A new study says that it only takes five serious sunburns between the ages of 15 and 20 to increase your risk of melanoma by 80 percent. Unfortunately, that means it’s relatively easy to develop the most deadly form of sun cancer. The U.S. study, which followed more than 100,000 Caucasian women for about 20 years, also found that increased exposure to UV rays (either from the sun or a tanning bed) in adulthood was associated with a greater risk of non-melanoma skin cancer. It’s troubling to think that some of the most dangerous sun damage is done before we're old enough to make smart decisions. After all, if you think back on your teenage years, chances are that you had a few sun indiscretions. And you aren’t alone. About a quarter of the women in the study admitted to having sunburns that actually blistered when they were young. What can you do when the damage is done? So now that you know the potential effects of your youthful mistakes, what is there left to do to protect yourself? Well, when it comes to a disease like melanoma, it’s important to catch any problems early, so it’s a good idea to screen yourself for irregular moles. Use a full-length mirror to fully inspect your skin (don’t forget hidden places, like between your toes!) for new moles or moles that have changed. You should be wary of moles that exhibit any of the following troubling qualities (known as ABCDE): - Asymmetrical shape - Irregular border edges - Different colours - Diameter larger than a pencil - Evolving colour, size or shape Try to repeat this process once a month to keep on top of any new concerns. Get a mole-tracking app to make sure you pick up on any changes, and visit your dermatologist if you ever have concerns. While most moles are benign, it’s better to be safe than sorry. And remember: You still need to protect yourself. Though early-life sun exposure might be the worst kind for melanoma risk, other skin cancers are related to exposure throughout life, and cumulative exposure is also an important factor for cancer risk. If you’re a parent, this study is also a very important reminder to keep your child protected from the sun at all times, using sun-protective clothing and a good sunscreen. Encourage your teens to opt for sunless tanning lotions and make sure they have a good SPF on hand when they leave the house. Learn more about protecting yourself from skin cancer and learn how to choose a healthy sunscreen for your skin. (Photography: Thinkstock)