I have a whole routine with sunscreen products. I am fair so I burn easily and I am very aware of this when in Jamaica. I start my trip using 50SPF on my my body, 70SPF on my face. The middle of my trip I come down to 30SPF on my body and 50SPF on my face. Towards the end of my trip I go down to 15SPF, sticking with 50 on my face.
I try to stay out of the sun between Noon and 2:00pm.
Aside from sunburn skin cancer should be a real concern.
I get a killer and long standing tan. I never burn and have very minimal sun damage to my skin (and I've been a beach bunny my entire life)
I'm still tan and I've been back since February.