- Reaction score
- 3,025
Estrogen is known to have complex effects on hair. It can both promote and inhibit hair growth depending on the type of estrogen used.
The primary factor that seems to determine the outcome of estrogen on your hair is which type of estrogen receptor you are stimulating with that type of estrogen.
Types of Estrogen Receptors
The body has two types of estrogen receptors. These two estrogen receptors have dramatically different effects on hair growth.
1) ER-alpha
ER-alpha is the type of estrogen receptor you DON'T want to stimulate.
With hair, ER-alpha stimulation promotes catagen. Catagen is the cessation of hair growth. ie. The end of anagen (growth phase). After catagen comes telogen (hair shed). Any estrogen which stimulates ER-alpha predominantly will therefore stall hair growth and lead to hair shedding. (ref)
ER-alpha stimulation also may lead to osteoarthritis and osteoporosis. (ref)
2) ER-beta
ER-beta by contrast is the estrogen receptor you DO want to stimulate.
ER-beta signalling works by silencing the ER-alpha catagen signalling pathway. By blocking this catagen signalling, hair follicles can grow longer and spend more time in anagen. This leads to longer and healthier hair. (ref)
Types of Estrogen
To evaluate the usefulness of any type of estrogen, we therefore need to know to what extent they stimulate ER-alpha vs. ER-beta receptors.
1) 17 beta-Estradiol (E2)
The primary estrogen of the natural human body is 17 beta-estradiol. Estradiol binds equally well to ER-alpha and ER-beta. (ref)
Estradiol binds most strongly to the estrogen receptors of the natural estrogens. (ref) We can therefore use estradiol as a standard to compare other estrogen binding strengths, and rate estradiol as "100" binding strength for both receptors.
Because estradiol binds equally to ER-alpha and ER-beta, I would postulate that overall this may likely be considered a "good" estrogenic agent for promoting hair growth, but not the best as we will soon see.
2) Estrone (E1)
Estrone is the primary estrogen of menopause. It has been described as the "ugly estrogen". (ref)
Estrone has a binding affinity for ER-α of 60 and for ER-ß of 37 (relative to estradiol). (ref) This means it is primarily an ER-alpha stimulator, and thus can be considered absolutely undesirable for hair growth.
Estrone will lead to premature catagen of hair follicles. It is likely the reason postmenopausal women lose hair all over their heads and bodies.
3) Estriol (E3)
Estriol binds to ER-α with an affinity of 14 and to ER-ß with an affinity of 21. (ref)
This means it is the only natural estrogen with a greater ER-beta affinity than ER-alpha.
Estriol is therefore the primary estrogen we DO want to use for hair growth.
Estriol is most famous for shooting up dramatically after about 12 weeks pregnancy (ref), and it is credited in part for the fantastic glowing skin and long thick hair that pregnant women experience from this point of pregnancy onward.
Estriol has a half life of 6-9 hours with vaginal application, which may be similar to skin application. (ref) Twice a day application thus makes the most sense. It has a low affinity relative to the other estrogens (it is the weakest to bind), so larger amounts must be used if its effects are desired.
4) Ethinyl Estradiol (EE)
This is the primary estrogen used in birth control pills. Unfortunately, EE is a mostly ER-alpha stimulator. (ref) This likely makes it less useful for hair growth promotion (unless you are using it orally for chemical castration, which will help stop male pattern hair loss by shutting down all your androgen production).
Normal women can likely get away with EE usage in birth control pills because even on high dose contraception, they will still have their natural estrogens (E1, E2, E3) to provide ER-beta stimulation and help counteract EE's ER-alpha effect. (ref, ref)
However, EE will not provide benefits for hair in this context, and should likely be minimized or avoided compared to other estrogens if hair growth is the desired outcome.
Manipulating Estrogen Receptor Expression
As @Georgie pointed out in another thread, dexamethasone (a steroid) has been shown to decrease ER-alpha receptor expression by up to 38%, while having no effect on ER-beta receptor expression. (ref)
This means that topical steroids could in theory be used to downregulate ER-alpha receptors in the scalp and promote a more ER-beta predominant effect.
Dexamethasone is used in combination with 17 alpha-estradiol (alfatradiol) in a German product called Ell-Cranell Dexa. I am unsure of the ER-alpha vs. ER-beta stimulating balance of 17 alpha-estradiol, but presuming it is similar to 17 beta-estradiol, the mechanism of action for this product would make sense. The steroid will shift receptor balance towards ER-beta predominance, and estradiol will then bind to these increased ER-beta receptors, stimulating hair growth.
