Ah, the joys of summer: no school, getting ­together with friends, the familiar jingle of the ice cream truck, and long days in the warm sun. But those golden sunbeams are doing more damage than you think. UV rays can cause melanoma, a type of skin cancer that is more severe than squamous cell or basal cell skin cancer. Sadly, it is not uncommon. More than 50,000 people in the United States are diagnosed with melanoma each year. Fortunately, if you take the right pre­cautions, you can avoid this ugly disease altogether.

Melanoma can occur when the skin is exposed to too much UV light. The light causes melanocytes (a type of skin cell) to mutate and create an excess amount of melanin (the chemical that gives skin its color). This is why you appear tan after a day at the beach. Unfortunately, these abnormal melanocytes are also likely to be cancerous, so every time you go out in the sun without sufficient protection, you are putting yourself at risk.

Anyone can get melanoma, though some people are at greater risk. If you have fair skin and light eyes, a family history of melanoma, experienced ­severe sunburns as a teen, or had melanoma in the past, you are especially likely to be diagnosed with it. Many people fall into at least one of these categories, but they still put themselves at risk. Some use tanning salons, thinking that this is safer than being exposed to the sun. Not so, according to Dr. David Leffell, a professor at Yale University who specializes in dermatology and is author of the book Total Skin. He believes that tanning salons “should absolutely be avoided,” and considers them “dangerous for young people because they can get excessive UV exposure.”

You can prevent this from happening to you. The best way to avoid melanoma is to reduce the amount of time you spend in the sun. This is especially important between 10 a.m. and 4 p.m., when the sun is most powerful. Going out cannot be completely avoided, though, so when you are outside, make sure you wear plenty of sunscreen, even if it’s just for 20 minutes. “Look for labels that say SPF 30 and ‘broad spectrum,’” advises Dr. Leffell. Broad spectrum means that the sunscreen protects against UVA waves as well as the more common UVB, both of which contribute to skin cancer. Reapply the sunscreen throughout the day, every two to three hours, as well as right after you swim, since no sunscreen is waterproof, just water-resistant. This might sound like a hassle, but it’s a small price to pay to keep your skin healthy and cancer-free.

If you are diagnosed with melanoma, you need to get treatment right away. Melanoma in its early stages can be treated with surgery alone, depending on the age and health of the patient. But, if the ­condition goes untreated, it “can be very severe and even deadly,” warns Dr. Leffell. Once melanoma spreads beyond the skin to other organs (such as the lungs or liver), it becomes much more lethal.

Don’t let melanoma happen to you. Why would you, when it is so easily preventable? By taking ­precautions now, during the first 18 years of your life, you can reduce your risk of skin cancer by 78 percent. Perhaps Danielle, an eighth-grader whose grandfather died from melanoma, put it best: “While it’s ‘totally hot’ to have that olive skin tone, is it ­really worth it?”