Hair Growth Cycle. When men see a pile of hair on the bathroom floor, they usually ask themselves a couple of questions. First of all, when did I last vacuum here? And, why is there so much hair on the floor and not on my head?

Switching to the serious side of this point, it is indeed frustrating to see your hair fall out, and research shows you’re not alone. On an average, we all have around 100,000 hairs on our scalp, and we lose about 100 hairs a day. We all undergo a natural hair life cycle where a large majority of hairs on our scalp continuously grows while a minority sheds. It is when this cycle is disturbed that leads to hair loss. Let’s deep dive to understand this better.

1. Anagen Phase: the hair is growing

During the anagen phase, your hair grows at an average rate of ½ inch per month. The length of this growing phase determines the maximum length of hair. For most people, this can be anywhere between 18 and 30 inches.

Typically, these hair growth cycles occur every two to six years. Yes, that’s a long time to grow hair. But how do we explain things like hair loss and male pattern baldness when our hair grows back so frequently? The answers lie in the following stages of hair growth.

2. Catagen Phase: the hair falls
   

Once your hair has completed growing, it enters a transitional phase called Catagen. By “transition” we mean when your hair starts falling out.

This is not as bad as it sounds, and the science behind it is very interesting. Your hair receives a certain signal from your body telling it to stop growing, and your follicles react by shrinking slightly and separating from your blood supply.

When you see the word “decoupling”, you might think that at this stage your hair will fall out and you’re doomed to go bald forever. The good news is that when it comes off the scalp, it usually doesn’t fall out until the new hair starts to push up.

3. Telogen Phase: the hair is resting

When your hair falls off your scalp, it enters a resting state called telogen. Your dying hair only stays on top of your head for three to five months before finally being pushed out by brand new hair.

However, this stage is by no means easy. Researchers at Harvard Medical School describe a condition called telogen effluvium. It’s a very fancy term used to describe the phenomenon of bodily changes or unexpected stressors accelerating the telogen phase. People with telogen effluvium lose over 300 hairs per day compared to the typical 100 we mentioned earlier.

4. Exogen Phase: the hair is shedding

Your hair goes through a lot before it reaches the exogen stage. Once your new hair grows in, the old hair will completely fall off the scalp and start to fall out in large quantities. While you’ll usually notice this after brushing your hair, you’ll also see clumps of hair running down the shower drain or styling.

What happens to hair loss during these stages?

Not all hair growth cycles are considered equal. When male pattern baldness begins, the hair follicles become smaller, making it difficult for hair to grow. In addition, Evolved Clinics hair loss expert, Paul Green points out that the anagen phase becomes shorter, while the telogen phase remains the same or even increases.

As research has shown, this phase reversal has something to do with your genes. While this means you can’t control whether or not you’re affected, you can prevent it from getting worse with treatment.

What effects, do hair loss treatments and transplant have on the hair growth cycle?

DHT is a male sex hormone that usually helps your body develop muscles and facial hair. In men with male pattern baldness, DHT also starts to attach to your hair follicles, making them smaller and smaller until they no longer grow hair.

However, DHT does not do this alone. Like any villain, it does this with the help of a partner, an enzyme called 5α-reductase. Finasteride stops the production of 5α-reductase. This means that DHT cannot get the boost it needs to miniaturize the hair follicle.

Minoxidil works a little differently. It helps increase the size of anagen hair follicles (remember, hair loss occurs in men when these follicles get smaller and smaller) and reduces the duration of telogen. This means your hair will be healthier and grow more frequently.

And hair transplant is the only permanent solution as it redistributes the hair from the back of your head i.e. hair which is immune to DHT and implants it to the front/ top of the scalp where it’s needed.

We talk a lot about science here, and for good reason. The bottom line is that every man’s hair grows (and falls) at a different rate, but they all go through the same stages. Because of this, knowing each stage of hair growth cycle makes it easier to assess your own hair loss and better understand how a hair transplant or other hair loss treatments can help.