increased vitamin E requirement due to estrogen during pregnancy

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

Nutrition For Women

Estrogen's influence on oxygen metabolism and the nervous system

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

Nutrition For Women

Endocrine interactions and the compensatory role of the thyroid against 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 probably the most important regulatory or compensatory system. When estrogen is injected into an animal, the level of thyroid-stimulating hormone rises (Brown-Grant, J. Endocr. 35, 263, 1966). This should be understood as an indication that the peripheral effect of estrogen can be compensated by thyroxine. If thyroid function is borderline, this also suggests that an increased estrogen level is not sufficiently compensated peripherally. There are many well-known examples of the metabolic or functional opposition between estrogen and thyroid hormones."

Nutrition For Women

Thyroxine's inhibitory effect on estrogen-promoted thymus atrophy

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

Nutrition For Women

Attention to iodine and electrolytes in estrogen imbalance

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

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Connection between estrogen dominance and infertility in mice through oxygen availability

"Infertility in mice is also associated with an increased ratio of estrogen to progesterone. My research showed that the likely mechanism by which an excess of 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 points to a convergence of research on reproductive aging with Warburg's theory, which states that impaired respiration is the primary defect in cancer, as well as with Selye's observation that the effect of estrogen resembles the first shock phase of the stress response."

Nutrition For Women

Estrogen causes hypoxia in various biological areas

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

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

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

Nutrition For Women

The role of progesterone in various diseases

"Even though progesterone seemingly can heal almost everything, it should only be used when the biochemical mechanism is reasonably clear. A progesterone deficiency can be mistakenly diagnosed as epilepsy, Bright's disease, multiple sclerosis, or even as estrogen deficiency (as in menopause). It can influence susceptibility to many conditions, including herpes infections, dizziness, perceptual disorders, 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 progesterone deficiency alone, but even this ratio is influenced by other factors, including age, diet, other steroids, the thyroid, and additional hormones."

Nutrition For Women

Stress, seasons, and hormone levels in humans

"Excessive stress (through 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 symptoms in a chronically affected person. Dark, cloudy winters in England or the Pacific Northwest act as strong stressors and lead to lower progesterone in women and lower testosterone in men."

Nutrition For Women

Protein deficiency in the diet as a cause of excess estrogen

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

Nutrition For Women

Dietary and hormonal influences on cellular respiration

"Various dietary, hormonal, or toxic conditions affect respiration in different ways: for example, vitamin E deficiency, excess estrogen, toxic thyroid overactivity, and DNP (the formerly popular, carcinogenic reducing agent) cause oxygen to be consumed without producing the normal amount of usable energy. A deficiency of vitamin B2 or copper can prevent oxygen utilization. Cancer (contrary to a persistent dogma) involves a defect in respiration and leads to a tendency toward hypoglycemia, which is often compensated by converting protein into sugar, ultimately leading to the wasting condition of cachexia."

Nutrition For Women

Dietary relief of tensions caused by copper or estrogen

"Tensions caused by too much copper or estrogen can be alleviated through diet. Usually, zinc supplementation is necessary – about 20 mg per day; around 30 mg of vitamin B6 has been recommended for this issue, though the amount can vary individually. Other B vitamins as well as vitamins E and A should also be used."

Nutrition For Women

Stress-related effects on the thyroid and hormones

"Stress inhibits the thyroid 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 estrogen excess and progesterone deficiency often persist during menopause."

Nutrition For Women

Increasing Conversion to Estrogen with Age

"Siiteri and his research group discovered that one of the steroids (androstenedione, commonly 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 like hot flashes felt an effect from estrogen when it was administered alternately with a placebo. These studies and several dozen others have convinced me that menopausal symptoms are mainly due to a progesterone deficiency relative to estrogen. The 10% who actually feel better from estrogen may have an estrogen deficiency, but this is not clearly proven, and several other factors could explain the perceived well-being – for example, a healthy thyroid can respond to increased estrogen with enhanced thyroxine production, which can at least lead to a different condition and 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 those necessary for the thyroid (e.g., iodine, manganese, and cobalt), special attention should be given to the anti-stress vitamins involved in progesterone synthesis (vitamin A, pantothenic acid, vitamin C, vitamin E), as well as the nutrients known to be consumed in greater amounts due to estrogen excess: especially folic acid, zinc, and vitamin B6."

