Andrew Huberman about hair

1) Huberman discusses the interesting biology and psychology surrounding hair, particularly hair loss and regrowth. While stress and anxiety can impact hair growth rate and coloration, they are not the most important factors in determining the health of your hair. He speaks to experts regarding the stem cells that give rise to hair growth and pigmentation, as well as how to halt and even reverse hair loss.

2) Andrew explains that hair loss can be a major cause of anxiety and depression for many people, with up to 85% of those experiencing hair loss going out to try and halt or reverse it. By age 50, approximately 50%of all men and women will have experienced significant hair loss that is noticeable to them. Hair loss is an ongoing process that typically happens between ages 30 and 50. In thepodcast, the biology of hair growth is discussed, including the role of stem cells which are endogenous cells that give rise to other cells in the process of hair growth. Hormones, such as estrogen and androgens, play a role in hair growth and loss, and mechanical and chemical treatments for hair loss are explored.

3) Andrew explains the anatomy of hair and how stem cells play an important role in hair growth. At the base of each hair, there is a little cave or pocket containing stem cells that have the ability to divide and give rise to other cells. Those daughter cells then become the various types of cells that make up the hair, including the protein keratin. There are also cells that give rise to the pigment of the hair that creates melanin. Additionally, sebum, an oily secretion produced by sebaceous glands near the hair roots, plays an essential role in hair growth. Understanding these components could help reverse hair loss and reverse graying hair.

4) Andrew discusses the components of the region around hairs that are relevant to understanding how to replace hair that’s lost. Firstly, the sebum surrounding the hair provides two important functions. Firstly, it forms a seal that waterproofs the skin and secondly, ithas strong antibacterial and anti-microbial effects that prevent infection. Secondly, the erector pili muscle, which is a muscle between the bulb of the hair and the skin, contracts in response to cold or fear. This causes the hairs to stand up, trapping air to keep the body warm, and this is why people get goosebumps. Furthermore, the capillaries that deliver nutrients, oxygen,and blood flow to the hair bulb are essential for hair growth and stem cell and melanocyte populations that support the hairs. Increasing blood flow to these populations is essential for hair growth, and increasing the supply of oxygen is necessary to keep the process going.

5) No single manipulation has been found to significantly enhance hair growth on its own. A hair's growth process includes three primary phases: the anagen phase, where stem cells produce the hair's protein and hair growth occurs from the base of the hair; the catagen phase, where hair stops growing but is still present on the scalp; and the telogen phase, where the hair falls out and stays dormant until a new hair follicle replaces it. Different hairs on the body have varying durations of growth -phases, and blood flow to the scalp is crucial for the melanocytes, sebaceous gland, and erector pili muscle to function correctly.

6) Andrew discusses the life cycle of hair growth, which includes three critical stages: the antigen phase for hair growth, the catagen phase for the hair's receding and dying, and the telogen phase as a period of rest. While many people focus on the rate of hair growth, the duration of the antigen phase and catagen phase can vary between individuals and body regions, influencing the overall life cycle of hair growth. Additionally, stem cells and hormones play important roles in the hair growth process, with dihydrotestosterone causing changes in the bulb region and inhibiting hair growth.

7) Andrew discusses how hormones act as accelerators and brakes on the hair growth phases. For example, dihydro testosterone halts the antigen phase and promotes the catagen and telogen phases, while estrogen promotes hair growth. The podcast then goes on to discuss minoxidil, a drug designed to treat hypertension, which acts as an accelerator by increasing blood flow and extending the antigen phase. While minoxidil is effective for slowing hair loss, dosing can be complicated due to its potential to lower blood pressure.

8) Andrew discusses treatments that focus on the need for hair stem cells to receive proper blood flow in order to grow and remain healthy. One such treatment is minoxidil, which increases blood flow to the scalp and can slow hair loss or maintain the hair that one already has. Another treatment that is gaining attention is low-dose tadalafil, typically used to increase blood flow to the prostate, but now becoming recognized as a way to increase blood flow to all regions of the body, including the scalp, to maintain hair. The use of platelet-rich plasma injections is also discussed as a treatment to offset hair loss or even reverse it.

9) Andrew explains that PRP injections are not stem cell injections, despite the increasing popularity of PRP injections intovarious tissues, including the scalp. PRP injections are legal in many countries and are made from enriched platelets of someone’s own blood, which stimulate nutrient delivery to a specific area of the body. Although PRP injections have moderate success and work due to other reasons outside of platelet enrichment, such as microneedling, which is a mechanical stimulation of the hair follicle using tiny needles. This procedure has been shown to reactivate semi-quiescent populations of stem cells that stimulate hair growth and is also an effective augment for some hormone-based hair regrowth treatments.

10) Andrew discusses the science behind microneedling for hair growth and how it can be used in conjunction with other treatments like minoxidil or caffeine to stimulate stem cell proliferation and improve hair growth in both men and women of all ages. They emphasize the importance of the micro damage caused by microneedling, with needle lengths of 1-2.5mm being more effective than shorter lengths, and caution about potential bleeding and inflammation. The combination of microneedling and minoxidil is particularly effective in recovering dead zones, regions with no stem cell population, and can lead to new hair growth, although it may take up to 50 weeks. However, minoxidil treatment must be maintained for long-term hair growth.

