Everything you need to know about skin cancer and how to prevent it

Summers in Georgia can be brutal. Temperatures hover in the upper 80s, and the sun shines relentlessly for days on end.

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While this is great for those warm-weather cookouts and afternoons by the pool, it's not always good for your skin – especially when it comes to skin cancer risk.

According to the Atlanta-based Centers for Disease Control and Prevention, skin cancer is the most common cancer in the United States. And most cases of the deadliest kind of skin cancer (melanoma) are caused by exposure to ultraviolet light.

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And while UV rays make up a small portion of the sun's rays, they're the main cause of sun damage on the skin.
Nationwide rates of melanoma have more than tripled since the 1970s, despite better screening methods, more public awareness, and continued advances in treatment and diagnosis.

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For every 100,000 people in the country, 21 new melanoma cases were reported from 2011-2015. Three died of cancer. In Georgia, the rate of new melanoma cases during that time range was even higher: 26.2 per 100,000 residents.

Here are some lesser-known skin cancer facts, plus tips on keeping your skin protected year-round.

Skin cancer isn't just about a bad sunburn

Many people with skin cancer were often surprised by their diagnosis, because they didn't necessarily have recent sunburns.

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But the truth is, when it comes to basal cell carcinoma and squamous cell carcinoma, the two most common types of skin cancer, cumulative sun exposure – the kind that occurs over weeks and months and years – is just as damaging to your skin.

That means a week of laying by the pool for an hour poses about the same risk as one 7-hour beach day.

A cloudy day doesn't mean you're protected

Most of us know that we need sunscreen when it's bright and sunny, but what about when it's overcast?

The Skin Cancer Foundation estimates that up to 80 percent of the sun's harmful rays reach us on cloudy days -- which means you aren't protected simply because the sun isn't out.

What's more, UVA rays -- the one's responsible for skin aging, freckling and wrinkles, can pass through car windows, office windows and other types of glass. So, just because you're indoors, doesn't necessarily mean you're protected, either.

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Skin cancer doesn't always look like a mole

There are three different types of skin cancer, and a mole is only symptomatic of one.

Basal cell carcinoma can appear as a persistent pearly, or skin-colored bump that may crust or bleed. Squamous cell carcinoma can appear as a patch of thick, scaly skin with raised edges. They may also crust or bleed, and usually won't heal or go away on their own.

Melanomas can be a mole. But they can also look like a bump or blemish that bleeds, itches or changes color, size, shape, consistency or diameter. Concerned about a mole or mark on your skin? Try the ABCDE method.

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The difference in SPF protection isn't as big as you think

Skin protection factor, or SPF, is the amount of sun required to burn the skin while wearing sunscreen. And higher isn't always better. Sometimes it can actually be worse, because many people will apply a high SPF sunscreen thinking they can stay out in the sun longer, which isn't true.

SPF 15 blocks around 94 percent of UV rays; SPF 30 blocks around 97 percent. An SPF of 50 will block about 98 percent of UV rays, while an SPF of 100 blocks 99 percent.

And none offer 100 percent protection.

To keep your skin protected: