The Science of How to Optimize Testosterone & Estrogen

Introduction (00:00:00)

• Andrew Huberman introduces the Huberman Lab Podcast which delivers zero-cost science and science-based tools to the public.
• The host has a cooking burn on his face, but assures everyone that despite the mishap, both he and his dog, Costello, are fine.
• The episode is sponsored by Four Sigmatic, a company that produces a mushroom coffee that Huberman personally enjoys due to its taste and beneficial ingredients like lion's mane mushroom and Chaga mushroom.
• A promotion for Blinkist is also offered, emphasizing its utility in summarizing key concepts of books in a short format which can be read or listened to.
• Theragun, another sponsor mentioned, provides a percussive therapy device for muscle tension relief, with Huberman sharing his own positive experience.

Hormone Optimization (00:05:50)

• The podcast will focus on hormone optimization, specifically regarding estrogen and testosterone.
• Hormones are highlighted for their significant influence on mood, behavior, feelings of optimism or pessimism, and how our actions and thoughts can also affect hormones.
• The previous episode discussed sexual development from chromosomes to puberty, while this one will concentrate on post-pubertal processes with an integration of practical optimization tips for hormones.

Salutogenesis: A Powerful Way to Conceptualize Health (00:07:00)

• The concept of salutogenesis is introduced as an approach emphasizing behaviors that promote well-being beyond the baseline, as opposed to the pathogenic model which focusses on avoiding diseases.
• Salutogenesis involves a proactive mindset towards health-driven behaviors like exercise and proper nutrition—not solely for disease prevention but for enhancing quality of life.
• The mindset and understanding of salutogenic actions can amplify their physiological benefits, as evidenced by studies showing better health outcomes when individuals are cognizant of the positive impacts of their behavior.

Estrogen and Testosterone: Sources, Levels & Ratios (00:10:03)

• Estrogen and testosterone, along with their derivatives, are sex steroids present in everyone, with varying ratios influencing well-being, anxiety, reproduction, and sexual behavior.
• These hormones can be optimized through behaviors, dietary supplements, and medications.
• Estrogen and testosterone are majorly produced by ovaries and testes, respectively, but adrenals can also produce testosterone.
• Aromatases are enzymes that convert testosterone into estrogen and are made by body fat and the testes.
• There is a wide range of hormonal levels between individuals and within an individual's lifespan.
• Hormonal levels vary greatly; for example, estrogen increases during puberty in females and decreases after menopause, while testosterone fluctuates less predictably in males, sometimes remaining high even into advanced age.
• The release of steroid hormones like testosterone from the adrenals is activated by competition.

The Power of Competition, Plus: Anxiety, Persistence & Dopamine (00:15:46)

• Competition is closely linked to sex steroid hormones, which in turn affect competitive behavior.
• Testosterone reduces anxiety and promotes novelty-seeking and competitive interactions, while binding to the amygdala to change stress thresholds.
• Both males and females with high testosterone engage in more novelty-seeking behaviors and have heightened libidos.
• Competitive environments can raise testosterone levels, and winning can increase both dopamine and testosterone.
• Dopamine released in the brain stimulates the production of more testosterone.
• All individuals within a species are involved in competition for resources and mates.

Testosterone & Libido Pre-Ovulation (00:20:58)

• Testosterone increases in females lead to a rise in libido, especially pre-ovulation.
• This effect is consistent regardless of the individual's chromosomal or gonadal background.

Estrogen & Sexual Receptivity; Libido In Males (00:21:48)

• In females, estrogen increases promote receptivity to mating, while in males, both testosterone and estrogen are necessary for libido, with estrogen playing a crucial role.
• Balance between hormone levels is important for sexual function in both males and females; high testosterone does not guarantee high libido without sufficient estrogen.

How Sex Behavior Impacts Testosterone: Observing vs. Actual vs. Abstinence (00:23:10)

• Testosterone promotes sex-seeking behavior and can be increased by sex.
• During sex, testosterone increases significantly, especially if there's no ejaculation.
• Observing sexual activity, such as pornography, leads to modest testosterone increases.
• Actual sexual intercourse leads to a greater increase (approximately 70%) in testosterone.
• Abstinence or avoiding ejaculation can lead to an increase in testosterone levels by up to 400%.
• Ejaculation does not decrease testosterone but increases prolactin, influencing the refractory period.

Testosterone & Prolactin: Sex Seeking vs Pair Bonding (00:26:46)

• Testosterone and dopamine rise during sex-seeking and sexual activity.
• After sex, prolactin levels increase, which may facilitate pair bonding by promoting calmness and intimacy.

