Laser hair removal destroys hair follicles, but not every single hair and not on every part of the body. Here is what you can expect from a series of treatments. It is one of the questions I hear most often, and the honest answer depends on the colour and thickness of the hair, the body area and what is happening with your hormones.
You always need a series of treatments, usually 3 to 6. The intervals depend on the area: about 4 to 5 weeks on the face, roughly two months for the underarms, bikini line and torso, and about three months for the legs. So laser hair removal is a process spread over time, not a one off visit.
It is simplest on areas not linked to hormones, such as the calves, thighs, underarms and bikini line. With dark hair the reduction there is clear, because the follicles that produced it are removed. I have been doing laser hair removal since 2005 and I have never met anyone whose laser removed hair grew back. Still, it is impossible to remove every last one, so single hairs may remain.
I am an example myself. I had my bikini line done four or five times, the last time in 2008, and my hair there was not particularly dark. To this day I have only a few single hairs left, with a completely different texture.
It is different with light, fine hair. Such hairs cannot be removed completely, and light vellus hair remains. That is why at the first visit I always assess the colour and thickness of the hair, so you know from the start what you can count on.
It also happens that I refuse to do the treatment, and not rarely at all. I do so when I believe the hair is not suitable and the treatment will not give results. The same goes for a client who says she cannot stop herself from plucking before the visit.
Hair can also change its character under the influence of hormones. Usually nothing new appears; instead, a follicle that used to produce light vellus hair starts producing dark, coarse hair. This is mainly caused by androgens, and follicles in different parts of the body respond to them with different strength.
On areas not linked to hormones, something really significant has to happen for hair to come back. Pregnancy is a good example. Many women then notice dark hairs on their thighs, especially on the inner and back sides. Very often after giving birth, once hormones settle, these hairs go back to being light vellus hair on their own.
On the face, abdomen or chest, the hormone dependent areas, the body can keep turning vellus hair into dark hair. That is why after the series is complete, top up visits are sometimes needed, every six months or once a year. Sudden changes can also have a medical cause, so if hair is increasing quickly or appearing where it never grew before, it is worth seeing an endocrinologist.
Shaving is a separate matter. There is no research confirming that shaved hair grows back stronger, and I was already asking that question at university. My observations in the clinic are different, though. When you start shaving vellus hair, over time it becomes stronger, coarser and darker.
You can see this clearly on the calves, where hair is soft at first and becomes coarse after years of shaving. On the other hand, women over sixty who never shaved their legs, because smooth skin was not the norm back then, often find their calf hair has simply worn away. The follicles are there, they just do not produce hair.
I am most careful about this with the face. Hairs must not be plucked before the treatment, so I ask clients not to shave the whole area with a razor, but to use small round tipped scissors to trim only the dark hairs we want to remove. Shaving the whole area takes the vellus hair with them, and it can then grow stronger, turning a small problem into a bigger one.
I remember a client from fifteen years ago whose forearms I did not want to treat, because the hair was too light and too weak. She came back after more than a year of regular shaving, and then the treatment could be done. I do not think it was wise, but it shows well how shaving can change hair.
Age matters too. When I started working twenty years ago, I only treated people over 18, because puberty lasted longer then and hair appeared later. Today puberty in teenagers progresses faster, so I agree to treatments from about 16 if the hair is strong, dark, dense and causes real discomfort.
I always warn, however, that at this age the process of hair appearing may not yet be finished, so in the following years hormones may still affect hair all over the body. A minor must come to the treatment with a legal guardian who gives consent. I am already treating the next generation, as many clients send me their daughters.
So I answer the question in the title honestly. On areas not linked to hormones, hair that we remove does not come back in my experience, although single hairs and light vellus hair may remain, especially with weaker hair. On hormonal areas and with changes in the body, such as pregnancy, you need to be prepared for the hair to change.
At the clinic in Osielsko, near Bydgoszcz, we always start with a conversation and a hair assessment, because only then can we honestly say what to expect in a specific case. You can also come just for a chat, ask about anything that worries you, and only then decide whether you want to begin. This is how we work across the whole clinic, in the spirit of slow age: calmly, without big slogans and with realistic expectations.
Katarzyna Gwizdal, MSc, cosmetologist, Skin Laser