With high temperatures setting in across the country, many of us are heading to the pool or the beach in our spare time. If we're smart, we're piling on the sunscreen to protect our skin and prevent burning, but questions abound: Are we buying the right sunscreen? And finally (and for many, most important) why might we still get a sunburn even with sunscreen and how can we best treat this typically minor but painful skin irritation?

There are two types of sunscreen: chemical and mechanical

First, a lesson in what sunscreen actually is; there are two types: chemical and mechanical.

“Chemical sunscreens have a variety of different chemicals that actively absorb light — particularly the most damaging light, UVA and UVB [ultraviolet A and ultraviolet B] rays,” says Dr. William Wooden, a plastic surgeon specializing in skin cancer and director of operative services at Indiana University School of Medicine. "This is the light that causes a burn but also can damage your cells, predisposing you to skin cancer.”

Mechanical sunscreen, typically touted as “natural,” “has naturally occurring elements and minerals that act like mirrors and block the rays,” says Dr. Wooden. “We have identified that you can micro-powerdize minerals and titanium oxide so it doesn't make that white goo our grandfathers wore — so if you want to stay away from chemicals, you can buy these.”

That said, chemical sunscreen is safe to use. Essentially, as Dr. Wooden explains, chemical sunscreen has shown to not pose risks to one's health or secondary skin problems, and is shown to be highly effective in blocking dangerous light from the sun by absorbing it.

Which type of sunscreen is better?

What's the best choice? Dr. Wooden is agnostic on the matter, feeling that it’s up to the consumer’s preference and that everyone should stick with what their skin handles best.

While both types of sunscreen are safe for humans, Dr. Wooden points out that one type may safer than the other at least when it comes to our oceans: "Hawaii has identified that chemicals, [oxybenzone and octinoxate], which are ubiquitously common in chemical sunscreens may be damaging our coral reefs. Hawaii has banned the sunscreens with these chemicals."

If you decide to go the mineral-based or mechanical route, be sure to look for a product that has both titanium dioxide and zinc oxides, says Dr. Wooden.

SPF: 30 is the magic number

Though I’m someone who generally doesn’t burn (likely because I’m more olive in skin tone, a factor I’ll get to shortly), I still always look for the maximum protection in sunscreen and usually end up forking over extra money on the SPF 110, believing that the higher the SPF grade, the greater and longer the protection. This isn’t quite how it works.

“The difference between SPFs is real, but diminishes with increasing SPF numbers,” says Dr. S. Tyler Hollmig, dermatologist, dermatologic surgeon, and dermatologic oncologist at Stanford Health Care. “For example, an SPF of 2 would block only about 50 percent of dangerous light, while SPF 15 blocks 93 percent, SPF 30 blocks 97 percent, and SPF 70 blocks 98.5 percent. Most dermatologists agree on an SPF of 30 as sort of the magic number when it comes to sunscreen.”

There’s some argument to be made that higher SPF ratings (over 30) can be less effective than that magic SPF 30, just because people tend to use less of them and apply them less often. This is definitely the case with me. I’ll slather the SPF 30 on my body all day because it’s cheaper (and I because I’ve believed it to be less effective); meanwhile I treat my pricey SPF 110 like a precious, all-powerful potion, using only a sparing layer once a day for my face.

“Studies have shown that higher SPFs actually perform like a lower SPF when too little is applied,” says Dr. Hollmig.

Oops. Time to apply more to my face, even if use up all the expensive SPF 110.

How much to apply and when

“Sunscreens should be reapplied about every two hours regardless of their SPF rating; higher SPF sunscreens don't necessarily last longer than lower SPFs. The key is that enough sunscreen be applied (about a shot glass full is required to cover the entire body) to provide optimal protection. Otherwise, people may use a sunscreen with an SPF of 30 but only get SPF 15 (or less) protection,” says Dr. Hollmig.

You may want to reapply more frequently if you’re in the water or playing sports.

“Sunscreen rubs off with sweat and activity,” says Dr. Wooden, who adds to go in the shade and cool down while you reapply.

Additionally, you should apply the first layer of sunscreen for the day before you get in the sun so that it has time to dry and absorb.

Dr. Wooden also emphasizes to drink lots of water before and after being in the sun.

I got burned anyway! What the heck?

I noted that my skin seldom burns, but my fiancé, who’s about as pale as one can be, gets lobster-red after a day in the sun, even if he’s doused in sunscreen. Why? It comes down to the evolution of skin types. See, I inherited my mother’s olive-tinged Mexican complexion, while my fiancé, 100 percent Irish, got well, the Irish complexion.

“Certain darker skin types are more tolerating of the world. They’re not immune to cancer by any means, but their [protective] skin cells called melanocytes turn on more easily,” says Dr. Wooden. So my skin, though removed both ancestrally and geographically from Mexico, was designed, through years of evolution, to be adaptable to the balmy climate. My fiancé, on the other hand, has skin that had no reason to adapt to hot weather, and is meant to thrive in the drearier climes of Dublin or Derry, Ireland.

Fair-skinned people like him need to go “the extra step” in sun care, best achieved by wearing sun-protective clothing or just staying in the shade altogether.

To lower your odds of being burned, Dr. Joshua D. Zuckerman, a plastic surgeon, recommends looking up the UV index in your area, and staying out of the sun during high UV days. Even on low UV days you should apply sunscreen.

Treating the burn so it heals fast

If you get a sunburn, you’ll need four things to heal it quickly:

Water (to drink)

A tub or shower with cold water

An anti-inflammatory

And a topical, soothing ointment

“The key thing to recognize is that this is a superficial burn so rehydrating is important,” says Dr. Wooden. “You need to rehydrate from the inside out as well as from the outside in.”

Drink tons of water, but do it in the shade or indoors so your body can cool down.

Once home, Dr. Wooden recommends soaking in a cold tub. A cool shower should also do the trick. The point is to physically cool the skin down.

“Next is the anti-inflammatory component,” says Dr. Wooden. “An anti-inflammatory, like Motrin, can be very helpful in soothing the inflammation of a sunburn.”

Finally, you’ll want to treat the skin itself.

“Bland topical creams and ointments (a shorter ingredient list is almost always better than a long one) help reduce itch and speed healing in any areas where blisters have occurred or skin has peeled,” says Dr. Hollmig. “Topical anti-itch medications are typically best avoided, as these can sometimes cause an allergic skin reaction that increases discomfort. Any blisters should be either left intact or gently drained from the side using a sterile needle. The roof of blisters should be left in place to serve as a protective covering of the injured skin beneath.”

So, what about the shaving cream ‘hack’?

A new Buzzfeed article that went viral featured a woman who healed her sunburn by coating the affected area in menthol shaving cream and letting it sit for 30 minutes. While it may be new to many of us, Dr. Wooden laughs this off as nothing new.

“It’s not a hack; it’s been around for years and it’s how shaving cream works,” Wooden asserts. “The job of shaving cream is to hydrate, soften and moisturize.”

But does it work? It can — but it doesn't have to be your first go-to.

“I typically recommend Sarna lotion that does have menthol in it, but it also has pramoxine that numbs the burn and itch,” says Dr. Holly Gunn, assistant professor in University of Alabama at Birmingham’s Department of Dermatology. Using a creamy moisturizer with aloe vera can help too, like Jason Soothing Aloe Vera Cream. You can use any creamy moisturizer several times throughout the day to help hydrate the skin.”

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