Three burning sunscreen questions answered

Which agent protects best? And what should you pay attention to if you want to buy sunscreen? KIJK answered your questions.

1) What is the best sunscreen to use?

You may now think of pretty wiedes. The higher the factor, the better the protection. But this is not so bad. “Sunscreen can act as a kind of mirror, but it can also absorb harmful radiation that can cause skin cancer,” explains Linda Sumner, spokeswoman for the Dutch Cancer Society. “Factor 30 blocks about 97 percent of harmful UV rays, while Factor 50 provides about 98 percent of protection.” A higher factor therefore blocks or absorbs a bit more and thus provides longer protection. The choice seems simple. However, factor 30 is the better option for some people, and this may seem contradictory. “Both factors work very well. But if we lubricate with factor 50, we think we are well protected and therefore less likely to lubricate again,” says Sumner. Re-lubrication is very important. You lose part of your sunburn through sweat or towel friction, for example. After a couple of hours, you’ve often lost so much that you’ll have to apply a new coat no matter what. So factor 30 is good enough for most people.

>>> Also read: Why do pigs need sunscreen? <<

2) Is more expensive sunscreen always better?

Now that you know which SPF you should be looking for, the question arises: What brand should you buy? For example, is an expensive cream better? Sumner: “The price of sunscreen doesn’t matter. An inexpensive bottle provides the same protection as a more expensive bottle. Often the costs are mainly in the extras around it, like packaging, scent, or spreadability.”

It is good to pay attention to the ingredients in the cream. Many of the sunscreens we use contain ingredients that are harmful to the environment. If you’ve just put yourself in and then go swimming in the sea, you’ll be washing off a layer. You won’t notice it yourself, but marine life will suffer. The Consumers Association investigated which types of sunscreens are most harmful to the environment.

You can also find the answers above in KIJK’s Very Thick Summer Issue. In this edition we take a closer look at more summer tips.

3) How long can you keep a bottle of sunscreen?

The Dutch Cancer Society recommends that the spreadable material be discarded after a year. The website states: “Sunscreen has a limited shelf life, because the SPF decreases after opening. The cream will then protect you less. Therefore, do not store sunscreen for too long.”

Sunscreens contain what are called UV blockers, which lose their effect over time. That’s because oxygen binds to it, changing the chemical makeup of those blockers. And when the configuration changes, the functionality changes.

In the bottle, this process is relatively slow—especially if it’s still unopened—but still fast enough to buy a new bottle a year later. On your skin, where the sunscreen is exposed to oxygen, this is much faster. This is also the reason why you have to introduce yourself several times during the day in order not to burn out.

Text: Tim Thomasin, Laurian Underwater

Sources: KIJK Summer Edition 2023, KWF Cancer ControlAnd Consumers AssociationAnd Norwegian Refugee Council

Photo: Kinga Krzyminska/Getty Images