Actually, hair doesn’t grow back, it just grows. Cutting or shaving the hair has no effect on its natural growth cycle. Depending on where it is on the body, hair grows about 1 cm per month. It goes through a growth phase, followed by a transitional phase and finally a resting phase before falling out of its follicle. Even though this process happens all over our body, we may not always be aware of it because we don’t really notice the hairs falling out unless we see them on our pillow or in the shower.
A hair cut in its growth phase will simply continue to grow at its usual rate until the end of its cycle. If the hair is cut during its transition or rest phase, it will simply stay at the cut length until it falls out or is replaced by a new hair. It may seem to us that the hair is growing back progressively but in fact, it is simply following its natural cycle until it is replaced by new hair. As such, a teenager who now only needs to shave one side of his face, will not have more hair on that side of his face 5 years later.
The razor cuts the exposed part of the hair. The hair seems thicker because it has been cut bluntly by the blade and lost its tapered end. This can give the impression that the hair is growing back faster and darker.
There is, however, an exception to the “shaving doesn’t make hair grow faster” rule. The rubbing of the razor does create an abrasion that stimulates blood flow (hyperemia), and it is possible that this increased blood flow can help the hair grow. This only holds true, however, in cases where the hair follicle is located in the epidermis (i.e. almost at the surface of the skin) like on a woman’s upper lip for example. As such, a woman who decides to shave the peach fuzz on her upper lip may, in fact, be encouraging hair growth in that area.
Today, rather than shaving, many hair removal methods with lasting results are available to us. With electroepilation and photo epilation, hair growth can be effectively reduced if not completely eliminated. In fact, electroepilation is a highly recommended method to remove facial hair as it requires no shaving prior to treatment.