This question comes up a lot. Why? Because there is not really a definitive answer. It will depend on quite a few factors. These include the location of the hair, your skin type and its colour, and how thick the hair actually is. Also, your gender will play a part, as may your current health. This article will attempt to get as close as possible to answering the hair reduction question.
Why Are Six Sessions Recommended?
Most hair removal clinics suggest six sessions because that is the average number of sessions the average person needs to achieve an 80-90% reduction in their hair growth, as an average over all body parts (not including the scalp). You will notice a lot of ‘averages’ in the previous sentence. This is because every person is different, and we can really only give a good educated guess as to the number of sessions required.
The Hair Phases
To answer the question further, we should explain that hair grows in 4 phases, collectively known as the hair cycle.
1. Anagen: The Growing phase
2. Catagen: The Transition phase
3. Telogen: The Resting phase
4. Exogen: Shedding phase
The fact of the matter is that lasers cannot target hairs in the catagen or telogen phases, just the anagen phase. The Exogen phase does not really come into the equation, as hairs are falling out anyway in this phase.
To make matters more complicated, while 85-90% of hairs on the scalp are in the anagen phase, this number is significantly lower for body parts, in varying degrees. Body hair is in the telogen phase for a lot longer, this is illustrated by the fact you cannot grow body hair to a long length when compared to scalp hair. Body hair rests more, and this resting phase is different in different body parts.
All hairs are not in the same phase at the same time
If they were, hair would not be efficient in its job as you would have periods of time with no hair. Every hair is on its own individual cycle. This is why sessions must be spaced apart. If you had a hair removal session too close to the last (in which you targeted hairs in the anagen phase), not enough hairs would have reached this phase again for the removal process to be effective. You would not be targeting enough hairs.
Other Factors To Consider
Before we look into the numbers, if you are stressed or in below optimum health, your body will have more hairs resting. This means that the laser will target fewer hairs. Your individual genetic makeup also has a bearing on the number of hairs that grow and rest.
Hair Removal in Numbers
We need to employ some maths to get further into the question of session numbers.
In one study we referenced here, the hair cycle was studied in both males and females. In thigh hair, for example, It was found that hair had a total cycle of 151 days in men, with hair being in the anagen phase for 54 days. For women, these numbers were 84 days full cycle and 22 days in the anagen phase. We can calculate the approximate number of hairs in the anagen phase at any given time from these two numbers.
So 54/151×100 = 35.76 for men and 22/84×100 = 26.19 for women.
Here is a table for men’s thigh hair removal with numbers rounded up for simplicity.
Men’s Thigh Hair Removal
| Session Number | Hairs at Start of Session | Hairs Removed | Hairs Remaining After Session |
| 1 | 10,000 | 3,576 | 6,424 |
| 2 | 6,424 | 2,297 | 4,127 |
| 3 | 4,127 | 1,475 | 2,652 |
| 4 | 2,652 | 948 | 1,704 |
| 5 | 1,704 | 609 | 1,095 |
| 6 | 1,095 | 391 | 704 |
Women’s Thigh Hair Removal
| Session Number | Hairs at Start of Session | Hairs Removed | Hairs Remaining After Session |
| 1 | 10,000 | 2,619 | 7,381 |
| 2 | 7,381 | 1,933 | 5,448 |
| 3 | 5,448 | 1,427 | 4,021 |
| 4 | 4,021 | 1,053 | 2,968 |
| 5 | 2,968 | 777 | 2,191 |
| 6 | 2,191 | 574 | 1,617 |
So, How Many Sessions Do I Actually Need?
The tables give the answer. For men, roughly 93% of hairs were removed after six sessions. In women, it was 84%—so approximately six sessions to remove this much hair. This is why sometimes you will need more sessions.
The Caveat
Your hair may be different to the hairs in our referenced study. You may be more or less stressed, your genetics will be different, and your hair may be thicker and darker.
We have the best laser hair removal device on the market at the Doctors Laser Clinic. This, coupled with experience and science, will give you the best chance of removing the most hair in the shortest amount of time.
Hair removal for you
If you would like to know more, get in touch. We are more than happy to explain any part of the process. If you are ready, book a consultation by contacting us here.
