The Science Behind Laser Hair Removal
How Laser Hair Removal Works
At its core, laser hair removal is all about using light to disrupt hair growth. Here’s a breakdown of the process:
The Laser Targets Pigment: The laser emits a specific wavelength of light that is absorbed by the pigment (melanin) in your hair, specifically in the hair bulb and bulge. This is why laser hair removal is most effective on darker hair—there’s more melanin to absorb the laser’s energy.
Heat is Generated: As the pigment absorbs the light, it converts it into heat.
Follicle Damage: The heat generated by the laser damages the hair follicle, impairing its ability to produce new hair. Over time and with repeated treatments, this damage can lead to a significant reduction in hair growth, and in many cases, the follicle may stop producing hair altogether.
Understanding Hair Growth Cycles
To appreciate why multiple laser hair removal sessions are necessary, it’s important to understand the hair growth cycle. Hair grows in cycles, and not all hairs are in the same phase at the same time. The hair growth cycle has three main stages:
- Anagen (Growth Phase): During this phase, the hair is actively growing and has the most melanin present, making this stage the most responsive to the laser.
- Catagen (Transitional Phase): In this brief phase, hair growth slows, and the follicle begins to shrink. Laser hair removal is less effective during this stage because the hair is no longer fully connected to the follicle.
- Telogen (Resting Phase): The hair is fully detached from the follicle and eventually falls out. Since there is no active hair growth, the laser cannot target the follicle effectively during this phase.
Because hair is in different stages of growth at any given time, multiple treatments are needed to catch as many hairs as possible in the anagen phase. This is why laser hair removal typically requires a series of sessions spaced several weeks apart. Once many of these cycles have been targeted, treatments are spaced out periodically (around 2-4 times a year) for the average client.
Everyone is Unique- Down to Each Follicle
There are many reasons for hair growth from genetics, hormones, age, pregnancy, diet and lifestyle, medications, and overall health. Each of these factors play a crucial role in not only hair growth, but the thickness or composition of the hair itself as well as Fitzpatrick Skin Type. This is why each individual may need different parameters as well as number of sessions to provide the results that both you and your professional are looking for. If you are an individual who experiences more frequent and stubborn hair growth, this does not necessarily mean that laser is ineffective for you, but that more frequent and consecutive sessions are necessary to effectively target the active growth cycles that are occurring. During the maintenance phase, sessions are usually scheduled more periodically, around 2-4 times a year for the average client.
Types of Lasers Used in Hair Removal
Not all lasers are created equal. Different lasers are designed to treat different skin types. Here’s a look at some of the most commonly used lasers in hair removal:
Ruby Laser: One of the earliest lasers used for hair removal, the Ruby laser operates at a wavelength of 694 nm. It’s most effective on fair skin but is less commonly used today due to the development of more advanced technologies.
Alexandrite Laser: This laser operates at a wavelength of 755 nm, making it ideal for people with lighter skin tones.
Diode Laser: Operating at a wavelength of 800-810 nm, the diode laser is effective for both light and medium skin tones.
Nd:YAG Laser: With a wavelength of 1064 nm, this wavelength is best suited for darker skin tones. It penetrates deeper into the skin, by passing the melanin in the epidermis and targeting the hair follicle directly, reducing the risk of hyperpigmentation or burns.
Final Thoughts
Laser hair removal is a powerful technology that offers a long-term solution to unwanted hair. By understanding the science behind the process, you can better appreciate how it works and what to expect from your treatments. The key to success lies in choosing the right laser, professional, and committing to the full course of treatments to achieve the best results.
In our next post, we’ll dive into what you can expect during a laser hair removal session, from preparation to aftercare, so you can feel confident and prepared for your journey to smoother skin.