Why Do Some People Sunburn Before They Tan?

Whenever summer rolls around, people either get excited to spend more time in the Sun, or they get super annoyed because they’re going to have to hide from the Sun. Which camp you fall in probably has something to do with whether or not you tan or just get sunburns the second it gets a little warm out. If you’re in the latter camp, you might be wondering why you turn into a tomato instead of tanning. So why do some people sunburn well before they tan?

Wear sunscreen

By this point we all know that the Sun is constantly bathing us with ultraviolet radiation. This is, to put it lightly, a very good way to give yourself skin cancer. Solar ultraviolet radiation comes in three forms; UVA, UVB, and UVC. UVA is a slightly longer wavelength form of ultraviolet radiation, while UVB is shorter. Over 95% of the UV radiation you get from the Sun is UVA radiation, while the remainder is UVB. The Earth’s atmosphere absorbs over 70% of all Solar ultraviolet radiation, so little to no UVC radiation ever makes it to the surface. 

So when it comes to tanning (and cancer), you’re contending with UVA and UVB radiation—both of which contribute to your risk of developing skin cancer. We’re not going to go into how cancer works here, but big picture tumors form when your cells multiply out of control and start taking resources away from the rest of your body. UVA and UVB radiation both damage the DNA inside your skin cells, which is like destroying the instruction manual for how your cells are supposed to work. In turn that increases the likelihood of your cells turning into cancer cells. 

Further Reading: Why Don’t Big Animals Get Cancer?

UVA radiation penetrates deeper into your skin, and is largely associated with skin aging. On the other hand, UVB radiation is what gives you actual sunburns (it’s also more closely associated with tanning). Neither are good for you. If you want more motivation to protect your skin, you should know that damage to your skin from UV radiation is cumulative. Even one sunburn permanently increases your risk of developing skin cancer later. 

Sidebar, tanning salons use both UVA and UVB radiation to tan you, so keep that in mind. 

It’s genetic, sorry

When your skin gets tanned, what your skin is doing is producing more melanin. Melanin is also what dictates your skin tone, specifically eumelanin. Eumelanin is the stuff that absorbs light, and it can dissipate something like 99.9% of absorbed UV radiation, which is why it’s thought that melanin is our body’s main mechanism for protection against UVA and UVB radiation.

Tanning is a result of melanogenesis, which is just the increased production of melanin in your skin. Makes sense, if you’re being bombarded with radiation, it only makes sense for your body to make more of the thing that helps protect itself.

This might leave you wondering why your friends get a protective tan, and you just burn up. Just make more melanin, right? 

Unfortunately, the maximum amount of eumelanin you can produce is largely fixed, which the FDA has split into six skin types. If your exposure outpaces the amount of eumelanin your body can produce, you burn instead of tanning. So it turns out this is really one of those cases where some of us are just built different. 

However, this does not make those with darker skin tones functionally immune to skin cancer. While a higher eumelanin count does reduce one’s likelihood of developing a sunburn (and skin cancer), that actually makes severe health complications due to skin cancer more likely. People of color are more likely to die from skin cancer, largely in part due to the delay in presentation. For people of color skin cancer is often diagnosed in much more advanced stages. 

Also, in case you were wondering, there have been studies into the relationship between skin cancer and climate change. The relationship between the two is largely circumstantial, as a causal link is pretty hard to establish. But if you’re wondering if skin cancer incidence is increasing; the answer is yes, the incidence of skin cancer in people (of all skin types) is sharply increasing. Nonmelanoma skin carcinoma rates per 100,000 people in Australia have increased from 555 per 100,000 in 1985 to 2,448 per 100,000 in 2011. Which is, you know, like a fourfold increase in 26 years. Yes, medical journals have been screaming about it for a long time. 


Speaking of tans, see if you know your celebrities-who-made-bad-tanning-decisions here.

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