DHEA (dehydroepiandrosterone): Effects on Levels/Ratios (00:27:30)

• DHEA increases both testosterone and estrogen.
• The effect of DHEA on hormone levels depends on a person's starting hormone levels and aromatase activity.
• Aromatase activity can shift DHEA conversion towards estrogen rather than testosterone production.

Behaviors That Decrease Testosterone (& Cortisol): Parenting & Prolactin (00:28:45)

• Parenting, especially among expecting fathers, can lead to decreased testosterone, decreased cortisol, and increased estradiol.
• Increased prolactin due to parenthood influences these hormonal changes.
• Prolactin suppresses sex steroid hormones and promotes hormones associated with parenting behavior.

How Illness Impacts Testosterone & Estrogen: Cytokines, e.g., IL-6 (00:31:24)

• Illness, by increasing inflammatory cytokines such as IL-6, reduces the desire for sex and hormones like testosterone and estrogen.
• IL-6 inhibits the gonads and interferes with hormone receptors.
• Modulating IL-6 and increasing IL-10, an anti-inflammatory cytokine, can support sex steroid hormones.

How Exactly Do Behaviors Change Hormones? (00:33:20)

• Behaviors can significantly influence hormone levels, like testosterone and estradiol.
• The mechanisms through which behaviors impact hormones may include exposure to smells or potentially pheromones.

Pheromones: Miscarriage, Menstrual Cycles, Puberty Onset, & Mate Recognition (00:34:18)

• Pheromone effects are well-established in animals but controversial in humans.
• The Lee-Boot effect shows the impact of male presence on female ovulation cycles, but a human equivalent is not identified.
• The Bruce effect involves pregnant animals aborting when the father is replaced by a new male due to male pheromones activating certain hormonal systems.
• The Vandenbergh effect accelerates female puberty when exposed to a novel sexually competent male; mature females can delay puberty in juveniles.
• Pheromones modulate menstrual cycles in other females, as shown in studies like Stern and McClintock's experiment with sweat on pads, without necessarily causing synchronization.
• The role of the vomeronasal organ (VNO), which detects pheromones, is unclear in humans, with Jacobson's organ being a potential equivalent.
• A study demonstrated that women could identify their partner's t-shirt from many others, suggesting the presence of imperceptible pheromone cues.
• Pheromones might influence mate recognition and attachment, and perfume manufacturers exploit this concept.
• Animals exhibit the flehmen response to detect mating pheromones, reflecting a connection between smell and taste similar to what might occur in humans through perfumes containing pheromones.

Apnea: A Powerful Bi-Directional Influence On Estrogen & Testosterone (00:43:33)

• Apnea, involving under-breathing and CO2 buildup, is linked to poor estrogen and testosterone levels.
• Both advanced menopause symptoms and early-onset andropause are associated with apnea.
• Estrogen and testosterone may influence breathing patterns; their receptors are found in lung-innervating neurons.
• Directionality is unclear, but improving breathing, especially during sleep, can optimize hormones.
• Apnea primarily refers to cessation of breathing during sleep and can be mitigated with practices like the physiological sigh.

Mouth vs. Nose Breathing & Hormone Levels: Effects Via Sleep and Direct Effects (00:47:44)

• Nasal breathing is superior to mouth breathing for numerous health benefits.
• Benefits include improved facial cosmetic features, better gas exchange, and hormone optimization.
• Proper nasal breathing contributes to the effectiveness of deep sleep, supporting gonad function and thus hormone production.
• Reducing apnea through proper breathing enhances males’ testosterone and females’ estrogen to testosterone ratios.
• Hormone optimization from proper nasal breathing stems from enhanced sleep quality and reduced stress.

How Sleep Adjusts Cortisol/Testosterone and Cortisol/Estrogen Ratios (00:51:11)

• Adequate sleep can modulate cortisol, thereby affecting testosterone and estrogen levels.
• Cholesterol can convert to either testosterone or estrogen, but high cortisol diverts it towards cortisol production, lowering sex hormones.
• Nasal breathing during the day and in sleep is crucial for reducing apnea and regulating cortisol, testosterone, and estrogen.
• For severe sleep apnea, a CPAP machine may be needed, while others might benefit from mouth taping during sleep.
• During the day, nasal breathing can be improved by dilating nasal passages to encourage better breathing habits.

02:CO2 Ratios, Nasal Breathing During Exercise (00:53:49)

• Breathing through the nose, especially during cardiovascular exercise, improves over time as sinuses dilate.
• Nasal breathing has several benefits including reducing apnea, increasing lung capacity, reducing cortisol levels, and indirectly raising testosterone and estrogen.
• This practice is cost-free and positively affects hormonal balance, sleep quality, and cosmetic aspects.
• Exceptions to nasal breathing include swimming and certain sports where mouth-breathing is appropriate.