Nutrition For Women

Estrogen-Induced Adrenal Enlargement to Compensate Blood Sugar

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

Nutrition For Women

Estrogen's Role in Water Retention and Loss of Skin Elasticity

"Women swell – similar to cows – under the influence of estrogen with water and fat, and wrinkles apparently smooth out; however, the skin actually loses its elasticity faster 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 that promotes blood clotting."

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Critical views on long-term estrogen therapy

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

Nutrition For Women

The debate over the effectiveness of estrogen in treating osteoporosis

"The argument for using estrogen to treat or prevent osteoporosis is based on the fact that estrogen reduces calcium excretion through urine. A vitamin E deficiency (and estrogen is known to increase the need for vitamin E) causes calcium to be retained in the muscles. In fact, any type of toxin causes calcium retention in soft tissue—for example, the heart absorbs calcium when it suffers from oxygen deficiency. However, since no improvement in bone structure can be detected by X-rays, I suspect that the increased calcium storage is merely 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 fully functional, estrogen can accumulate in high amounts. One effect of estrogen is to promote a type of oxidation that does not produce energy and thereby increases oxygen demand."

Nutrition For Women

Estrogen's role in inhibiting clot-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 seems to specifically counteract many effects of estrogen excess. 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 form age pigments. Additionally, it activates blood protease, thereby accelerating the breakdown of blood clots and preventing their formation in blood vessels, while apparently supporting normal blood clotting during injuries."

Nutrition For Women

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

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

Nutrition For Women

Effects of low-protein diets on the liver's detoxification of estrogen

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

Nutrition For Women

Connection between estrogen levels and blood pressure fluctuations

"For several years, I suspected a connection between estrogen and low blood pressure, based solely on the observation that women with apparently 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 estrogen, they might also counteract thyroxine; this suggests that high doses of thyroxine could be used for aging symptoms, radiation sickness, and cancer."

Nutrition For Women

Zinc deficiency related to excess estrogen and its nutritional implications

"Zinc deficiency is often associated with a lack of vitamin B6 and an excess of copper; since estrogen is linked to zinc loss, other nutrients like vitamin E and folic acid should also be considered when white spots appear on the nails."

Nutrition For Women

Nutritional needs under estrogen influence to maintain blood sugar and support 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 more with increased estrogen and are especially 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 key body factors

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

Nutrition For Women

Dietary adjustments when taking various medications including estrogen

"Every medication changes nutrient requirements. Tobacco, iron, aspirin, estrogen, sedatives, and diuretics must be taken into account. There are special diets for special needs."

Nutrition For Women

Estrogen levels after ovary removal in rat studies

"In rat studies, serum estrogen levels returned to normal within a week after ovary removal, 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, fat 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 rise 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 decline in progesterone and thyroid hormone. Both thyroid hormones and progesterone are thermogenic and lower estrogen levels."

November 2020 – Ray Peat's Newsletter

Cell stress responses and their long-term consequences

"Part of the basic cellular defense response includes enzymes that process toxins to improve the immediate situation but can create new problems for the organism when chronically activated. Stressed tissues produce carbon monoxide and estrogen, which prevent apoptosis and promote autophagy, ensuring short-term survival. Under the influence of carbon monoxide and estrogen, cells survive in the stressed state 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 still present and act as regulators of cell development and differentiation (Li et al., 2014). Estrogen is involved in the embryonic establishment of dorsoventral 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 effect of estrogen and increase the formation of inflammatory prostaglandins that activate aromatase. Since estrogen increases lipolysis and free fatty acids as well as their conversion into prostaglandins, this stress-induced process easily becomes a self-sustaining vicious cycle."

November 2016 – Ray Peat’s Newsletter

Thymus gland atrophy: causes and regenerative factors

"Factors causing thymus gland atrophy include cortisol and other glucocorticoid hormones, estrogen, prostaglandins, polyunsaturated fatty acids, lipid peroxidation, nitric oxide, endotoxin, hypoglycemia, and ionizing radiation. Progesterone and thyroid hormone support thymus gland restoration by providing protection against all these atrophy-causing factors. Increasing sugar intake in the diet can correct some of the metabolic changes of 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 very effective calcium channel blockers (Todorovic et al., 2004; Pathirathna et al., 2005; Hu et al., 2007). One of progesterone's main functions 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 manipulation of information about estrogen by the pharmaceutical industry 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 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 boosts serotonin synthesis in the brain

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

May 2019 – Ray Peat’s Newsletter

Estrogen, serotonin, and diseases common in women

"If advertising culture did not exist, it would probably be generally accepted that both estrogen and serotonin play an important role in the development of depression, migraine, and Alzheimer's – all conditions that occur significantly more often in women than in men."

