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The Science of Healthy Hair, Hair Loss and How to Regrow Hair — Whalespan

Content›Video›The Science of Healthy Hair,…

The Science of Healthy Hair, Hair Loss and How to Regrow Hair

Andrew Huberman2h 5m · 2023-04-10

Claims Made

222

Claims Supported

141

Support Rate

64%

Support rate

141 of 222 claims supported

141 supported81 partial / not

Claims from this content

172

✓Well SupportedProbiotics in Athletic Greens are vital for microbiotic health, which communicates with the brain and immune system to impact immediate and long-term health.✓Well SupportedQuality sleep, regulated by core body temperature changes, is foundational for mental health, physical health, and performance.✓Well SupportedAg One (formerly Athletic Greens) is a vitamin, mineral, and probiotic drink that provides foundational nutritional needs.✓Well SupportedEven mild dehydration can impair cognitive and physical performance.Well Supported

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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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N. Park

2d

Would love a "what would change this verdict" RSS feed. Sign me up if it exists.

✓

Minoxidil decreases the number of follicles in the resting phase and keeps them in the growing phase, resulting in better, thicker, stronger, and healthier hair.

✓Well SupportedAndrew Huberman typically drinks an electrolyte supplement first thing in the morning and also during and after sauna use.

✓Well SupportedFadogia agrestis may be beneficial for individuals with low luteinizing hormone levels, provided there are no issues with prolactin or opioid receptor antagonism.

✓Well SupportedPost-finasteride syndrome symptoms can be permanent in some individuals after drug discontinuation.

✓Well SupportedLMNT electrolyte mix contains 1000mg sodium, 200mg potassium, and 60mg magnesium.

✓Well SupportedBlack pepper extract (bioperine) is a 5-alpha reductase inhibitor that can affect liver cytochrome and contribute to turmeric supplement side effects.

✓Well SupportedCombining microneedling and finasteride, augmented with ketoconazole shampoo and saw palmetto, is likely the most effective approach for hair regrowth.

✓Well SupportedTarget blood iron levels are 25-100 for women and 30-150 for men.

◐Partially SupportedPost-finasteride syndrome can cause severe side effects like reduced libido, erectile dysfunction, and depression.

✓Well SupportedPractices like dry needling, scalp massage, or other methods to improve blood flow to the scalp can be beneficial for hair growth.

✓Well SupportedIngesting or applying caffeine to the scalp can suppress PDE, increase IGF-1, and promote or maintain hair growth.

✓Well SupportedGlucose is not the only or preferred fuel for the brain; ketones may offer neuroprotective benefits.

✓Well SupportedFinasteride stops hair loss in 80-90% of men over two years and increases hair count by 10%.

✓Well SupportedImpairments in physical or cognitive performance under slight dehydration are explained by the body's need for fluid and water.

◐Partially SupportedPRP involves drawing blood, spinning it to separate components, and re-injecting the platelet-enriched plasma to encourage nutrient delivery.

◐Partially SupportedEffective dosages of finasteride for hair growth range from 0.01mg to 5mg per day.

✓Well SupportedStress can lead to excessive hair shedding and accelerate hair follicle miniaturization.

✓Well SupportedHair loss is an ongoing process from age 30 to 50, with noticeable thinning typically becoming apparent by age 50.

✓Well SupportedSide effects of finasteride can be mitigated by changing the dose, timing, frequency, or by switching from oral to topical application.

◐Partially SupportedThe duration of the anagen hair growth phase varies between different hair types.

◐Partially SupportedBerberine can cause headaches, dizziness, and hypoglycemia if taken on an empty stomach.

✓Well SupportedApplying 1 mL of topical minoxidil to the scalp at night or in the morning, with massage, is a recommended protocol.

◐Partially SupportedScalp hairs have a prolonged anagen phase, while eyebrow hairs have a shorter anagen phase.

◐Partially SupportedTopical finasteride can enter the systemic circulation and is more difficult to dose than oral finasteride.

◐Partially SupportedMicro-needling with needles from 0.5mm to 2.5mm can reactivate stem cells in hair follicles to promote hair growth.

✓Well SupportedMinoxidil increases blood flow to hair follicles through vasodilation, extending the anagen phase of hair growth.

◐Partially SupportedKetone IQ increases blood ketones, which can benefit cognitive function.

