Sunscreen is an important part of good sun protection. In addition to other measures, such as wearing sunglasses or avoiding direct sun around midday, sunscreen helps in situations in which you cannot or do not want to avoid high UV exposure. We have gathered a lot of information which you can find in the articles linked below.
Applying sunscreen means that fewer UV rays reach the skin. How much of it still gets through depends on the sun protection factor (LSF or English SPF). Together with the skin's own protection time, which is determined with the help of the skin type, it can then be roughly predicted how long it will take for a person to burn themselves at a certain UV index. However, it should also be noted that frequent use of sunscreen can lead to a vitamin D deficiency and that certain ingredients in sunscreen are controversial. This applies to both of the main types of sunscreen.
Correct application of sunscreen
- Chemical sunscreens (i.e. with organic filters) only take effect approx. 20 minutes after application and should therefore be applied before exposure.
- The specified sun protection factor of sun creams is based on a very large amount of sun cream per area. Most people use significantly less and therefore only have about half the advertised protection factor.
- Sunscreen is slowly removed by sweat, friction and water, thereby losing some of its protection. Depending on your activity, you should therefore reapply sunscreen after a while.
sun-a-wear can give you recommendations on when it is advisable to apply sunscreen and can give you an estimate of how long it will take for your current UV radiation to reach your UV dose limit. The app can also remind you to reapply sunscreen when the sensor detects a lot of movement or submersion in water.
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