What we’re all doing wrong with our sunscreen

As the heat melts the asphalt, the beaches fill with young and old seeking a breath of coolness, dipping in and out of the water. But where do you leave your sunscreen all day?

Chances are you leave it covered with your towel, thrown on the sand, or inside your car. However, whichever of the three you choose, it’s not a good idea at all, because sunscreens degrade when exposed directly to the sun or left for hours in the heat, explains dermatologist and venereologist Dr. Markos Michelakis, from EDOEAP.

“Excessive heat can break down their filters, reducing the protection they provide against the sun’s ultraviolet (UV) radiation,” he explains. “This is why the relevant authorities, like the FDA, recommend not leaving them exposed to the sun at all. It’s preferable to wrap them in a towel and place them in a shaded area. However, this place should never, under any circumstances, be the car, because when it’s hot, it turns into a real oven.”

However, if you plan to spend many hours at the beach, “store your sunscreen in a portable cooler, which is cooler,” he continues. “Don’t forget that their packaging states they must be protected from extreme heat.”

Storing sunscreen in conditions that promote its degradation is not the only mistake we make. The FDA recommends paying special attention to the timing of application and the areas of the body that are often forgotten.

A study by the University of Minnesota a few years ago showed that only one in three people applies sunscreen to all exposed areas of the body. “The hairline on the face, the neck, the ears, and areas of the scalp with thinning or no hair are the spots most people forget,” says Dr. Michelakis.

Other areas often left unprotected in the sun are the tops of the feet, the nose, the lips, and the tops of the hands.

Overall, only four in ten people have a separate sunscreen for the face, which they apply correctly and consistently. Additionally, less than 4% remember to apply it to their feet in areas not covered by sandals or flip-flops. And only 6% remember to apply sunscreen to all exposed parts of the chest.

Equally concerning is the fact that 65% of adults forget to reapply, as shown in a study by the American Academy of Dermatology (AAD). However, sunscreens do not last more than two hours of continuous sun exposure. There are also no waterproof sunscreens that maintain protection if you sweat heavily or swim in the sea. Sooner or later, protection will be lost, and you will be exposed to UV.

Unfortunately, only one in three consistently re-applies every two hours when dry (or more frequently if wet). Especially in the city, most people apply sunscreen only once in the morning, unless they plan to go swimming.

Moreover, most people only use sunscreen when it’s sunny. On cloudy days, only 20% apply sunscreen, even though up to 80% of UV penetrates clouds and reaches our skin.

It is very important not to apply sunscreen at the last minute before going out in the sun. It takes at least 30 minutes to take effect, especially if it contains chemical filters (physical filters act faster). You must also apply enough to cover the exposed areas of your face and body thoroughly. Unfortunately, most people use only 25-50% of the amount actually needed. For the average adult, this amount is about 30 ml (almost a shot glass) to cover all exposed areas of the body.

You should also gently rub the sunscreen into your skin until it is fully absorbed. Then the filters will activate.

For even greater protection, your sunscreen must meet certain specifications. First, it must not be old. If you don’t remember when you bought it, throw it away. Sunscreens last up to three years if not exposed to sunlight or intense heat.

Second, sunscreen should be broad-spectrum, protecting against both UVA and UVB radiation. UVB mainly causes sunburn and, in the long term, skin cancer. UVA penetrates deeper into the skin, accelerates skin aging, and also contributes to cancer over time.

Your sunscreen should also be water-resistant (it will say “water resistant”) and have a sun protection factor (SPF) of at least 30. If your skin tans, do not switch to a lower SPF sunscreen. It’s a myth that tanning makes your skin more “resistant” to UV. On the contrary, it indicates that your skin has been damaged by the sun, and the more you continue exposing it to UV, the more damage you accumulate.

Finally, remember that sunscreen alone is not enough to adequately protect your face. You also need a wide-brimmed hat, because most cosmetic products (e.g., moisturizers, makeup) with SPF protect against UVB, not UVA. Therefore, it’s a good idea to wear a hat going forward, concludes Dr. Michelakis.