- Black skin has a natural sun protection barrier equal to sunscreen of 13.4 because it contains more melanin (the stuff that gives your skin its colour). White skin has only a quarter of that protection against the rays of the sun. Its protective barrier amounts to an SPF of 3.3.
- This advantage means Black skin shows signs of sun damage more slowly, but more melanin also means there’s a higher chance of developing uneven spots that may be darker or lighter than the skin around it.
- Collagen is the protein that causes Black skin to age slower. But, lots of collagen leads to more opportunity for scars to form. This extract from United Kingdom doctor Dija Ayodele’s book “Black Skin” explains how this works and why there’s insufficient research into effective treatments.
One of the most popular questions I get asked is, ‘Is skin not just skin? Bar colour, is it that different?’
There are similarities, but Black skin is physiologically different to white skin in a few ways.
There are also cultural differences in the way we treat the skin.
Melanin and the anatomy of skin
The differences in our skin colours are down to our genetic backgrounds, location, and our individual environmental exposure to the sun.
Those closer to the Equator generally have Black or darker skin tones to protect against the high ultraviolet (UV) exposure that comes from the sun. Ultraviolet rays are harmful, invisible sun light that cause damage to your skin and can lead to cancer.
White skin is predominantly found in the northern part of the Globe and tends to be lighter to enable it to absorb vitamin D from the sun.
However, global travel has moved us all over the world, so these are not hard and fast rules.
Everyone – be you of Black, white or mixed-race heritage – has melanocyte cells, living in the very bottom layer of your skin called the stratum basale.
Within these melanocyte cells are the melanosomes, the bits that contain the pigment called melanin.
In the bottom layer of your skin, the cells that contain melanin are actually transparent with no colour at all. As they migrate through the layers of skin, they then take on their distinctive colour.
There are two different types of melanin pigment produced by the melanocytes: eumelanin – a dark brown pigment, and pheomelanin – a red or yellow tint.
Black people and those with darker skin tones have more eumelanin, hence our different shades of brown skin colour, whereas white and lighter skin tones have pheomelanin.
The melanocyte cells have tentacles, just like an octopus, that extend to other layers of skin to make sure melanin pigment is evenly distributed throughout the skin, giving us all our unique individual skin colours.
The key factor when it comes to skin colour is the size and the number of melanocytes and melanosomes.
Black and darker skin tones have larger individual melanin carrying cells that are evenly distributed through the epidermis.
In Black skin, melanosomes are also more active and produce more melanin.
In fact, some studies have shown that Black skin produces twice as much melanin as white skin.
These cells that house the melanin also age more slowly in darker skin tones.
White and lighter skin tones, conversely, have smaller melanosomes, which are clustered together and rarely found in the upper layers of the epidermis.
The melanosomes in white skin are stimulated by UV radiation from the sun, hence why white skin goes brown in the sun.
In the middle of this spectrum sits people of Asian descent, who also have large melanosomes that are found individually as well as grouped together.
Together, the combination of increased melanin and its distribution in the skin gives Black skin some protection from premature ageing caused by UV radiation from the sun.
On average, research points to Black skin having an approximate natural sun protection factor (SPF) of 13.4.
White skin sits somewhere around 3.3.
But before you run amok with no sunscreen, remember that the increased melanin levels in Black skin also make it more likely to change colour, whether it happens through loss of colour (hypopigmentation) or patchy, uneven deposits of colour (hyperpigmentation).
Why your skin can feel dry
Another difference between Black and white skin is how quickly water is lost through the skin.
One of the functions of the skin is to provide a barrier against water loss and to help the skin stay hydrated. Anything that disrupts the skin’s delicate barrier can cause increased water loss, which we in the business refer to as the “transepidermal water loss” or TEWL.
A significant number of studies show that whilst Black skin has on average more of the oily substance that lubricates and protects the skin. It also has a thicker top layer than white skin, but Black skin has fewer of the cells that preserve moisture in your skin so it is prone to increased water loss.
This contributes to increased dryness of the skin and the increased likelihood of us experiencing dry, flaky and ashy skin conditions.
I tend to find most women, even if they usually have an oily skin type, will complain of drier skin in the winter months. This is because cold weather and winter wind whips moisture away from the skin and, combined with warm homes, your skin will feel parched and dehydrated, easily losing its glow and vitality.
Ever get that dry, itchy feeling on your pins after removing your tights? That is TEWL in action.
Too much collagen, not enough research: Why treating scars isn’t straightforward
They say too much of a good thing isn’t good for you, and that can be the case with collagen.
Black skin is more prone to what’s known as “hypertrophic” and “keloid” scarring, both caused by the overproduction of collagen after injury.
White skin can also get keloid scarring, but it has been noted to be more common in Black skin.
A regular scar will heal at the site of the injury; these scars will not be elevated or abnormal.
Hypertrophic scars will heal at the site of the injury but may be raised, although there is a chance that they could spontaneously turn back into a normal scar.
Keloid scars, on the other hand, are larger than the point of the original injury.
They can be hard, raised, shiny, hairless and smooth; they are also often uncomfortable, unsightly, itchy and painful, depending on their location.
Currently treatment options are basic, ineffective, and produce inconsistent results. They vary from topical and injectable steroids to hydrogel compression sheeting, all designed to stunt the overdevelopment of collagen.
Surgery is also an option, but there is always the risk that the keloid will return bigger and badder than before. See why there needs to be more research?
Why Black skin looks younger for longer
The statement “Black don’t crack” is often used as a compliment because Black women tend to have a later onset of fine lines and wrinkles compared to white women of a comparable age.
There is a reason for this and it’s all to do with collagen and the effect of UVA rays on the skin. Collagen is the protein that makes skin look plump.
Black skin has thicker, tighter and smaller collagen fibres, formed into bundles, and melanin acts like an overcoat protecting these bundles from the damage that UV rays cause when it penetrates the skin.
So they stay intact for longer, firmly propping up skin. In comparison, collagen in white skin is much more susceptible to UV damage due to the lack of readily available protective melanin.
The collagen construction in white skin is under much more stress and strain from extrinsic ageing factors because it is not as robust.
Whilst skin may be “just skin”, understanding the differences between Black and white skin is crucial in knowing how best to look after yours, as we’ll explore further in the book.
This extract from the book “Black Skin” was provided by Jonathan Ball Publishers.