May 2019 – Ray Peat’s Newsletter

Estrogen, Progesterone, and Animal Connective Tissue

“A. V. Everitt reviewed studies on rabbits showing 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 many litters appeared younger than that of age-matched animals that had never reproduced.”

May 2019 – Ray Peat’s Newsletter

Prenatal Estrogen and Effects on Brain Size

“Prenatally, an excess of estrogen inhibits cell growth, leading to 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 brain restoration, the various pro-inflammatory effects of serotonin and estrogen predominate, with consequences such as depression, joint pain, anxiety, and brain edema.”

May 2019 – Ray Peat’s Newsletter

Stress, Metabolic Energy, and System Integration

“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 in good health. 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 faces its challenges. This results in symptoms and eventually degenerative processes and aging. This failure of integration is almost always the result of insufficient metabolic energy.”

May 2019 – Ray Peat’s Newsletter

Estrogen, Aging, and Water Content of Uterine Tissue

“In connection with my dissertation work, I found that the water content of uterine tissue was influenced both by estrogen and by 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—in a manner 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, as well as cell growth and movement."

March 2019 – Ray Peat’s Newsletter

Radiation, Matter, and the Reductive Stress of Estrogen

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

March 2019 – Ray Peat’s Newsletter

Decrease of Testosterone and Increase of Estrogen Due to Stress

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

March 2017 – Ray Peat’s Newsletter

Age-Related Brain Changes Enhanced by Estrogen

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

March 2017 – Ray Peat’s Newsletter

Dihydrotestosterone Possibly More Effective Than Testosterone

"Treatment with dihydrotestosterone (which cannot be converted into estrogen) might be more effective than with regular testosterone, considering the increased activity of aromatase with age, stress, and inflammation, as well as the probable role of estrogen in the excitatory degenerative process."

March 2017 – Ray Peat’s Newsletter

Protective Factors in Parkinson's Generally Act Against Estrogen

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

March 2017 – Ray Peat’s Newsletter

Serotonin, Cortisol, and Estrogen Interactions

"Serotonin activates the stress hormones, and the resulting cortisol can have the protective effect of inhibiting the enzyme that produces serotonin, as well as 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 lung

“If something (like smoking, a very high oxygen concentration, or a hormonal imbalance) inhibits MAO activity, the high local activity of serotonin can cause pulmonary edema, reduced 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 remedies for most inflammatory and degenerative diseases.”

July 2019 – Ray Peat’s Newsletter

Function of the estrogen receptor independent of estrogen

“The so-called estrogen receptor can also be active without the presence of estrogen when the cell is stressed by hypoxia, ionizing radiation, or inflammation, allowing factors that damage the cell to complement 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 degrade the estrogen receptor.”

July 2018 – Ray Peat’s Newsletter

Various substances increase respiration and reduce essential CO₂

“In addition to 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 multiple 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 defensively. The structures of the cytoskeleton are altered as the reductive chemistry converts protein disulfides into sulfhydryls, 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), as well as emodin."

July 2017 – Ray Peat’s Newsletter

Enzymatic destruction of active hormones

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

July 2016 – Ray Peat’s Newsletter

Estrogen vs Progesterone – opposing metabolic effects

"Estrogen acts as a stimulant, comparable to an excessive increase in temperature, and shifts energy production toward glycolysis as well as cell functions toward dedifferentiation and cancer metabolism, while progesterone has opposite effects: It reduces stimulation, lowers energy demand, shifts energy production away from inefficient glycolysis, and can restore normal differentiation while simultaneously reversing cancer characteristics."