Light Viewing Patterns & Hormones: Dopamine, GnRH (00:56:30) & Spring Fever: Tyrosinase, Hair Color, Mating Frequency (00:57:44)

• Light viewing, especially within the first hour of waking, can significantly impact hormone levels and fertility.
• The relationship between light, dopamine, and hormones influences libido, healing, and overall well-being.
• Dopamine, which promotes sex steroid hormone release, is linked to color changes in seasonal breeding animals.
• Increased sunlight exposure to the eyes elevates mood in humans, correlating with higher levels of sex steroids and reproductive behaviors.
• A protocol for optimal hormone levels involves exposing the eyes to bright light (not through sunglasses) early in the day for 2-10 minutes and avoiding bright light at night.

Specificity of Hormone Effects (01:04:39)

• Proper breathing and light-viewing habits, supporting healthy sleep, can positively influence sex steroid hormone levels.
• Light viewing increases the right hormone ratios whether one has higher estrogen or testosterone.
• The practice ensures the optimization of hormone ratios according to a person's natural levels.

Temperature: Cold & Hot Gonads (01:06:03)

• Temperature, along with day length and sunlight, affects hormone levels, with testosterone and estrogen typically being lower in colder months.
• In sports and bodybuilding communities, cold exposure at the gonadal level is used to try and increase testosterone and libido.
• Studies suggest that the cold does not directly affect hormone levels; instead, cold exposure leads to a rebound in vasodilation, increasing blood flow into the gonads.
• The vascular system, controlled by neurons, plays a role in hormone delivery. Cold exposure may temporarily shut down these neurons controlling vasoconstriction.
• After cold exposure and subsequent rewarming, a rebound hyper-vasodilation possibly delivers higher levels of hormones to stimulate gonad activity.
• There is no clear evidence that cold and heat directly affect testosterone and estrogen production; they more likely modulate hormone levels through mechanisms like blood flow.
• Excessive heat can damage sperm health and fertility, potentially altering proteins crucial for sperm function, independent of its role in hormone production.

How To Exercise: Types, Effort Level, Sequencing (01:14:10)

• Weight training of heavy resistance, in the 1-8 rep range, significantly boosts testosterone for a day or up to 48 hours in males and females.
• Studies focused on neuroscience indicate neurological engagement during high-threshold motor unit recruitment for moving heavy loads, but not to failure, stimulates increased testosterone or receptor activity.
• High-intensity, weight training that does not reach muscle failure is scientifically backed to best increase testosterone.
• Specific exercises or movements have not been fully explored for their direct mechanisms on boosting testosterone.

Cardio/Endurance vs. Resistance Training (First or Last?) Yes, It Matters (01:21:42)

• Performing weight training first, followed by cardio or endurance workouts, in the same session is optimal for testosterone.
• On separate days, the sequence of cardio and weight training does not impact testosterone.
• High-intensity interval training boosts testosterone, whereas prolonged endurance activity beyond 75 minutes may lower it, likely due to cortisol increases.
• It is unclear if less intense activities like hiking for extended durations have the same testosterone-reducing effect as more intense endurance exercises.
• To manage cortisol, endurance exercises should ideally be kept under 75 minutes and not be too intense.
• Professional endurance athletes occasionally use exogenous testosterone to negate cortisol-induced reductions during prolonged exertion.

Estrogen & Menopause: Compounds That May Ameliorate/Reverse Symptoms (01:24:41)

• Menopause is characterized by a massive reduction in estrogen due to depleted ovary function.
• Common menopausal symptoms include hot flashes, mood swings, migraine headaches, and brain fog.
• Hormone therapy is used to supplement estrogen, with varying success and potential side effects.
• Concerns arise when supplementing estrogen with a family history of breast cancer, due to estrogen-dependent cancers.
• Non-estrogenic alternatives, such as black cohosh and Panax ginseng, show modest benefits in improving menopause symptoms.
• Pueraria mirifica has evidence suggesting it is comparable to estrogen therapy in reducing menopause symptoms.
• All hormone-related treatments should be approached with caution and discussed with a healthcare provider.

Nutrients That Optimize The Foundation For Hormones (01:33:18)

• Certain nutrients are key for promoting proper testosterone and estrogen production, including vitamin D, zinc, and magnesium.
• Deficiencies in these nutrients negatively impact the endocrine system, including sex-steroid hormone production.
• Dosage for nutrients should be individual-dependent and based on blood work results.
• Regular blood work can help monitor and adjust levels of androgens and other vital nutrients.

