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How Hormones Shape Sexual Development — Whalespan

Content›Video›How Hormones Shape Sexual De…

How Hormones Shape Sexual Development

Andrew Huberman1h 38m · 2021-04-05

Support Rate

88%

120 of 137 claims supported

Support rate

120 of 137 claims supported

120 supported17 partial / not

Claims from this content

90

✓Well SupportedInside Tracker's platform provides actionable protocols to adjust blood markers into ideal ranges for health.✓Well SupportedHelix Sleep mattresses and pillows are tailored to individual sleep needs assessed through a quiz.✓Well SupportedThorne supplements are considered highly stringent regarding ingredient precision and quality.✓Well SupportedVitamin D3 is critical for metabolism, hormone function, and brain function, and most individuals do not get enough even with ample sunlight.✓Well SupportedIncreased obesity likely contributes to higher estrogen levels in men due to increased adipose tissue and aromatase activity.

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A. Volkovreader

4h

Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

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✓Well Supported

DHT causes facial hair growth and scalp hair loss due to genetically determined differences in receptor sensitivity and density.

✓Well SupportedCreatine supplementation may increase dihydrotestosterone (DHT).

✓Well SupportedThe D2 to D4 digit ratio is greater in self-reported females than in males, meaning D2 and D4 are more similar in length in females.

✓Well SupportedChronic marijuana use (more than twice a week) significantly reduces testosterone and elevates aromatase enzymes.

✓Well SupportedIndividuals with XY chromosomes and a mutated androgen receptor gene will develop as infertile females despite having the SRY gene and producing testosterone.

✓Well SupportedHigher prenatal androgen exposure is associated with a smaller D2 to D4 digit ratio in mice and humans.

✓Well SupportedIndividuals with a deficiency in 5-alpha reductase can appear feminized early in life and then masculinize at puberty, developing a penis.

✓Well SupportedDihydrotestosterone (DHT) is the dominant androgen in males, responsible for aggression, muscular strength, beard growth, and male pattern baldness.

✓Well SupportedA healthy gut microbiome, supported by probiotics, is vital for immune function, the gut-brain axis, brain function, mood, and limiting brain inflammation.

✓Well SupportedDuring puberty, kisspeptin stimulates GnRH and LH release, leading to testosterone production and secondary sexual characteristics.

✓Well SupportedLow libido can be caused by estrogen deficiency or excessive estrogen suppression, not just low testosterone.

✓Well SupportedThe phenomenon of increased probability of being gay with more older brothers is a reflection of more testosterone exposure in utero.

✓Well SupportedStudies suggest defects in testicular and/or ovarian development from exposure to cell phone emitted waves.

✓Well SupportedIndividuals with a mutation in the gene encoding 5-alpha reductase experienced incomplete sexual maturation and had similar muscle mass to controls.

✓Well SupportedDihydrotestosterone is responsible for the primary growth of the penis, while testosterone is involved in secondary sexual characteristics.

✓Well SupportedHormones like testosterone and estrogen have powerful organizing effects on brain development.

✓Well SupportedHormones affect the body, brain, and periphery with acute and long-term effects, including on gene expression.

✓Well SupportedAnecdotal observations suggest cannabis smokers have a higher incidence of gynecomastia.

✓Well SupportedHuman sperm counts declined from 113 million/mL in 1940 to 66 million/mL in 1990.

✓Well SupportedThe masculinization of the brain is accomplished by estrogen, not testosterone, although testosterone can be converted to estrogen by the enzyme aromatase.

✓Well SupportedTestosterone and estrogen are steroid hormones that bind cell surface receptors, enter the nucleus, and control gene expression.

✓Well SupportedTestosterone is converted to dihydrotestosterone (DHT) in the fetus by 5-alpha-reductase, which is crucial for penis development.

◐Partially SupportedDht is a critical androgen for libido, motivation, and drive.

◐Partially SupportedA sex difference in otoacoustic emissions present at birth may reflect prenatal testosterone exposure.

◐Partially SupportedDevelopment, defined as continuous change, lasts the entire lifespan from conception to death, with hormones constantly updating body functions.

◐Partially SupportedAndrostenedione is produced at high levels in female hyenas, causing enlargement of their genitalia.

◐Partially SupportedHerbicides can negatively impact sexual development at the gonadal and brain levels by disrupting hormones like testosterone and estrogen.

◐Partially SupportedThe Y chromosome contains genes that suppress the formation of Mullerian Ducts.

◐Partially SupportedAlcohol consumption can increase estrogenic activity, potentially impacting pubertal development.

◐Partially SupportedAndrostenedione was a performance-enhancing drug of abuse and was previously available over-the-counter.

◐Partially SupportedAndrogen insensitivity syndrome occurs in individuals with XY chromosomes who produce testosterone but have a mutated receptor for testosterone.

◐Partially SupportedExposure to atrazine in US sites has caused testicular abnormalities in male frogs.

◐Partially SupportedPuberty represents the most accelerated rate of physical and cognitive development in a human's life.

◐Partially SupportedThe NSDR (non-sleep deep rest) protocol from Madefor is a free resource that shares similarities with practices like yoga nidra and other forms of meditation.

◐Partially SupportedPlants can increase aromatase to convert testosterone to estrogen as a defense mechanism against animals.

◐Partially SupportedHormones impact tissue growth and development within an individual, between mother and offspring, and mediate communication between plants and animals.

◐Partially SupportedHormonal and neural effects during development guide adolescent and adult behavior, including sexual preference.

◐Partially SupportedHormones can have rapid effects, such as adrenaline increasing heart rate quickly, or slower effects like those of sex steroid hormones.