January 2021 – Ray Peat’s Newsletter

Rapid cellular effects of thyroid hormone and estrogen

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

January 2019 – Ray Peat’s Newsletter

Catalytic function of estrogen: A study

"Evidence for 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 activities

"In addition to their metabolism in the uterus and other target tissues, it is now well known that estrogen and other hormones can alter enzyme activity without directly acting as catalysts in the reaction and without initially acting in the cell nucleus."

January 2019 – Ray Peat’s Newsletter

Estrogen effects can be mimicked without the molecule itself

"The effects of estrogen can be triggered in various ways, even without the estrogen molecule itself. An excess of intracellular water, similar to the water cells absorb immediately after estrogen stimulation, is enough to mimic its effects. Under oxygen deficiency, cells take up water, and the estrogen receptors behave as if they were activated by estrogen – but without the estrogen molecule."

January 2019 – Ray Peat’s Newsletter

Various 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 only through estrogen receptors."

January 2019 – Ray Peat’s Newsletter

Antagonistic Effect of Progesterone Against Other Steroid Hormones

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

January 2018 – Ray Peat’s Newsletter

Environmental Enrichment Lowers Estrogen and Glucocorticoids

"Both estrogen and stress-induced glucocorticoids are reduced by environmental enrichment, allowing progesterone to act with less disruption."

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 been rarely mentioned, and their closely linked 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 capable of interrupting oxidative metabolism to initiate the organism's reproduction or to stimulate tissue repair in response to a local injury."

January 2016 – Ray Peat’s Newsletter

Estrogen-Induced Breath-Inhibiting Substances and Their Effects

"One of the breath-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 together 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 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 about administering 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 an approximately 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 impair 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. The 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 it was found that they had ovarian cancer (each on the same side), I suspected that the 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 to estrogen and histamine.“

Email response 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 come 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 can 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 are mediated exclusively through 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

„J. G. Liehr and several others continue to show that estrogen can act as a catalyst in the redox cycle (alternating reduction and oxidation), producing toxic free radicals and possibly burdening the 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 different effects on the so-called estrogen receptors.“

February 2001

Estrogen and the Interaction with Albumin in Uptake into Brain Cells

"Protein-bound estrogen is an active form of estrogen, and estrogen bound to albumin likely accounts for the majority of estrogen activity. Free fatty acids, which compete 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 the activated albumin. The presence of albumin-bound fats makes albumin more lipophilic, or fat-loving, and molecules are taken up into cells according to their fat solubility—especially in brain cells. For fat-soluble molecules, there is no blood-brain barrier."

February 2001

Estrogen Levels and Anti-Estrogenic Factors in Reproduction

"The actual estrogen level rises throughout the reproductive years, and with menopause, the decrease of anti-estrogenic factors such as progesterone, thyroid hormone, and DHEA leads to an enhanced effect of estrogen."

February 2001

Estrogen, PUFA, and Insulin Resistance in Diabetes

"Estrogen and polyunsaturated fatty acids (PUFA) generate insulin resistance, and the resulting condition of diabetes and stress deprives tissues of energy."

February 2001

Estrogen's Role in Cortisol Production and Cell Damage

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

February 2001

Potency of Estradiol and Influence of Estrone on Cognitive Performance

"Although estradiol is the most potent estrogen, estrone is quantitatively the predominant estrogen in the bloodstream, and it has been found that women's cognitive 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 interaction between tissue and hormone 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 itself, or rather by the way estrogen is neutralized and detoxified?"

March 2000

Evolutionary Role of Estrogen and Antiestrogen Strategies

"Since excitation or stress is something fundamental – namely any disturbance of the resting state of the living system – radiation damage, suffocation, nutrient deficiencies, various toxins, carcinogens, and irritants can mimic the effects of estrogen. Or put differently: In its evolutionary significance, estrogen mimics the natural threats to which life is exposed, so that the processes of regeneration can be controlled and integrated into the life strategies of organisms. This means that antiestrogen strategies are appropriate under a variety of conditions. Regardless of the challenge, a successful response will return 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 view that it serves the organism to create a momentary and local imbalance and to stimulate cells to activity. An important factor for integrating this temporary imbalance into the life of the organism is the way destabilizing excitation and the restoration of stability – that is, estrogen and progesterone production – relate to each other. Estrogen stimulates the formation of progesterone, and progesterone lowers the concentration of estrogen."