◐Partially SupportedCaffeine and Minoxidil are generally used as preventatives for hair loss and are not expected to create significant new hair growth.

◐Partially SupportedFor finasteride, start with a low dose for at least 25 weeks before considering an increase.

◐Partially SupportedDopamine is involved in reward and motivation and can create an upbeat mood when released appropriately.

✕Not SupportedFinasteride and dutasteride can cause sexual dysfunction that may be permanent even after discontinuing the medication.

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

◐Partially SupportedMinoxidil is effective at slowing hair loss in individuals beginning to experience hair loss.

✓Well SupportedBotox injections on the scalp can relieve tension, potentially increasing blood flow to hair follicles and stimulating hair growth.

◐Partially SupportedCombination treatments for hair growth are superior to monotherapy.

◐Partially SupportedKetoconazole shampoo for hair loss should have at least a 2% concentration for effectiveness.

◐Partially SupportedDutasteride potently inhibits all three 5α-Reductase enzyme isoforms at typical oral dosages of 0.5mg to 2.5mg.

✓Well SupportedThe psychological distress caused by hair loss should not be dismissed.

◐Partially SupportedHair follicles maintain stem cells throughout the lifespan that give rise to new hairs.

◐Partially SupportedReducing finasteride dosage can help mitigate side effects without negatively impacting hair growth.

◐Partially SupportedTreatments that increase blood flow to the scalp can slow hair loss or extend hair growth duration.

◐Partially SupportedFinasteride and dutasteride inhibit 5-alpha reductase and reduce DHT to promote hair growth.

◐Partially SupportedTopical finasteride is typically available as a 1% solution or ointment applied to the scalp.

◐Partially SupportedKetoconazole shampoo used 2-4 times per week with 3-5 minutes of scalp contact has an 80% response rate for maintaining hair.

◐Partially SupportedStem cells and melanocytes at the base of the hair bulb require significant blood flow, including oxygen delivery, to support active hair growth and pigmentation.

◐Partially SupportedAndrogens inhibit IGF-1 and cyclic AMP, pathways that extend the anagen phase of hair.

◐Partially SupportedFinasteride response and side effect profiles vary widely among individuals due to differences in isozyme production.

◐Partially SupportedPlatelet-rich plasma (PRP) is a concentrated portion of blood containing platelets, used for injection into joints, tendons, or other tissues to promote healing.

◐Partially SupportedLow-dose tadalafil (2.5-5mg) may be prescribed to increase blood flow to the scalp and maintain hair.

◐Partially SupportedPRP is not stem cells, and claims of stem cell injections should be scrutinized, especially if from outside the US, Canada, or Northern Europe.

◐Partially SupportedDosing regimens for oral minoxidil in alopecia vary from 0.25 to 5 mg daily, depending on whether the alopecia is scarring or non-scarring.

✓Well SupportedDihydrotestosterone (DHT) binds to the androgen receptor with five times the affinity of testosterone.

◐Partially SupportedPhysicians ideally start Minoxidil at low dosages and gradually increase to find the minimal effective dose.

◐Partially SupportedA reasonable recommendation for finasteride use is 0.5mg to 1mg daily oral, or 1ml of 0.25% topical applied once per week.

✕Not SupportedSide effects of Minoxidil in women are similar to those in men, including swelling, headaches, and dizziness.

◐Partially SupportedThe combination of microneedling and Minoxidil is more effective for hair growth than either treatment alone.

◐Partially SupportedSaw palmetto weakly inhibits 5-alpha reductase, thereby reducing DHT, and has few side effects.

◐Partially SupportedApplying 1ml of 0.25% topical finasteride to the scalp results in blood concentrations equivalent to 2.5mg of oral finasteride.

◐Partially SupportedDutasteride at 0.5mg can reduce DHT levels by 95%.

◐Partially SupportedHigher density of DHT receptors in specific scalp locations may contribute to hair loss in those areas.

◐Partially SupportedSermorelin increases growth hormone secretion and IGF-1 levels.

◐Partially SupportedInhibiting 5-alpha reductase reduces DHT, which can maintain hair growth phase and prevent follicle miniaturization.

◐Partially SupportedScalp hairs can re-enter the anagen phase and regrow with sufficient stem cells, oxygen, blood support, hormonal signals, and reduced telogen triggers.

