When exposed to the sun, why does your skin darken but your hair lighten?

In summary, when skin is exposed to sunlight, it becomes darker to absorb some of the energy and avoid burns. However, hair becomes blonde because the UV light breaks down the pigment in the hair and since hair is dead, no new pigment can be made. This does not mean the hair will turn white, as blonde hair still has some pigment left. In terms of hair color with the strongest pigment, ginger hair has the strongest pigment, followed by black hair.
  • #1
wasteofo2
478
2
I know that when your skin is exposed to a lot of sunlight it turns darker in order to try to absorb some of the light's energy, which can help avoid burns, but why does your hair become blonde?
 
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  • #2
Because the pigment in the hair breaks down under influence of the UV light, and since hair is dead no new pigment can be made.
 
  • #3
Monique said:
Because the pigment in the hair breaks down under influence of the UV light, and since hair is dead no new pigment can be made.
doesnt this mean the hair should turn to white and not blonde?
 
  • #4
White is the complete lack of pigment, blonde hair has very light pigment, the UV rays aren't strong enough to completely degrade all the pigment, so the hair will just become lighter than it originally was.
 
  • #5
so (a little bit offtopic) which hair has the strongest pigment: black or ginger?

i go for ginger :surprise:
 
  • #6
it's ironic too because this tan look with sun kissed highlights is a look most women (and some men too) strive for, thus keeping the tanning salons and hair salons in business...
 

1. Why does our skin darken when exposed to the sun?

When our skin is exposed to the sun, it triggers a process called melanogenesis. This is when our skin produces more melanin, which is a natural pigment that gives our skin its color. The increase in melanin production is the body's way of protecting itself from the sun's UV rays. The more melanin we have, the darker our skin appears.

2. How does the sun affect our hair color?

Unlike our skin, our hair does not have the ability to produce melanin in response to sun exposure. Instead, the sun's UV rays break down the melanin that is already present in our hair, causing it to appear lighter or even bleached. This is why many people experience lighter hair color in the summer months.

3. Is the amount of melanin in our skin and hair determined by genetics?

Yes, the amount of melanin in our skin and hair is determined by genetics. People with darker skin and hair have more melanin-producing cells, while those with lighter skin and hair have fewer of these cells. This is why some people naturally tan more easily than others.

4. Does using sunscreen prevent our skin from darkening?

Yes, using sunscreen can help prevent our skin from darkening when exposed to the sun. Sunscreen works by blocking the sun's UV rays from reaching our skin and triggering the production of melanin. This is why it is important to always wear sunscreen when spending time in the sun.

5. Can our skin and hair darken and lighten at different rates?

Yes, our skin and hair can darken and lighten at different rates. This is because our skin and hair have different levels of melanin and are affected differently by the sun's UV rays. Additionally, factors such as hair color treatments and skin care products can also impact the rate at which our skin and hair darken and lighten.

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