Life on earth is sustained by sunlight from the star at the centre of our solar system. That sunlight arrives in different wavelengths: x-rays, infra-red which gives us warmth, visible light and ultraviolet light. There are two types of ultraviolet: ultraviolet A and ultraviolet B. Ultraviolet A is the most damaging, and we reduce its effect by wearing appropriate clothing, whereas ultraviolet B can be damaging without melanin production in the human skin.
Melanin prevents UVB from damaging the skin to an extent whereby it could cause cancer. It also prevents DNA damage, which has a significant impact I will soon explain. Everyone with melanin should know these facts, whatever their colour since all humans have melanin.
Skin has many functions. As the body's largest organ, skin protects against germs, protects all other organs, regulates body temperature and enables touch (tactile) sensations. The skin's main layers include the epidermis, dermis and hypodermis and is prone to many problems, including skin cancer, acne, wrinkles and rashes. Melanin protects against cancer and damage. Our skin is not simple and static; it is actually dynamic and powerful.
Over 100-200 generations it can become lighter driven by multiple complex factors to maximise vitamins D production in lower UVB radiation environments. This is called depigmentation like what happened within Africa in Southern Africa around 100,000 years ago, with Europeans around 6,000 - 8,000 years ago, and Central Asians around 20,000 - 22,000 years ago.
The dark pigmentation protects from DNA damage and absorbs the right amounts of UV radiation needed by the body, as well as protects against foliate depletion. Foliate is water soluble vitamin B complex which naturally occurs in green, leafy vegetables, whole grains, and citrus fruits. Foliate is needed for normal sperm production in men. Furthermore, foliate is essential for fetal growth, organ development, and neural tube development. Foliate breaks down in high intense UVR. Dark-skinned women suffer the lowest level of neural tube defects.
Our skin pigmentation isn’t a race. It is a God given feature of the human body, that protected the very first ancestors of the human race from the negative effects of the suns rays. The bodies of humanity’s earliest ancestors had the ability to develop multiple shades, and light skin developed before the first emergence of humans with a “white skin”.
Different skin tones of skin pigmentation is a result of adaptation to different environments and levels of UV radiation.
While melanin provides protection against UV radiation, it doesn't make individuals immune to the harmful effects of the sun. All individuals, regardless of their skin tone, should take precautions when exposed to strong sunlight, such as using sunscreen, wearing protective clothing, and taking measures to avoid overexposure.
During the summer, Europeans and North Americans have to wear sun screen and hats more often than Africans would think to use them. Africans also benefit from using sunscreen and hats, but in the absence of these inventions, melanin did the job for hundreds of thousands of years of human existence.
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