◐Partially SupportedEyebrow hairs grow at an average rate of about 4.2mm per month.

◐Partially SupportedSermorelin can be used to indirectly increase IGF-1 and promote hair growth.

◐Partially SupportedIncreasing IGF-1 can promote hair growth and maintenance.

◐Partially SupportedA daily dose of approximately 300mg of saw palmetto, divided into two or three doses, may help retain or grow hair.

✕Not SupportedHigh dosages of curcumin (1-2 grams) can cause severe adverse effects, including feeling dreadful.

◐Partially SupportedRegular cardiovascular exercise, resistance exercise, and maintaining a healthy body fat percentage improve insulin sensitivity and avoid hair loss.

◐Partially SupportedPrescription growth hormone and IGF-1 treatments can increase height in children, bone mass and density, fat loss, leanness, hair growth, and skin turnover.

✕Not SupportedElevated prolactin due to Minoxidil can cause reduced libido, decreased well-being, apathy, gynecomastia, and milk letdown.

◐Partially SupportedIron levels should be measured, as both too little and too much iron can be toxic.

◐Partially SupportedGrowth hormone is released from the anterior pituitary during the first hours of sleep, particularly with regular bedtimes and when fasting for two hours prior to sleep.

◐Partially SupportedHair grows from the root deep within the scalp, not from the surface.

◐Partially SupportedSufficient biotin is important for hair, and extra biotin from shampoo might contribute.

◐Partially SupportedIrregular bedtimes, especially going to sleep much later than usual, can cause individuals to miss the natural growth hormone pulse that occurs in the first 2-3 hours of sleep.

✕Not SupportedOral caffeine intake is unlikely to be effective for hair loss due to systemic absorption.

◐Partially SupportedDetermining the correct Minoxidil dosage often involves identifying unwanted side effects like dizziness, ankle swelling, edema, or hyperprolactinemia.

◐Partially SupportedStem cells can differentiate into other cell types and replicate, and in adults can be associated with cancer.

◐Partially SupportedSaw palmetto and ketoconazole shampoo are weak DHT antagonists, with ketoconazole also stimulating hair growth through other pathways.

◐Partially SupportedDutasteride works 2-5 times faster than finasteride for hair regrowth.

◐Partially SupportedHormones like estrogen, thyroid hormone, insulin-like growth factor, and androgens regulate hair growth by controlling the size of hair stem cell pools.

✕Not SupportedThere is insufficient clinical data to recommend PRP as a treatment currently, especially given its high cost.

◐Partially SupportedA systemic concentration of 0.2mg of finasteride is effective for stimulating new hair growth and maintaining existing hair.

◐Partially SupportedIndividual responses and side effect profiles to hair growth treatments vary enormously and cannot be predicted a priori.

◐Partially SupportedBotulinum neurotoxin (Botox) works by cleaving a protein in neurons, preventing the release of chemicals that activate other neurons.

◐Partially SupportedCutis verticis gyrata is almost always associated with pattern hair loss.

◐Partially SupportedThe catagen phase of the hair cycle involves the hair receding from the bulb region upwards towards the skin surface.

◐Partially SupportedBotox injections for scalp tension are temporary and require repeated treatments.

◐Partially SupportedSome individuals are highly sensitive to finasteride, experiencing rapid and dramatic side effects.

◐Partially SupportedIncreased 5-alpha reductase activity with age converts more testosterone to DHT, which inhibits hair growth by reducing IGF-1 and cyclic AMP, leading to pattern hair loss in about 50% of people by age 50.

◐Partially SupportedHairs are composed of stacked keratin proteins bound together, providing tensile strength.

◐Partially SupportedMany stem cell populations, such as those for new brain cells, disappear after puberty.

◐Partially SupportedHead hairs can continue to grow for 4-8 years without being cut.

◐Partially SupportedTopical Minoxidil is typically a 5% solution used once or twice daily.

◐Partially SupportedMinoxidil treatment for hair loss is likely a lifelong commitment.

◐Partially SupportedSebum produced by sebaceous glands waterproofs skin and provides antibacterial properties.

◐Partially SupportedSaw palmetto, topical caffeine, and ketoconazole are preferable to potent systemic inhibitors for mild inhibition of the DHT pathway to maintain or grow hair.