The problem with this approach is that topical steroids can lead to skin atrophy over time, so they are not a good long term treatment. Additionally, the same predominantly ER-beta stimulation can be accomplished much more simply by just using estriol cream instead.
So although it is interesting to conceptualize, I do not think the alfatradiol/dexamethasone combo is the most useful approach to manipulating estrogen pathways for hair growth.
Summary
In other words:
For both men and women, the most useful approach to estrogen therapy in the pursuit of hair growth will therefore likely be a topical estriol cream applied directly to the areas of the hairline where stimulation is desired.
Fortunately, estriol creams are freely available most places over the counter. I have been using this one myself:
https://www.amazon.com/Bioidentical-Supplements-Micronized-Bio-Identical-Menopause/dp/B004XJIDEO
I have read a higher concentration of 0.3% estriol can be used in compounded creams for acne. This can also have an anti-aging effect. If you are brave, you can use it on your face as well for these benefits. (ref)
Primary risks of estrogen therapy in general for men will likely be sexual dysfunction. I have noticed some mild erectile dysfunction when I am using large amounts of estriol cream, but it doesn't bother me at this stage. Other risks for all estrogens are of blood clots, increased risk of breast cancer, etc. (ref)
For my own part, I will continue to use estriol for both hair growth promotion and anti-aging effect on my skin as I have been using it for about two months now and it has appeared to be quite effective for both. Dosage can easily be adjusted by using more or less cream to minimize side effects.
No treatment for hair loss or skin care is perfect or well suited for everyone. Most men will probably want to avoid estrogen therapies even just in principle alone. However, if used correctly, estrogen is likely a powerful hair growth tool to consider for those who wish to utilize it to their benefit.
The primary factor that seems to determine the outcome of estrogen on your hair is which type of estrogen receptor you are stimulating with that type of estrogen.
Types of Estrogen Receptors
The body has two types of estrogen receptors. These two estrogen receptors have dramatically different effects on hair growth.
1) ER-alpha
ER-alpha is the type of estrogen receptor you DON'T want to stimulate.
With hair, ER-alpha stimulation promotes catagen. Catagen is the cessation of hair growth. ie. The end of anagen (growth phase). After catagen comes telogen (hair shed). Any estrogen which stimulates ER-alpha predominantly will therefore stall hair growth and lead to hair shedding. (ref)
ER-alpha stimulation also may lead to osteoarthritis and osteoporosis. (ref)
2) ER-beta
ER-beta by contrast is the estrogen receptor you DO want to stimulate.
ER-beta signalling works by silencing the ER-alpha catagen signalling pathway. By blocking this catagen signalling, hair follicles can grow longer and spend more time in anagen. This leads to longer and healthier hair. (ref)
Types of Estrogen
To evaluate the usefulness of any type of estrogen, we therefore need to know to what extent they stimulate ER-alpha vs. ER-beta receptors.
1) 17 beta-Estradiol (E2)
The primary estrogen of the natural human body is 17 beta-estradiol. Estradiol binds equally well to ER-alpha and ER-beta. (ref)
Estradiol binds most strongly to the estrogen receptors of the natural estrogens. (ref) We can therefore use estradiol as a standard to compare other estrogen binding strengths, and rate estradiol as "100" binding strength for both receptors.
Because estradiol binds equally to ER-alpha and ER-beta, I would postulate that overall this may likely be considered a "good" estrogenic agent for promoting hair growth, but not the best as we will soon see.
2) Estrone (E1)
Estrone is the primary estrogen of menopause. It has been described as the "ugly estrogen". (ref)
Estrone has a binding affinity for ER-α of 60 and for ER-ß of 37 (relative to estradiol). (ref) This means it is primarily an ER-alpha stimulator, and thus can be considered absolutely undesirable for hair growth.
Estrone will lead to premature catagen of hair follicles. It is likely the reason postmenopausal women lose hair all over their heads and bodies.
3) Estriol (E3)
Estriol binds to ER-α with an affinity of 14 and to ER-ß with an affinity of 21. (ref)
This means it is the only natural estrogen with a greater ER-beta affinity than ER-alpha.
