Permanent removal of hair by laser - is it really permanent? How long can the results last?
The answer to this question relies a great deal on understanding some key facts about how your body hair grows, and how laser hair removal actually works.
How Does Hair Grow?
Hair grows from structures named follicles underneath the skin. The root grows in the follicle, and the portion of the hair that can be seen above the skin is named the "shaft" of the hair. Your body hair grows cyclically. At any one point in time, the hair in some of the follicles will be actively growing; other follicles will be resting, and yet others will be in the process of shedding.
How Laser Hair Removal Works
Hair reduction or even permanent removal is now practical for most skin and hair colorings. Laser hair reduction therapy works by targeting hair root cells under the skin. It is possible for the laser rays to hone in on the hair root cells because of the melanin these cells contain, which makes them darker than the ambient tissues.
However, this does mean that the success rate of laser hair removal treatment is dependent on the difference in color between the hair root cells and the skin. That is to say, it works most effectively if you have very fair skin and very dark hair - where there is a strong difference between the dark color of the hair root cells and the light color of the ambient skin tissues.
Even in ideal scenarios, however, the lasers do not kill off all of the hair. Why? Due to the fact that the lasers can only target actively growing hairs. As we learned earlier, only a proportion of the body hair in any one part of the body will be actively growing. This is why laser hair removal treatments are usually spaced several weeks apart - so that different follicles will be active at the next visit, and can be effectively treated.
Because of the mechanism by which laser hair removal works, while it may disable a significant proportion of the follicles it will not cause a 100% stoppage in all body hair growth in the treated area. However, an 80% reduction in hair is entirely possible - permanent laser hair removal is a truly viable solution for undesirable hair growth.