✕Not SupportedMicroneedling alone is not effective for recovering bald scalp regions with no stem cell population.

✕Not SupportedGrowth hormone and IGF-1 treatments carry risks, including increased cancer risk.

◐Partially SupportedSide effects from ketoconazole occur in 1-8% of users and are typically mild, such as scalp irritation or hair thinning/brittleness.

◐Partially SupportedBotox injections to flatten scalp folds in cutis verticis gyrata can reduce folds and improve hair growth.

◐Partially SupportedManipulations like not wearing hats or massaging the scalp alone are not sufficient to robustly enhance hair growth rate.

◐Partially SupportedLow levels of inflammation caused by procedures like micro-needling or PRP injections can reactivate waning stem cell populations and re-enter follicles into the cell cycle.

◐Partially SupportedStem cells are present from the beginning of life and are responsible for cell replication and development.

◐Partially SupportedPRP injections are used into ovaries to support follicle and egg health for conception, and into joints for joint health.

◐Partially SupportedPRP is used to offset or reverse hair loss by increasing blood flow to the hair stem cell niche.

◐Partially SupportedCyclic AMP stimulates hair follicle growth.

✕Not SupportedThe myth that balding patterns are inherited from one's mother's father is false.

◐Partially SupportedDihydrotestosterone (DHT) likely plays a role in the maturation of the hypothalamus and brain-genital axis in males into their 20s and 30s.

◐Partially SupportedMicro-needling and platelet-rich plasma share the critical element of needle injection into the skin.

◐Partially SupportedMicro-needling, PRP injections, and Minoxidil treatments aim to stimulate stem cell proliferation by increasing blood flow, oxygen, nutrient delivery, or localized inflammation.

◐Partially SupportedThe benefits of PRP injections may be due to factors other than the platelets themselves, such as mechanical stimulation or inflammation.

◐Partially SupportedPRP treatments for hair regrowth are expensive, often costing many thousands of dollars over multiple sessions, and their success tends to be transient.

◐Partially SupportedThe biology of hair growth and its inhibitors is discussed to help listeners evaluate treatments like lasers, PRP, finasteride, and dutasteride based on their mechanisms.

◐Partially SupportedPlatelet-rich plasma injections into the scalp have shown moderate success for hair regrowth.

◐Partially SupportedSufficient iron and ferritin levels are crucial for maintaining proper hair growth.

◐Partially SupportedMelanin is a protein injected into keratin that gives hair its darker color, and its absence results in white hair (albinism).

◐Partially SupportedDosing minoxidil can be complicated due to its potential to significantly lower blood pressure or lower it only slightly, depending on individual sensitivity.

◐Partially SupportedMinoxidil may not be sufficient for rapid hair loss as it only moderately extends the anagen phase.

◐Partially SupportedIncreasing finasteride dosage due to perceived lack of hair growth results may increase side effects.

◐Partially SupportedThe sebaceous gland produces sebum, which helps waterproof the skin and seals the hair exit point.

◐Partially SupportedGenes influence predisposition to balding, but the pattern is not solely determined by the mother's father.

◐Partially SupportedInhibiting dihydrotestosterone can support the preservation and regrowth of hair.

◐Partially SupportedNeedle lengths of 1mm to 2.5mm for micro-needling appear to be more effective for hair growth than shorter lengths.

◐Partially SupportedBotox treatments for the scalp require skilled practitioners to avoid adverse cosmetic outcomes.

◐Partially SupportedSome stem cell populations, like those in the brain, decrease significantly after puberty, while others persist throughout life.

◐Partially SupportedAndrogen-related alopecia is a primary cause of hair loss in men and women, particularly as they age.

◐Partially SupportedKetone-IQ can enhance performance during resistance training and endurance workouts.

◐Partially SupportedInsulin resistance and obesity can lead to hair loss by reducing IGF-1 activity at the hair follicle and stem cell.

◐Partially SupportedMyo-inositol, taken at 900mg before sleep, can improve insulin sensitivity and may aid sleep.

◐Partially SupportedDutasteride reduces DHT levels by approximately 95%, potentially causing side effects like reduced sex drive, reduced overall drive, increased estrogen and prolactin, and gynecomastia.

