Note: this article pertains to male-pattern baldness only.
THE SCIENCE AND TREATMENT
Male pattern baldness eventually becomes the bane of every man. Some begin to lose their hair as early as their late teens/early 20s, whereas others manage to keep their hair until very late in life. While there are a million myths out there related to the origins of male-pattern baldness, it all comes down to genetics and lifestyle.
The most difficult aspect of a man losing his hair is vanity. While no man wants to admit that he is even remotely vain, we all are to some degree. As men experience hair loss, they refuse to do anything about it for the sake of vanity. The irony is, however, the more hair a man loses, the more insecure and vainer he becomes (in most cases).
LET'S GET INTO THE SCIENCE
Male-pattern baldness is a result of a byproduct of testosterone, dihydrotestosterone ("DHT"), an androgen (i.e. hormone) that triggers the development of male characteristics during puberty. Ironically, DHT is critical for pubic hair development in men but is also responsible for men losing their hair on their head.
Hair follicle growth is broken into the following phases:
Anagen: this is the growth phase, and hairs in this phase remain for 2-6 years. The longer the phase, the longer the hair grows. About 85% of hairs on the head are in this phase at any given moment.
Catagen: this phase only lasts about 2 weeks and allows the hair follicle to renew itself.
Telogen: this is the resting phase where the follicle remains dormant, which can last for 1-4 months. Normally, 10-15% of the hairs are in this phase at any given moment. Once this phase completes, anagen begins again, and the existing hair is pushed out of the pore by the new growth and eventually sheds.
In layman's terms, DHT essentially attacks the head's hair follicle, lengthening the telogen phase, thinning the follicle and ending regrowth. Recession tends to begin by the temple and the back of the head and eventually spreads.
While scientists have not exactly pinpointed why some men are more susceptible to hair loss than others, they have theorized that it is likely due to the follicle receptors. Essentially, some men are more susceptible to the effects of DHT on the follicle (vis-à-vis the receptors) whereas others are not impacted by the androgens' effect on the head follicle. This is where genes come into play.
So while some myths claims that men with higher testosterone are more likely to lose their hair, it could be a correlation, but it's not a causation. It depends on the man's susceptibility to DHT, regardless of testosterone levels or not.
TREATMENT
There are hundreds of vaunted home remedies and pharmacy products that claim to cure male pattern baldness. Most of them are a scam.
Supplements, such as biotin, can improve the thickness of the hair follicle shaft, thereby giving the perception of thicker hair, but biotin's effects tend to be minimal. The way to halt male-pattern baldness is to stop the effects of DHT from "attacking" the follicle itself. This, in turn, will allow the follicle to remain in the anagen phase longer and regrow with a thicker shaft.
Finasteride (brand names: Propecia, Proscar) is an inhibitor of the enzymes that convert testosterone into DHT. Finasteride is believed to work on limiting the production of DHT in the prostate rather than actually work on the follicles themselves. In various studies, a side effect of finasteride can include a lower libido, but this has shown to be a side effect in only 1%-3% of men. The medication must be taken every day, otherwise, balding will continue.
In tandem with finasteride, a prescribed form of topical minoxidil, the ingredient found in Rogaine, can be effective in stimulating hair follicle growth. Minoxidil is believed to dilate the blood vessels on the scalp, whereby it thickens new follicular growth in the anagen phase. Minoxidil-tretinoin solutions are becoming more common, as tretinoin has been found to improve the efficacy of minoxidil. However, minoxidil will likely not be effective enough by itself to stimulate hair regrowth, as DHT will still continue to "attack" the follicles. Essentially, DHT will work against minoxidil's effects. Therefore, combination of oral finasteride + minoxidil will have the optimum effect.
If you are concerned about hair loss or believe that you are experiencing male-pattern baldness, go to your dermatologist or a dermatologist specializing in non-surgical hair-loss treatment. Surgical hair plugs are an option, but they will make no difference if the follicles are still under attack from DHT. Therefore, you must first solve the root of the problem before fixing it cosmetically.
If you have more questions related to hair loss, feel free to contact Brian for further recommendations.