Literally, people think that if you take it off, you will “never” grow armpit hair again, and your armpits will be clean from now on! In fact, according to the medical definition, as long as the hair follicle does not grow for more than one “growth cycle”, it can be called “permanent hair removal”.
Therefore, the medical profession can generously say that this is “depilation and depilation”, but people feel that “how come there are still hairs growing out”? The resulting gap is often the source of disputes.
Explain the principle of laser hair removal:
Most people may think that laser hair removal is to use laser to directly hit the hair follicle (as shown in the figure), resulting in the destruction of the hair follicle and the apoptosis of the hair follicle.
In fact, the laser of laser hair removal does not really hit the hair follicle, but the hair on the surface of the skin, causing the temperature of that hair to rise, and the heat energy will be transmitted to the whole hair. If the hair itself is in the “growth period”, the heat can be transmitted to the hair follicle smoothly, resulting in the apoptosis of hair follicle and successful hair removal.
This is also why most hospitals recommend scraping the hair 1-2 days before laser hair removal, so that the hair growth just protrudes from the skin surface by about 1mm.
Therefore, it can be expected that when we come to the hospital, the hair on our body actually contains hair in different periods, and the effect of laser hair removal is also those in the growth period, there will be quite a lot of missed fish.
Moreover, because everyone’s hair growth cycle is quite different, it can only be “estimated” to estimate “how many times and how long it takes”, and there can be no real accuracy.
In fact, there are considerable individual differences in the proportion of each person’s hair in the growth period and in the rest period. This is also a big factor why some people feel that the effect is super good at one time, but some people are not as effective as expected.