Hair loss is something that affects many people. In fact, up to 50% of the population is affected by hair loss or hair thinning at some time during their lifetime. Women can be especially concerned, because they wonder if this is related to an underlying medical condition, their hormones, a nutritional deficit, or stress. However, the reality for most persons with long-standing hair loss is that it is inherited.
How Does Hair Thin?
Hair grows in three cycles. Anagen is the actively growing phase, and hair spends 5-7 years in this stage. Then, it transitions through what is called catagen phase, which lasts 3 weeks, to the resting or telogen phase, which lasts 3 months.
Think of your hair follicles as little workhorses. You want them to spend as much time in the anagen phase as possible. However with male and female pattern hair loss, the follicles become lazy. They want to spend more and more time resting in telogen and less time growing in anagen. As the time hairs spend in anagen shortens, hair may appear to shed more. This is because the hairs are essentially turning over more rapidly.
There is another important difference in the quality of the new hairs. Instead of being as thick as the previous hairs, they are being replaced by thinner, finer versions of themselves. This is a process called miniaturization. The combined result is then two-fold—not only are the hairs less thick, but they stay in the actively growing phase for shorter periods of time. As the owner of these hairs, you are getting less and less bang for your buck!
Without any treatment, male and female pattern hair loss can be chronic and progressive. This means that the hairs will continue to thin and that the amount of time they are in the actively growing phase will continue to shorten. Overall hair density, which refers to both the thickness of hairs, as well as the number of hairs per square centimeter, will diminish.
How Quickly Does Hair Thin?
The rate of thinning is difficult to predict. Some may present with a rapid thinning over 6-12 months, while others may develop thinning slowly over a decade or more. This is also determined largely by genetics. For many people, their hair loss is unmasked by some major physiologic event such as having a baby or going on a crash diet.
Learn More About Post-Pregnancy Hair Shedding
At What Age Does Male and Female Pattern Hair Loss Generally Appear?
This can vary immensely. Some can present with hair thinning as early as their late teens or early 20s. Others may not present until their 50s or 60s. What is important is to get a diagnosis as early as possible. This may involve seeing a board-certified dermatologist or hair loss expert. This way, you can start on therapy as soon as possible to reverse the miniaturization process. Learn About Treating Hair Loss