Skin types and photobiomodulation: what impact does melanin have?

Skin varies from person to person. Its color, density, and sensitivity to light vary considerably depending on its melanin content. A question often arises among those interested in LED photobiomodulation: does this type of aesthetic treatment work the same way on all skin types? The answer is nuanced, and it deserves serious consideration.

Melanin, the pigment that interacts with light

To understand how LED light interacts with different skin types, we must first consider melanin. This pigment, produced by cells called melanocytes, is primarily responsible for skin color (known as skin type). The darker the skin, the more melanin it contains, and the more likely it is to absorb certain wavelengths of light before they reach the deeper layers of the dermis.

In photobiology, absorption is a prerequisite for any biological reaction. The emitted light energy is absorbed by chromophores—biological photoacceptor molecules (including melanin)—depending on the wavelength, to produce different biological effects. In other words, melanin is not merely a pigment: it is an active participant in the interaction between light and the skin.

In photobiomodulation, the wavelengths used play a crucial role. Red light is the visible color that penetrates deepest into the skin. It stimulates fibroblasts, thereby increasing the production of collagen and elastin, which are responsible for skin firmness. Skin with high melanin levels can absorb some of this light energy at the surface, which does not render the treatment ineffective but does require adjusting certain parameters.

A response that varies depending on skin type

Unlike other techniques such as laser hair removal (which specifically targets pigment to destroy the hair follicle), LED phototherapy does not seek to activate melanin but rather to stimulate cellular metabolism at a deep level. This explains a fundamental difference: LED photobiomodulation is suitable for all skin types, making it a remarkably versatile cosmetic treatment.

On fair to combination skin, red light penetrates easily into the deeper layers of the dermis to stimulate fibroblasts. This triggers the production of collagen and elastin; collagen fibers gradually reorganize, and skin regeneration becomes noticeable fairly quickly. Age-related loss of radiance, stretch marks, and loss of facial firmness respond well to this light therapy.

On olive or dark skin, melanin absorbs more energy at the surface. The treatment remains effective, but adjusting the wavelengths and intensity of the sessions can help optimize light penetration. LED light acts on melanocytes and melanin thanks to its deep penetration into the dermis, helping to reduce skin hyperpigmentation such as sunspots or post-inflammatory hyperpigmentation. For these skin types, LED photobiomodulation can therefore offer a dual benefit: acting deeply on cellular regeneration and helping to even out skin tone by balancing melanin production.

Here are the main differences observed based on skin type during the initial sessions:

• Fair skin: responds quickly to light stimulation, regains radiance after just a few sessions, and collagen production begins relatively early in the treatment course.
• Dark skin tones: Light penetration is slightly filtered by melanin, but the treatment has a real effect on collagen fibers and elastin when followed up appropriately.
• Dark skin: Melanin absorbs some of the energy at the skin's surface, which may require adjustments to the intensity, without compromising the visible results over the medium term.

The LED mask: a beauty treatment designed for everyone

One of the most accessible forms of LED phototherapy remains the LED mask, used in beauty salons or, for certain models, at home. When applied to the face, this device delivers LED light evenly across the entire skin surface. The wavelengths are selected based on the treatment goals: red light for skin regeneration and collagen production, blue light for blemish-prone skin, and yellow light for skin tone and circulation.

LED phototherapy therefore differs from laser hair removal in one key way: it does not aim to destroy pigmented cells but rather to provide non-invasive cellular stimulation. The principle of photobiomodulation involves exposing the skin to non-ionizing artificial cold light (LED), which deeply stimulates skin cells. The result: the treatment is gentle, painless, requires no recovery time, and can be performed year-round on all skin types.

Hyaluronic acid, often used as a complementary treatment, also sees improved absorption thanks to the effect of LED light on skin microcirculation. LED photobiomodulation thus maximizes the effectiveness of active ingredients applied before or during the treatment, making it a valuable ally in anti-aging skincare routines.

Results that stand the test of time

The question of the treatment protocol is often the first one asked by people who are new to photobiomodulation. Visible results depend on several factors: skin type, phototype, the desired outcome (anti-aging, radiance, stretch marks, loss of radiance), and the consistency of treatment. The skin appears brighter and more radiant starting with the very first sessions. The deeper effects, linked to the stimulation of collagen fibers and skin regeneration, gradually become more pronounced over several weeks.

The results of the treatment protocol are generally observed over the course of several sessions, at a rate of one to two per week. On the face in particular, there is an improvement in skin texture, a gradual tightening effect, and a reduction in age-related loss of radiance. Collagen and elastin, whose production naturally declines with age, regain a more active synthesis thanks to the regular application of red light.

Regardless of skin type, LED photobiomodulation has established itself as an accessible, gentle aesthetic treatment suitable for all skin tones, from the lightest to the darkest phototypes. Melanin, far from being an obstacle, is simply a factor to be taken into account when tailoring each treatment plan. It is precisely this adaptability that makes the treatment so effective.

See also:

• LED photobiomodulation: How does it work?
• Photobiomodulation: Dermatological Applications
• Photobiomodulation: Which device should you choose?