Opioids as Severe Hormone Disruptors (01:36:00)

• Opioids dramatically reduce levels of sex-steroid hormones in both men and women.
• Opioid usage disrupts receptors on gonadotropin-releasing hormone neurons in the hypothalamus, affecting the pituitary.
• Long-term or high-dosage opioid use leads to endocrine syndromes such as gynecomastia in men and ovary disruptions in women.
• The major effect of opioids on hormones is the suppression of GnRH production, which in turn lowers testosterone and estrogen release.

Testes, Antlers & Ovaries (01:37:23)

• Various substances claimed to affect androgens range from deer antler material to consumption of bull testes.
• The industry around testosterone is vast and has historical roots.
• Understanding of estrogen structure led to birth control pill development.
• Scientific support exists for some supplements that can adjust androgens like testosterone and DHT.

Creatine & Increasing DHT (Dihydrotestosterone) (01:38:50)

• Creatine is observed to increase DHT levels, influencing masculinization and potentially contributing to hair loss depending on individual susceptibility.
• The mechanism by which creatine affects DHT is unclear, but may involve increased 5-alpha reductase activity or enhanced susceptibility of testosterone to enzymatic reactions.

Free and Bound Testosterone: SHBG (Sex Hormone Binding Globulin), Tongat Ali (01:40:14)

• Testosterone in the blood exists in both free and bound forms, with most being bound to SHBG or albumin for transport.
• The role of binding globulins is transportational, not merely to reduce bioavailable testosterone.
• Supplements like tongkat ali are reported to promote fertility, increase free testosterone, and have subtle aphrodisiac effects.

Nettles, Prostate, Boron, & Blood Brain Barrier (01:43:23)

• Nettles may free up testosterone but could also affect the prostate and liver.
• Boron has some scientific support for increasing free testosterone.
• Albumin is important for allowing testosterone to reach the brain and influence behavior.

Hormone Related Cancers: Sometimes Reducing Estrogen and Testosterone Is Optimal (01:45:27)

• Modulating hormones can impact tissues that depend on those hormones, making tissues with rapid cell turnover, like breast and testicular tissue, susceptible to cancer.
• Anti-androgenic drugs are used to prevent testosterone from promoting tumor growth.
• An increase in androgens or estrogens is not universally beneficial; moderation is key, especially given the link to cancer in rapidly replicating tissues.

Ecdysteroids: Mimic Mammalian Hormones (01:47:43)

• Ecdysteroids like turkesterone from spinach have similarities with cholesterol, the precursor to testosterone, cortisol, and estrogen.
• Ecdysteroids are bioavailable, or their metabolites are, and can be effective in humans, having traditionally been thought limited to other species.
• A study suggests ecdysteroids significantly increase muscle mass and strength above placebos, prompting recommendations for their prohibition in sports.
• There is ongoing debate around hormone augmentation in sports, particularly testosterone following injuries, which legally enhances recovery and performance.
• Estrogens and testosterones modulate gene expression and the brain's response to effort and anxiety.
• Supplementation effects are generally more subtle compared to direct hormone injections.

Optimizing Brain Hormones: Chorionic Gonadotropin, Fadogia Agrestis (01:51:50)

• Hormones like luteinizing hormone (LH) from the pituitary promote the release of other hormones in the body; LH specifically aids in sperm/testosterone production and egg/estrogen production.
• Synthetic human chorionic gonadotropin (hCG) increases fertility in both genders by mimicking the effect of LH.
• hCG, at one time collected from the urine of pregnant women, is now synthetically available and used for fertility and sometimes athletic performance.
• The supplement Fadogia agrestis has been shown to increase LH, which in turn raises levels of testosterone and estrogen.
• The ratio of hormones can affect the increase for individuals with different chromosomal or gonadal backgrounds.
• The importance of blood work is emphasized for anyone considering hormone-modifying supplements due to potential negative feedback mechanisms.

Additional Compounds, Liver Toxicity, Overall Milieu (01:57:18)

• The list of compounds affecting estrogen and testosterone is extensive, but focus is on those with human studies.
• Bulbine natalensis increases testosterone in rat studies, but has concerns about liver toxicity and lacks robust human studies.
• Sponsored research may provide biased evidence for certain compounds compared to independent studies.
• Other supplements mentioned, such as magnesium, D3, and zinc, create a supportive milieu for normal hormone production rather than significantly increasing levels.
• Differentiating between supplements that offer general support and those that cause major hormonal changes is important for understanding individual effects.