Causes for Hair Loss
No one is 100% certain of what all the contributing factors may be in hair loss; however, it is believed that there is a link between male pattern baldness (MPB), also known as androgenetic alopecia, and androgenic hormones. In males, a hormone known as dihydrotestosterone (DHT) triggers androgen receptors in hair follicles on the top of the scalp. This activation of the hormone receptors changes the cells and reduces their cell growth activity. Over time, the hair follicle miniaturizes causing each successive growth cycle to get shorter and the hair follicles get thinner and smaller. The large terminal hair follicles turn into tiny unpigmented vellus hair follicles. Eventually, the follicles are no longer able to function properly and they completely disappear in men, though in women the follicles usually survive in their miniaturized state.
Balding in Men
In men, balding typically starts on the top of the head. In some men the hair loss can progress until there is nothing left but a fringe of hair around the bottom half of the head. Women’s hair loss is quite different from male pattern baldness as the hair loss pattern is usually a diffuse thinning over the top of the scalp, but it too is primarily hormonally driven. It has been noted that both the number of androgen receptors and the level of 5-alpha reductase, which converts testosterone to DHT, are higher in hair follicles on top of the scalp than in the rest of the scalp. This may partly explain why hair loss occurs in hair follicles on top of the scalp while hair follicles at the back and sides of the scalp seem more resistant to the androgen hormones.
Factors that cause hair loss
Hair Loss and other factors
In addition to androgens causing pattern baldness, it is believed that there are other factors that contribute to the condition along the way. Some suggest that inflammation may also contribute to hair loss.
Elevated androgens
Sometimes, but not always, hair follicles that are in the process of miniaturizing have inflammatory cells around them. A possible explanation for this inflammatory cells activity may be that elevated androgens also trigger increased sebum production, favoring an excess microbial and parasitic population leading to inflammation of the hair follicle. Doctors have found a strong correlation between early onset extensive hair loss and heart disease, so there may be a common etiology outside the androgen paradigm for pattern loss.
FDA Approved Treatments
Only two hair restoration treatments approved by the United States Food and Drug Administration (“FDA”) are available today and one medical device: minoxidil and finasteride. Minoxidil is marketed as Rogaine®. Finasteride is marketed as Propecia®. These two products can be effective in hair loss prevention and may grow new hair. However, once a patient begins using Rogaine® or Propecia®, he or she must continue to use the products indefinitely. If an individual stops using the drug, any new hair grown as a result of the drug will likely fall out. As with any drug, adverse reactions can sometimes occur.
There is only one medical device that has been cleared by the FDA known as
Low-level laser therapy (LLLT). The HairMax Laser Comb, from Lexington International, LLC manufactures the ‘only’ medical device that has been cleared for marketing by the FDA and is clinically proven to “Promote Hair Growth.”
