You're supposed to get 20 minutes of sunlight a day - but only when it's at low levels (a good rule to tell: your shadow should be longer than your height). Beyond that, you know the drill.
Wear sunscreen. Sun protection is non-negotiable - because it's the most critical factor in keeping skin healthy. It's best to make sunscreen a part of your daily regimen so you won't get unexpected exposure (or get a sunburn). Use a great moisturizer that you love that also contains an SPF 30 sunscreen and affords the protection you need. If you're going to be outside for sports, use an SPF 30 and 4-star (reapply every two hours even if it says it's waterproof). Always protect your face and backs of your hands but allow your body to be exposed to some sun for a few minutes before you add sunscreen. A little redness in the skin signifies vitamin D is being made.
Zinc oxide and titanium dioxide sunscreens protect immediately while all the rest of the sunscreens - called chemical or organic sunscreens (misnomers if we ever heard one) - take 20 minutes to absorb into your skin before protecting. So, get those few minutes of sun and then apply the zinc.
Always apply sunscreen if you're going outdoors for longer than 15 minutes (even on a cloudy day, which only stops 20 to 40 percent of UV radiation). Make sure that the protection is a broad spectrum - UVB rays cause burning, but UVA rays penetrate deeper and are just as harmful - maybe even worse. UVA sunscreens are harder to find - zinc oxide and titanium dioxide work the best - and newer versions of these sunscreens form a small film rather than make you look like you smeared crayon all over your face. You need to slather all sunscreens on thick and apply them evenly, making sure not to miss any spots such as the back of the neck, the top of the ears, and any exposed scalp. Most of us don't put on enough sunscreen, and if that's the case with you, then you're only getting half the effectiveness (if you're putting on SPF 30, it's more like SPF 15). You really need one to two ounces of sunscreen to cover your whole body. This should be reapplied every two hours or after getting wet.
Ones that are hypoallergenic and non-comedogenic do not cause other skin damage. But all creams can cause pimples and rashes, so be careful. Also it should be water resistant so it doesn't end up in your eyes. Water resistant also means it will stay on your body past the first droplet of sweat when you are hot. But even then, reapply it after swimming.
More Answers from Michael Roizen, MD