March 2000

Free Fatty Acids and Their Impact on Glucose Oxidation and Diabetes

"An increase in free fatty acids suppresses glucose oxidation. (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 larger 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 Mobilizing 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. When these free fatty acids are unsaturated, they cause edema by making blood vessels 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 tissue (where it is slowly broken down) and into the urine, the blood loses its ability to bind sodium, much of which is bound to albumin."

January 2000 – Ray Peat’s Newsletter

Estrogen-induced edema and its physiological effect

"Since a hypotonic solution mimics the effects of estrogen and substances that increase tissue permeability – such as cholera toxin – act in the uterus similarly to estrogen, the edema caused by estrogen itself appears to be a central part 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 likely contributes 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 the normal estrogen receptors and response elements, presumably every 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 every tissue, then antiestrogens like progesterone can probably protect against stress in every tissue."

January 2000 – Ray Peat’s Newsletter

Estrogen release in inflamed tissue and neurotoxicity

"In every inflamed tissue, the enzyme beta-glucuronidase is activated, and this enzyme releases estrogen within the irritated cell, 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 as well as vascular spasms, there had to be an overarching belief that led to its general use in the treatment of prostate cancer. This belief seems to be that estrogen – the female hormone – counteracts testosterone, the male hormone responsible for the growth and thus the cancer development of the prostate. Everything about this statement is wrong, yet each 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 rise in men with age (Pirke and Doerr, 1975), as well as with stress, illness, malnutrition, and hypothyroidism – conditions also associated with aging."

May 1998 – Ray Peat’s Newsletter

Estrogen production in fat tissue and age-related increase

"Estrogen is produced in fat tissue (Stiterti and MacDonald, 1973; Vermeulen, 1976), which tends to increase with age when thyroid hormone and progesterone are reduced."

May 1998 – Ray Peat’s Newsletter

Conversion of testosterone to estrogen in male youth

"The conversion of testosterone to estrogen takes place in the testis itself 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 controlling 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 impact on wildlife and human health

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

May 1998 – Ray Peat’s Newsletter

Estrogen effects in wastewater and secret studies

"Even the effects of estrogens in wastewater, known for decades, are treated like state secrets: There were reports of hermaphroditic fish in one or two rivers, and government investigators had been studying these since the late 1970s. Yet no one knew about these studies because they were 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 also prolactin – stimulated cell division; testosterone, however, did not under these experimental conditions (McKeehan et al., 1984). Contrary to common beliefs, there is evidence that supplemental androgens might control prostate cancer (Umekita et al., 1996) and that antagonists of prolactin and estrogen could possibly be usefully employed in hormone therapy."

May 1998 – Ray Peat’s Newsletter

Hormonal changes in men at 50 and 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 enlargement of the prostate often becomes noticeable for the first time."

May 1998 – Ray Peat's 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 Peat's Newsletter

Role of unsaturated fatty acids in enhancing estrogen's effect

"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 Peat's Newsletter

Estrogen's interaction with porphyrin metabolism

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

1997 – Ray Peat's Newsletter

Estrogen's role in porphyria and premenstrual complaints

"It is known that estrogens trigger porphyria (R. D. Levere, Blood 28, 569–572, 1966) and worsen symptoms as well as biochemical disturbances in people with subclinical porphyria. Sometimes complaints occur premenstrually, during the phase of increased estrogen production – the term ovulocyclic porphyria has long been used."

1997 – Ray Peat's Newsletter

Estrogen, testosterone, and the dynamics of blood cell production

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

1997 – Ray Peat's Newsletter

Similarity of estrogen to aging processes in cellular calcium uptake

"Oxygen deficiency causes tissue to retain calcium (and iron); in many cases, estrogen causes a similar effect, mimicking aging by promoting cellular calcium uptake. Since porphyrins strongly bind metals, it has been proposed that they may play a role in mediating metal deposition 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 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 Peat's Newsletter

Debunking myths about menopause: ovarian function and hormone production

"Even people who like to claim that the ovaries do not fail during menopause describe a theory that menopause and its consequences result from the disappearance of eggs in the ovary. This theory is so simple it can be described in three short sentences – none of which is true: (1) The ovary has no more eggs; (2) ovulation produces hormones, so you notice when ovulation stops because the ovaries then stop producing hormones; (3) menstruation stops because ovulation has stopped. Various conclusions revolve around these 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."