LASER HAIR REMOVAL FOR DARKER SKIN
WHAT ARE THE OVERALL EFFECTS OF UVR on MELANIN
Our skin is a complex organ and protects our organs from the outside world of pollution and pathogens. Our skin is a safety barrier and keeps all our organs in one body. One type of cell our skin produces is Melanocytes which give off melanin, a pigment that is present in the human hair, eyes and skin pigment. Melanin provides protection from UV rays by absorbing, thus fighting against sun damage and protecting DNA stored in cells .
The production of melanin is directly affected by the amount of UV rays we absorb from the sun. The melanin absorbs the UV, ultraviolet A (UVA),Ultra violet C( UVC) and blue light. rays project it towards the upper layers of the epidermis.
UVA rays have the least energy of all UV rays and a longer wavelength . UVA rays are specific in causing the skin’s cells to age . Furthermore, it contributes to premature aging, and wrinkling. A majority of the sun's rays that reach humans are UVA rays . UVC rays have more energy in comparison to UVA rays and they are the most damaging type of UV rays. . Radiation from these rays will cause sun burns and certain eye injuries. The only way humans are exposed to this is by artificial lighting, such as tanning beds.
An ongoing exposure of UVA and UVB and even UVC rays can cause photoaging, which is premature aging of the skin and increases the risk of skin cancer.Photo aging can change DNA sequences thus leading to cancer. Leading to an unregulated DNA sequence.
However, the more melanin present in the skin, are less likely to see the effects of these UV rays. This is because the Melanin is constantly redistributing the UV rays that are absorbed into the skin, thus protecting the DNA. Someone of a light complexion will see the effects of UV rays more rapidly due to the lack of Melanin. Signs of freckles, dark marks, and people who are easily burning in the sun are signs that the sun has already taken a toll on the skin.
Melanin is a pigment produces in the cells by melanosomes. Each layer of basal cell, from the deepest layer of the epidermis, is connected to approximately 40 keratinocytes and one Langerhan cell. Both the keratin protein and langerhan cells protect the hair skin and nails. Langerhan cells are a type of cell that reside in tissue-resident macrophages that provide a dense network of immune system responses. These cells activate immune responses and interpret the correct micro environment in which to start an active immune response. These cells are macrophages. Which means they are a part of the white blood family, and remove goring microorganisms and remove other dead cells. Keratinocytes provide melanocytes with nutrients to synthesize more melanin.
Every skin color has melanin. However, Eumelanin is the black or brown pigment that protects the cells. Melanin has a “shielding “ effect which is a physical barrier which scatters the UV rays. It also absorbs and filters which reduces the penetration of UV deeper to the epidermis. The melanosomes in dark skin are less prone to degradation by the lysosomal enzymes because they remain intact throughout the epidermis. Melanocytes are related to lysosomes. This is because they both kill unwanted material . Melanin forms supranuclear caps in surrounding keratinocytes. Which contribute to sun protection. A supranuclear cap is a build up of melanin around the nucleus thus making it more difficult for UV rays to penetrate the cell's nucleus.
The UV rays that are absorbed and eventually scattered through the epidermis, are mostly scattered through the thickness of the stratum corneum. Which is the upper most layer of the skin. In brown and black skin, te sun damage was only present in the upper layers of the epidermis. And was present in all layers in light skin. In addition to UV rays being less harmful in darker skin, the rate of apoptosis in darker skin is significantly higher. Thus, leading darling skin to be more rapid in removing damaged cells. The combination of darker skin, due to decrease in UV ray damage and the rate of apoptosis in darker skin, leads to a greatly reduces risk of carcinogens being produced.
HOW DO LASER EFFECT MELANIN
The usage of lasers are a great medical tool that can be used for removing hair, getting rid of fine lines and wrinkles, and even tightening loose skin. A laser is extremely beneficial for permanently destroying hair follicles, and causing trauma to the skin which produces collagen. Popular areas for laser hair removal are the upper lip, legs, underarms, and chin. A laser is drastically different from cosmetic procedures such as tanning beds because it does not involve UV radiation.
When using a laser, the targeted area is heated up. After, the pigment inside heats up hair and kills the follicle. Needless to say, laser hair removal works best with dark hair since it attaches to the pigment. And new technology allows darker skin tones to get treated for permanent hair removal. Prior, only people with light skin and dark hair were good candidates for treatment because the laser would sense pigment from the hair rather than the skin.
The term laser is often associated with high frequency waves. Which leads a lot of people to believe UV rays are being used in this process. This is incorrect. UV rays are extremely harmful. These rays are usually seen in tanning beds. On the other hand, lasers are monochromatic light that releases a steady stream of photons, which is a particle of light. Lasers used for hair removal are often red. This is because red is the lowest frequency wave. This is less harmful than purple waves which have a higher frequency.
Laser hair removal does not use any range of UV rays but uses visible light energy. The light energy in a laser is low frequency waves and are not so energetic. Which is why most people require multiple treatments. The success of laser treatment is influenced by the person's skin color and hair color. Laser hair removal technology has been newly developed, in order to provide darker skin tones with treatment. These lasers are able to detect excess pigment in the hair follicle. It operates by producing a longer wavelength that penetrates deeper into the skin and is able to bypass melanin in the upper skin. The hair bulb is located in the dermis of the skin. Thus, these lasers do not impact the epidermis.
Tyrosinase is an enzyme that catalyzes melanin production. This hormone is often activated by hormonal factors, increased in vitamin D, or by the post inflammatory responses commonly known as hyperpigmentation. Often, if the laser is used too often, or the frequency of the waves are too strong, tyrosinase is activated to increase the rate of melanogenesis of the skin. As the skin sheds upward, pigment granulocytes change the color to the injured or inflamed area to a darker appearance. Along with hyperpigmentation, melasma is a common facial hyperpigmentation. Melasma appears on the skin in brown patches. Other things such as forms of north control, and sun exposure can prolong the healing time for these spots. Despite irritation from lasers, the correct laser can remove these dark spots. One excellent example of a laser is the Fraxel laser, or CO2 laser. People who fit the Fitzpatrick skin types I-III are great candidates. The fraxel can also reduce freckles, sun spots, and signs of aging. The Fitzpatrick skin scale was invented in 1975. His model separates skin types by skin color, ranging I-VI, lightest to darkest, this scale also maps out undertones of skin, and determines how easy skin will burn. A laser for darker skin is the Clear+ Brilliant, which gives the same outcomes of the Fraxel, but is accessible to all skin types.
REFERNCES
1, Park DJ;Jeon G;Bang SH;Kim SY;Wee JH;Kim YH;Min J; (n.d.). Cellular lysosomes’ activity for melanin reduction on artificial skin tissue. Molecular biotechnology. https://pubmed.ncbi.nlm.nih.gov/31894512/
2.Brenner, M., & Hearing, V. J. (2008). The protective role of melanin against UV damage in human skin. Photochemistry and photobiology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2671032/#R65
- Chits, D. aesthetics. (2023). Can laser hair removal cause cancer?. Dermadoc. https://www.dermadoc.co.uk/can-laser-hair-removal-cause-cancer.php
4.Ultraviolet radiation. Ultraviolet radiation - Energy Education. (2013). https://energyeducation.ca/encyclopedia/Ultraviolet_radiation#:~:text=Ultraviolet%20radiation%20(UV)%20is%20a,wavelengths%20between%2040%2D400%20nanometers.
5.Post laser hyperpigmentation - melasma & dark skin. Dr. Michele Green M.D. (2022, September 22). https://www.michelegreenmd.com/post-laser-hyperpigmentation