11) The use of Botox to reduce the bumps on the scalp caused by cutus verticus gyrata, a syndrome associated with pattern hair loss, is discussed. Injecting Botox can allow the folds to sit flatter, leading to less bumps and improvements in hair growth in those areas. Chemical variables that control the duration of hair growth phases are also explored,with insulin growth factor one (IGF-1) and cyclic AMP identified as accelerators of hair growth by extending the antigen or growth phase. On the other hand, phosphodiesterase (PDE) and TGF beta 2 are identified as brakes on hair growth by either shortening the antigen phase or extending the catagen or quiescent phase. Androgen-related alopecia, which is induced by testosterone and its derivatives, is identified as the reason for hair loss in men and women.

12) Andrew discusses the role of testosterone, dihydrotestosterone, and androgen receptors in hair growth and hair loss. Testosterone levels are higher in younger males and females compared to older individuals, and DHT is responsible for hair loss by inhibiting hair growth through the reduction of igf-1 and cyclic amp. The pattern of hair loss differs depending on the pattern of androgen receptors on the scalp, which is inherited from one's mother's side. He also mentions that higher density of androgen receptors on the face results in thicker beard growth.

13) Huberman discusses the effects of Androgen receptors and their relationship to hair loss or growth. A high density of Androgen receptors on the back or face can lead to hair growth, but Androgen-dependent alopecia can occur on the scalp in regions with a high number of these receptors. While treatments to halt hair loss center around inhibiting DHT or five Alpha reductase, chemically adjusting substances in the hair growth pathway, such as caffeine, could stimulate hair growth or prevent hair loss. Caffeine is a potent pde inhibitor, and by indirectly stimulating igf-1, applying topical caffeine ointment or cream to the scalp could increase hair growth without the side effects associated with minoxidil.

14) Andrew discusses the use of caffeine to offset the death of the stem cell niche in the hair's telogen phase, potentially maintaining the stem cell population, making caffeine a beneficial choice in conjunction with various targeted DHT pathway chemical treatments. He further explores using prescription drugs such as growth hormone and sermorelin to increase hair growth by stimulating natural igf-1 production since insulin-like growth factor-1 is insulin-dependent. Insulin resistance can lead to hair loss, so avoiding insulin resistance is crucial when seeking to stimulate the natural production of igf-1. Over-the-counter supplements such as myoinositol, berberine, and metformin can assist in improving insulin sensitivity, and every supplement has its unique profile of effects.

15) Andrew discusses some herbal compounds and plant-based compounds that are believed by some to increase hair growth, such as Sal Palmetto Berry, Tonga Ali, fedojia agrestis, and curcumin. Herbal compounds and cocktails probably have some marginal effect on maintaining hair growth, but there are no clinical studies to support any one of them. He mentions that Sal Palmetto Berry inhibits 5-alpha reductase and DHT, and it is available over-the-counter and has a low incidence of side effects. He also discusses Nizoral or Ketoconazole, ananti-fungal that was initially developed to treat dandruff and severe psoriasis, which has been shown to be effective in increasing hair number and diameter. However, it can cause drying, thinning, and brittle hair.

16) Andrew discusses the effectiveness of ketoconazole shampoo in hair loss prevention and hair regrowth by reducing DHT's negative impact on the hair follicle. It has been shown that using this shampoo two to four times per week, with contact time of three to five minutes, can maintain 80% of hair that would otherwise be lost. However, it's unclear whether ketoconazole shampoo stimulates new hair growth, especially in areas where hair is thinning. The recommendation is to use a shampoo that's at least 2% concentration of ketoconazole, which may cause occasional side effects such as scalp irritation, thinning, and brittleness of the hair. Finasteride is another option for reducing DHT and preventing hair loss, which can increase hair count by up to 20%. It's been shown to reduce hair loss in 90% of users when taken properly.

17) Andrew discusses the use of finasteride for hairloss and the difference between oral and topical solutions. The effective dose of finasteride in the bloodstream is 0.2 milligrams, but one milliliter of topical finasteride at 0.25% leads to a 2.5 milligram concentration in the blood. This is important because the side effects of finasteride increase as the concentration increases. Therefore, it's essential to start with a low dosage of 0.5 milligrams to one milligram of finasteride as a tablet per day and slowly increase over time to find a safe and effective dose. He also explains the possible side effects of finasteride and the need to wait for several months before determining if a person needs to increase or decrease their dosage.

18) Andrew discusses the dosing regimens for finasteride, a medication used to treat hair loss in males, and potential risks associated with its use. He recommends starting with 0.5 milligrams to one milligram per day of oral finasteride, or one milliliter of 0.25 percent topical finasteride applied once a week. However, he warns of a new phenomenon called post-finasteride syndrome, which can occur in males who take the medication to offset hair loss and then stop. Symptoms include reduced libido, erectile dysfunction, and depression, and it is still unclear exactly what is causing it. The syndrome seems to occur more frequently in younger males who take higher dosages of finasteride, indicating that dihydrotestosterone may have further effects on male maturation beyond its known early roles in embryonic development and puberty.