✕Not SupportedTopical finasteride application can lead to systemic blood concentrations significantly higher than the effective oral dose, potentially increasing side effect risk.

✕Not SupportedFinasteride has potential side effects if not dosed properly or in certain populations due to variations in individual 5-alpha reductase isoenzyme production.

✕Not SupportedLayering too many DHT-inhibiting treatments can lead to excessively low DHT levels and associated side effects.

?Limited ResearchThe efficacy of Botox for offsetting hair loss is not yet well-established by large-scale clinical studies.

◐Partially SupportedSaw palmetto is low-cost and available over-the-counter for hair loss, with a logical mechanism of action.

◐Partially SupportedMicro-needling shows positive benefits for hair growth, especially when combined with other treatments.

◐Partially SupportedDihydrotestosterone (DHT) shortens or halts the anagen phase of hair growth and extends the catagen and telogen phases, contributing to hair loss.

◐Partially SupportedKetoconazole, an antifungal, has been shown to increase hair number and diameter.

◐Partially SupportedReducing hypertension by expanding blood vessels can help maintain existing hair by increasing blood flow to the scalp.

◐Partially SupportedHair loss or changes in hair color can lead to intense anxiety or depression.

◐Partially SupportedWhen exploring hair growth treatments, start with minimal effective dosages and coordinate with a medical professional.

◐Partially SupportedAndrogen receptors on the face are responsible for beard growth, and higher DHT levels with age can lead to a thicker beard.

◐Partially SupportedKetoconazole likely works by offsetting reductions in the anagen phase and exacerbations of the telogen phase of hair growth, not by stimulating IGF-1 or activating growth directly.

◐Partially SupportedMinoxidil use can increase prolactin, which is antagonistic to dopamine.

◐Partially SupportedMinoxidil treatment for hair growth typically requires lifelong adherence to maintain results.

◐Partially SupportedDuring the telogen phase, no new hair proteins are produced, the hair follicle bulb pinches off and recedes, and the stem cell population and melanocytes may die, preventing future hair regrowth from that follicle unless specific conditions are met.

◐Partially SupportedThe rate of hair growth is generally consistent within a given body region, and perceived differences are likely due to variations in the duration of the anagen phase.

◐Partially SupportedFinasteride reduces DHT by inhibiting the type two isoenzyme of 5-alpha reductase, leading to a potential increase in hair count by up to 20%.

◐Partially SupportedHormones like DHT have impacts across the lifespan.

◐Partially SupportedPDE and TGF-beta-2 act as brakes on hair growth.

◐Partially SupportedHealthy women have higher levels of testosterone than estrogen, although typically lower absolute levels of testosterone than men.

◐Partially SupportedDHT is associated with desirable traits including mental vigor, physical vigor, strength, healing capacity, drive, and libido.

◐Partially SupportedThe 'micro' aspect of micro-needling is crucial, as significant damage, like scarring, prevents hair growth from those areas.

◐Partially SupportedLow-dose Tadalafil may be a better alternative than Minoxidil for increasing scalp blood flow due to fewer side effects.

◐Partially SupportedDihydrotestosterone (DHT) is converted from testosterone by the enzyme 5-alpha reductase in both men and women.

◐Partially SupportedOral Minoxidil dosage should start at 0.25mg and increase as needed to avoid side effects.

◐Partially SupportedPost-finasteride syndrome appears to occur more frequently in younger males (20s and 30s) taking high doses for hair growth compared to older males taking finasteride for prostate issues.

◐Partially SupportedMinoxidil increases blood flow to the hair stem cell niche, supporting hair growth and maintenance.

◐Partially SupportedPsychological well-being can impact hair growth rates and coloration.

◐Partially SupportedTopical caffeine ointments for hair loss may be best applied about three times a week.

◐Partially SupportedCaffeine is being used as a treatment to regrow hair.

✕Not SupportedExcessive iron intake can be toxic, while insufficient iron can lead to anemia.

◐Partially SupportedFinasteride was originally developed to treat prostate enlargement by reducing DHT.

◐Partially SupportedBotulinum neurotoxin injected into muscles causes paralysis by blocking nerve-muscle communication.

◐Partially SupportedSide effects of finasteride increase with higher bloodstream concentrations.

◐Partially SupportedThe arrector pili muscle contracts when exposed to cold or fear, trapping air to help warm the body.