It happens. If your lovely head of hair is starting to thin, it can be very troubling. Let’s examine the science behind hair loss and what can be done about it.
Most hair loss is classified as “androgenic alopecia” (AGA) and is responsible for 95% of all baldness. Significant hair loss will affect 50% of men by age 50 as well as 25% of women. For men, the hair loss begins in puberty and continues steadily until at 70 years of age, 80% of men will be affected.1 The condition is known as male pattern baldness (MPB) and is characterized by hair shedding from several areas of the scalp (the top of the head and the temples), which leave a typical horseshoe shaped hairline2. For women, the hair loss develops as a thinning at the vertex (top of the head) and is referred to as female pattern baldness (FPB).
For men, MPB has a hereditary component – it is inherited on the X chromosome that you get from your mother. But that isn’t the entire picture. It is now considered to be a “polygenetic” condition that is influenced by various genes from both parents. Further, FPB, which has not been studied as much, has a different pattern of inheritance.
If you have noticed thinning of your hair, a consultation with your doctor is warranted. Although most hair loss is genetic and age-related, there are some treatable medical conditions that can cause the problem. These include: iron deficiency anemia, hypothyroidism, Cushing’s disease, poorly controlled diabetes and certain medications. Additionally, women with elevated testosterone may experience thinning of the hair.
MPB is gradual and likely a result of susceptible hair follicles becoming smaller due to an increased uptake, metabolism and conversion of testosterone to dihydrotestosterone (DHT). Once hair loss begins, it will continue steadily without treatment. Many men are tempted to try the myriad of shampoos and topical concoctions that suggest they can block this process and stimulate hair growth. Dr. Evan Rieder, a dermatologist at NYU Langone Health (New York University), has been quoted as saying; “I find it very difficult to believe that something that’s applied to the scalp and rinsed off is going to have any appreciable effect (on MPB)”. Likewise, be aware of “special” vitamin and mineral supplements have not been shown to slow the progression of MPB. Save your money for treatments with proven efficacy.
Women who suffer with seborrhoea, acne, hirsutism (excessive hair growth), or alopecia (unexplained hair loss), should have endocrine blood tests ordered by their physician to determine the cause of FPB. These tests may include:
Abnormalities in any of these blood tests may suggest a treatable cause of hair loss.
As stated previously the pattern of hair loss in MPB is distinct – frontal-temporal (forehead and sides of the head above the ears), as well as “vertex” (top of the head at the back) is seen in men.
Figure 1. Norwood Hamilton classification of MPB3
Women tend to maintain their frontal hairline while losing hair more diffusely off the top and sides of the scalp.
There are several treatments for baldness caused by AGA, including oral and topical medications, laser therapy and surgery. The two medicines available are oral Finasteride (Propecia, Proscar) or topical Minoxidil (Rogaine).
Topical Minoxidil (solution, foam) was previously available only with a prescription. It can now be obtained over-the-counter. Minoxidil (Rogaine 5%) is a vasodilator that purports to stop further hair loss and has been deemed helpful in up to 70% of men who have tried it. Women may also chose to use this preparation and some 50% will get minimal hair regrowth while about 13% will have moderate regrowth. The side effects of Minoxidil include irritation (burning, itching, redness), and 3–5% of women will develop facial hair growth. Minoxidil treatment must be continued indefinitely to maintain the hair growth. If you stop it, the problem comes right back. A reasonable trial is one year. After that, if it hasn’t worked, it’s not likely to.
Finasteride (the active ingredient in the brand Propecia) is for men ages 18 – 41. This medication works by reducing the amount of DHT (dihydrotestosterone) in the bloodstream that causes miniaturization of the hair follicle resulting in steady hair loss. Finasteride is a prescription oral medication that is taken once daily. Its side effects include decreased sexual function, depression and decreased PSA (prostate specific antigen) levels – by up to 50%. Because of this latter effect, men need to be screened for prostate cancer prior to treatment and follow-up PSA levels must be interpreted accordingly. Finasteride does not “cure” AGA. If it is stopped the hair loss will return.
Women must NOT use Finasteride as it is a teratogen (an agent which causes birth defects). There is also poor evidence that Finasteride will work for women beyond childbearing years.
Men can use both topical (Minoxidil) and oral (Finasteride) medications at the same time.
Other medicinal choices for women are Aldactone (spironolactone) and Androcur. These medications are anti-androgenic in nature. Basically, that means they will lower testosterone levels in women. Yes, testosterone is the male hormone, but women also have testosterone in much lower quantities than men (as men have the female hormone, estrogen, in much lower quantities.)
An excellent review of the controversial subject, female pattern hair loss can be found HERE.
One treatment for hair loss that has been gaining popularity is low-level laser therapy (LLLT). LLLT works by stimulating the hair follicles in the scalp thereby “regenerating” the follicular unit’s ability to grow hair. Whether or not LLLT works is controversial. While some practitioners have reported significant improvement in hair growth, long-term studies showing consistency and efficacy are lacking.
LLLT is expensive and time-consuming as 2-3 times weekly sessions are mandated. However, LLLT does seem to be safe for both men and women with genetic hair loss. A thorough review of this modality can be found HERE.
The surgical option for areas of the scalp completely devoid of any hair is hair transplant. This involves removing strips of scalp with intact hair follicles to the areas without any hair.
Back in the 1950’s, the first hair transplants were tedious, painful, and had less than cosmetically perfect results. Technology has advanced such that modern day procedures have improved greatly. Many patients are very pleased with the results. The procedure usually requires three to four operative sessions over two years before adequate hair density is achieved. Side effects of hair restoration include:
Hair restoration surgery is expensive. You can expect to spend anywhere from $5000 to $15,000 depending on the extent of your hair loss. Women, too, have been exploring this procedure to restore their full head of hair.
Interestingly, in recent years baldness has come into vogue. Celebrities in film, music, sport and even politics have “embraced” their receding hairlines and have established that “bald is sexy”. Perhaps your inevitable hair loss is a good thing?
Genetic hair loss is very common among both men and women and certainly can be very distressing. Today we have a number of treatment options. Consult your family physician to explore the diagnosis and treatment of your condition.
For a complete review of this topic, I recommend any of the following resources:
Hereditary Patterned Baldness (Harvard Medical School)
Hereditary Hair Loss (Health Navigator)
Treating Female Patterned Hair Loss (Harvard Medical School)
References:
© November 1, 2020, Dry Shannon Lee Dutchyn, MD, CCFP, FCFP