Estriol is therefore the primary estrogen we DO want to use for hair growth.
Estriol is most famous for shooting up dramatically after about 12 weeks pregnancy (ref), and it is credited in part for the fantastic glowing skin and long thick hair that pregnant women experience from this point of pregnancy onward.
Estriol has a half life of 6-9 hours with vaginal application, which may be similar to skin application. (ref) Twice a day application thus makes the most sense. It has a low affinity relative to the other estrogens (it is the weakest to bind), so larger amounts must be used if its effects are desired.
4) Ethinyl Estradiol (EE)
This is the primary estrogen used in birth control pills. Unfortunately, EE is a mostly ER-alpha stimulator. (ref) This likely makes it less useful for hair growth promotion (unless you are using it orally for chemical castration, which will help stop male pattern hair loss by shutting down all your androgen production).
Normal women can likely get away with EE usage in birth control pills because even on high dose contraception, they will still have their natural estrogens (E1, E2, E3) to provide ER-beta stimulation and help counteract EE's ER-alpha effect. (ref, ref)
However, EE will not provide benefits for hair in this context, and should likely be minimized or avoided compared to other estrogens if hair growth is the desired outcome.
Manipulating Estrogen Receptor Expression
As @Georgie pointed out in another thread, dexamethasone (a steroid) has been shown to decrease ER-alpha receptor expression by up to 38%, while having no effect on ER-beta receptor expression. (ref)
This means that topical steroids could in theory be used to downregulate ER-alpha receptors in the scalp and promote a more ER-beta predominant effect.
Dexamethasone is used in combination with 17 alpha-estradiol (alfatradiol) in a German product called Ell-Cranell Dexa. I am unsure of the ER-alpha vs. ER-beta stimulating balance of 17 alpha-estradiol, but presuming it is similar to 17 beta-estradiol, the mechanism of action for this product would make sense. The steroid will shift receptor balance towards ER-beta predominance, and estradiol will then bind to these increased ER-beta receptors, stimulating hair growth.
The problem with this approach is that topical steroids can lead to skin atrophy over time, so they are not a good long term treatment. Additionally, the same predominantly ER-beta stimulation can be accomplished much more simply by just using estriol cream instead.
So although it is interesting to conceptualize, I do not think the alfatradiol/dexamethasone combo is the most useful approach to manipulating estrogen pathways for hair growth.
Summary
In other words:
- ER-alpha signalling stimulates catagen (stopping hair growth dead)
- ER-beta signalling blocks the ER-alpha pathway (prolonging anagen and causing hair growth)
- Estradiol has a 1:1 alpha:beta binding ratio, estriol has a 3:2 beta:alpha binding ratio, and estrone has a 1.6:1 alpha:beta binding ratio (ref)
- Ethinyl estradiol has "ERα selective agonistic potency" (ref)
- Estriol (best) - 3:2 beta:alpha
- Estradiol (2nd best) - 1:1 beta:alpha
- Estrone (poor) - 1.6:1 alpha:beta
- Ethinyl estradiol (poor) - primarily alpha binding
For both men and women, the most useful approach to estrogen therapy in the pursuit of hair growth will therefore likely be a topical estriol cream applied directly to the areas of the hairline where stimulation is desired.
Fortunately, estriol creams are freely available most places over the counter. I have been using this one myself:
https://www.amazon.com/Bioidentical-Supplements-Micronized-Bio-Identical-Menopause/dp/B004XJIDEO
I have read a higher concentration of 0.3% estriol can be used in compounded creams for acne. This can also have an anti-aging effect. If you are brave, you can use it on your face as well for these benefits. (ref)
Primary risks of estrogen therapy in general for men will likely be sexual dysfunction. I have noticed some mild erectile dysfunction when I am using large amounts of estriol cream, but it doesn't bother me at this stage. Other risks for all estrogens are of blood clots, increased risk of breast cancer, etc. (ref)
For my own part, I will continue to use estriol for both hair growth promotion and anti-aging effect on my skin as I have been using it for about two months now and it has appeared to be quite effective for both. Dosage can easily be adjusted by using more or less cream to minimize side effects.
No treatment for hair loss or skin care is perfect or well suited for everyone. Most men will probably want to avoid estrogen therapies even just in principle alone. However, if used correctly, estrogen is likely a powerful hair growth tool to consider for those who wish to utilize it to their benefit.
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