◐Partially SupportedMasculinization and feminization involve demasculinizing and defeminizing the body and brain as normal biological functions.

◐Partially SupportedIn men, the pointer finger and ring finger lengths tend to be more different than in women, especially on the right hand.

◐Partially SupportedPrenatal testosterone exposure may influence sexual orientation, potentially making individuals more likely to be attracted to women later in life.

◐Partially SupportedThe original data on aromatization of testosterone to estrogen in brain masculinization comes from human brain tissue.

◐Partially SupportedTestosterone is converted by the enzyme 5-alpha-reductase to dihydrotestosterone, which controls penis growth.

◐Partially SupportedSmoking marijuana during pregnancy can shift fetal hormone patterns towards more estrogenic outcomes.

◐Partially SupportedAndrostenedione is a prohormone to testosterone, converted by the enzyme 17-beta-hydroxy steroid dehydrogenase.

◐Partially SupportedEnvironmental factors and home products can impact hormone levels and sexual development.

◐Partially SupportedDrugs for hair loss are 5-alpha-reductase inhibitors that block testosterone conversion to DHT.

◐Partially SupportedEstrogen, aromatized from testosterone, establishes neural circuitry for masculine sexual and territorial behaviors in animals and humans.

◐Partially SupportedEvening primrose oil can promote estrogenic pathways and be absorbed transdermally.

◐Partially SupportedMetabolic factors and hormone levels can only be accurately assessed from blood and DNA tests.

◐Partially SupportedMaternal testosterone secretion in an XX fetus can lead to masculinization of certain fetal aspects.

◐Partially SupportedAthletic Greens is an all-in-one drink containing vitamins, minerals, and probiotics.

◐Partially SupportedThe ratio of normal spermatogenesis in humans decreased from 56.4% to 26.9% between 1981 and 1991, potentially due to widespread herbicide use.

◐Partially SupportedHormones have acute effects during the menstrual cycle and long-term effects on gene expression.

◐Partially SupportedA 2013 rat study showed minor defects in ovarian and testicular development when a cell phone was placed under their cage.

◐Partially SupportedDuring puberty in boys, aromatase converts some testosterone to estrogen, potentially causing breast bud development.

◐Partially SupportedStudies on androstenedione in hyenas and pseudo-hermaphroditic moles have impacted the understanding and therapeutics of clinical conditions like pseudo-hermaphroditism.

◐Partially SupportedSelective Androgen Receptor Modulators (SARMs) are compounds that act on the receptor side of hormone pathways.

◐Partially SupportedCannabis use during puberty can profoundly affect hormonal systems.

◐Partially SupportedAndrostenedione may play a role in hyena sexual development.

◐Partially SupportedEvening Primrose Oil contains estrogenic compounds and can promote estrogenic pathways, potentially causing accelerated breast development in young boys through skin contact.

◐Partially SupportedHormones require functional receptors to bind and exert their effects on target cells.

◐Partially SupportedHair loss drugs that prevent testosterone conversion to DHT can have side effects associated with low DHT levels.

◐Partially SupportedCertain herbicides can disrupt endocrine pathways.

◐Partially SupportedHormones are chemicals released from glands or neurons that travel and affect other organs and tissues.

◐Partially SupportedIn individuals with androgen insensitivity syndrome, testes do not descend and remain internal, and they do not develop a scrotum or ovaries.

◐Partially SupportedIndividuals with androgen insensitivity syndrome typically do not menstruate around puberty.

◐Partially SupportedPine pollen may act as a testosterone source, but its bioavailability in humans is unclear.

◐Partially SupportedProximity to phones, frequency of use, phone storage location, and proximity to radio-frequency towers are associated with decreases in cortisol, thyroid hormones, prolactin, and testosterone.

◐Partially SupportedIndividuals with exceedingly high levels of DHT may experience rapid maturation and early onset of baldness.

◐Partially SupportedVinclozolin, a fungicide and anti-androgen, can prevent penis formation in male rats.

◐Partially SupportedHormones have direct effects on the brain and spinal cord neurons and structures, influencing possible behaviors.

◐Partially SupportedGay men sometimes have higher testosterone levels than heterosexual men.

◐Partially SupportedThe marijuana plant produces estrogenic compounds, and some plants produce compounds equivalent to testosterone or estrogen.

◐Partially SupportedDeep, restful sleep is vital for mental and physical health.

◐Partially SupportedThere are no known quality peer-reviewed studies demonstrating harm to the brain from cell phones, holding them to the ear, or Bluetooth.

◐Partially SupportedCurrent data does not show cell phones to be harmful to the brain.

◐Partially SupportedThe placenta functions as an endocrine organ.

✕Not SupportedIndividuals undergoing testosterone replacement therapy should avoid skin contact with others, especially children, to prevent estrogenic activity.

◐Partially SupportedHormones affect behavior, and behavior affects hormones.

◐Partially SupportedDeclines in sperm counts and testosterone levels over the last 20-30 years may not be fully explained by cell phone use due to the recent widespread adoption of smartphones.

◐Partially SupportedSteroid hormones can alter gene expression, influencing cell differentiation and function long-term.

◐Partially SupportedEnvironmental toxins, cell phone radiation, Evening Primrose Oil, Creatine, cannabis, and alcohol can influence sex and sexual development.

◐Partially SupportedHigh doses of anabolic steroids can cause gynecomastia in males due to testosterone conversion to estrogen.

◐Partially SupportedHerbicides like atrazine have shown negative effects on hormone ratios and development.