I didn't put skin cancer on the same level as things like pancreatic or lung cancer. Even Seinfeld made fun of it.
It took me a long time to come around to her regular use of sunscreen; it really didn't sink in until I sat in a waiting room for a dermatologist who specialized in treating skin cancer. It kills almost 10,000 people per year -- less than the 30,000 who die from prostate or the 40,000 from breast cancer, but much more easily avoidable through a couple of simple steps.
Why should we as runners care? Marathon runners are far more vulnerable to skin cancer than control groups who don't run. And there's gear for this, which is why I'm writing about it on this very sunny, very runnable day.
I used to use a visor when I was in direct sun, along with UV protective sun glasses (not religiously, but regularly). But as I'm getting older, I can see where damage from sun exposure during outdoors activity is occurring - in spots not shaded by the glasses/hat.
I've started to wear a uv half Buff bandana to keep my head and forehead covered, and using sunscreen to cover ears, face, neck and arms. Balm to cover lips. And I wear tech shirts (not singlets) to keep my shoulders covered - a particularly vulnerable spot.
I know it seems extreme, but take a look around at races at some "older" runners who don't take precautions. This damage isn't reversible.
And it's a matter of life and death, not just vanity.
PS: While it happens to women runners, men are more vulnerable than women to skin cancer. So take some care, dudes.