One of the most heart-rending movies I have ever seen is For Colored Girls.
In the midst of a gripping story, I noticed Phylicia Rashad, playing the role of a kind neighbor, and was struck by her beauty and well-defined facial features. I didn’t know it at the time, but she would subconsciously become my mind’s view of the statement, ‘Black don’t crack.’
This expression is used to signify the seeming delayed visible aging in Black people, which is commonly attributed to the fact that they produce more melanin.
Some schools of thought also suggest that because of this, dark-skinned people don’t need to use sunscreen.
What is melanin and is it really that powerful?
Does it truly give any of us anti-aging properties?
What exactly does it do - just in case it doesn’t?
Let’s find out!
Do you know effervescent Vitamin C tablets? Those that when dropped into water sizzle, with the orange colour spreading as it is distributed, till it gets to the top of the glass?
Melanin's movement in your skin is similar. It goes from deeper layers of the epidermis (basal layer), where it is produced by melanocytes, to the surface layers, where it works internalized by keratinocytes.
Yes! Melanin does give your skin its characteristic colour. What you may not know is that melanin does not work alone. It works with other compounds like nucleic acid, carotenoids and oxy/deoxy-haemoglobin. It also gives your hair colour, thanks to melanocytes in hair follicles, and determines eye color.
Your body produces three forms of melanin:
Eumelanin (brown-black pigment): This is the major pigment that gives the skin its colour. It is also responsible for the skin's levels of ultraviolet rays (UVR) sensitivity and cancer risk.
Pheomelanin (yellow-red pigment): Gives the skin on the lips, vagina, glans penis, and the nipples their pinkish hue.
Neuromelanin: This is a part of the nervous system and pigments the brain.
Photo by scienceABC
So, if we all have melanin, why do our skin and hair colours differ?
Everyone has the same number of melanocytes (cells that produce melanin). What makes us different is the number, occurrence, packaging and size of melanosomes (the containers, within melanocytes, where melanin is stored and distributed.)
This leads to differences in the amount of the different kinds of melanin produced, and skin pigmentation.
Is it possible that my melanin is not produced properly?
Just like most active substances within the body, there could be defects in the process of melanin production and transport. These could contribute to many skin conditions. Some may be inherited, like in albinism, or autoimmune disorders like vitiligo or Parkinson’s disease.
Melanin does protect against the sun but… not as much as you think.
10% of the rays released from the sun are ultraviolet (UV) rays.
Melanin absorbs 50-75% of UV rays, which is great. However, the amount that penetrates the skin, directly or indirectly, can still cause harm to our skin's health. This could lead to short- and long-term photo-damage effects like erythema, skin wrinkling, increased risk of skin cancer, hyperpigmentation among others.
When we are exposed to sunlight, the UV rays cause the skin to produce more melanin to attempt to protect us from the harmful processes that can take place.
In this way, the melanin acts as a natural sunscreen leading to skin tanning.
If the melanin protects me, do I still have to wear sunscreen?
Short answer, YES.
Here's why:
Imagine this; You went for a run and it’s been 30 minutes, so you are thirsty. You need a glass of water to make you feel human again, but all you get is 10 drops.
Would you still be thirsty? I bet you will! This is how melanin works too.
Black epidermis is more effective in blocking UV penetration (allows about 7.4% of UVB and 17.5% of UVA) when compared to White epidermis (allows passage of 24% of UVB and 55% of UVA.)
Darker skin tones allow a lesser amount of the sun’s rays to penetrate the skin, when compared to lighter skin tones. However, when viewed as a sunscreen, melanin offers only about SPF 2- 4, (as opposed to the recommended SPF 30 and above for high protection.) This is simply not enough- for anyone.
Research suggests that while Black skin may be less prone to getting sun-induced cancer, when it does occur, the results tend to be more fatal, with higher morbidity. So, we definitely need to watch out for that.
Also, increased melanin production makes darker skin tones more prone to post-inflammatory hyperpigmentation, and lighter, with post-inflammatory erythema. Both can be difficult to deal with.
Hence, you need to protect your skin cells, including the melanocytes, from the harmful effects of sun exposure. Wearing sunscreen is one of the best ways to do so.
So, does Black crack?
While Black people/ darker skin tones have better protection from the harmful effects of the sun’s rays, they don’t have absolute protection.
Why take 10 drops of water when you can get the whole glass?
This infographic will tell you more about sun protection.
Melanin is helpful to all of us, but we can make it work more in our favour by being a bit more conscious about our sun exposure and protection.
How about you? What do you think?
REFERENCES:
Chien, A. L., Suh, J., Cesar, S., Fischer, A. H., Cheng, N., Poon, F., Rainer, B., Leung, S., Martin, J., Okoye, G. A., & Kang, S. (2016). Pigmentation in African American skin decreases with skin aging. Journal of the American Academy of Dermatology, 75(4), 782–787. https://doi.org/10.1016/j.jaad.2016.05.007
Fenelon A. (2013). An examination of black/white differences in the rate of age-related mortality increase. Demographic research, 29, 441–472. https://doi.org/10.4054/DemRes.2013.29.17
Weuve, J., Barnes, L. L., Mendes de Leon, C. F., Rajan, K. B., Beck, T., Aggarwal, N. T., Hebert, L. E., Bennett, D. A., Wilson, R. S., & Evans, D. A. (2018). Cognitive Aging in Black and White Americans: Cognition, Cognitive Decline, and Incidence of Alzheimer Disease Dementia. Epidemiology (Cambridge, Mass.), 29(1), 151–159. https://doi.org/10.1097/EDE.0000000000000747
Vashi, N. A., de Castro Maymone, M. B., & Kundu, R. V. (2016). Aging Differences in Ethnic Skin. The Journal of clinical and aesthetic dermatology, 9(1), 31–38.
Brenner, M., & Hearing, V. J. (2008). The protective role of melanin against UV damage in human skin. Photochemistry and photobiology, 84(3), 539–549. https://doi.org/10.1111/j.1751-1097.2007.00226.x
Sweta Rajan-Rankin, Race, embodiment and later life: Re-animating aging bodies of color, Journal of Aging Studies, Volume 45, 2018, Pages 32-38, ISSN 0890-4065, https://doi.org/10.1016/j.jaging.2018.01.005 (https://www.sciencedirect.com/science/article/pii/S089040651830015X)
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