Brian Littrell has had a number of cancerous spots removed from his body.
The Backstreet Boys star revealed that he would advise his younger self to take more care when out in the sun after suffering "several" health skills.
Speaking to Allure magazine, he said: "If I could give my younger self beauty advice, it would be to sunscreen up. I've actually had several cancerous spots removed from my body."
The 46-year-old star – who was joined in the 'I Want It That Way' hitmakers by Nick Carter, Howie Dorough, AJ McLean and Kevin Richardson - also revealed that he uses a number of beauty products as he grows older.
Brian explained: "I like Aveeno lotion because the skin on my face is tough, but it can also get irritated at times. I use Olaplex on my hair. I got into that seven or eight months ago, and I've already got hair in places that I didn't have hair, which I think is exceptional.
Howie also stressed the importance of taking care of his skin.
He said: "At this point, we're not 20 years old. Every so often I get a HydraFacial, use moisturiser, and use sunscreen. We are like wine: We're getting better with time, but you've got to massage those grapes and keep them good and juicy and plump."
Meanwhile, McLean revealed that he struggled to cope with losing his hair.
The 43-year-old singer said: "Losing my hair is something that I have personally struggled with for a long time. I ended up going to the straight Pitbull look where it's just bald, and since then I've had hair surgery.
"I did it right before I got married, which will have been 10 years ago in December. I'm going back under the knife again this year."