Introduction to Sunscreen Protection
Sunscreen that offers protection all day sounds ideal, but it’s not feasible in practice. Claims of "all-day protection" are no longer permitted in Europe due to the decrease in protection caused by friction and sweat. Additionally, some products offer less protection against UV-A radiation, which is crucial for preventing skin aging and long-term damage.
Effectiveness of Sunscreen Throughout the Day
A study conducted in Asia examined how long sunscreen stays on when individuals are indoors. Participants applied sunscreen with a fluorescent dye in the morning, and UV photos were taken several times a day. The results showed that after two hours, 16% of the cream had disappeared, and after eight hours, it was about 30%. Although this may not seem significant, it’s uncertain whether the sunscreen remains effective.
Applying Sunscreen Indoors and Reapplication
If you apply enough sunscreen in the morning and work indoors, reapplying it during a short walk at lunch may not be necessary. However, if you spend more time outside, reapplication is required to maintain adequate protection.
Sunscreen Forms: Stick, Spray, or Cream
Sunscreen sticks and sprays are popular due to their ease of application. However, there are concerns regarding their level of protection. Testing with a UV camera revealed that sticks often contain wax-like ingredients that stay in place and are useful for applying around the eyes, but can be more difficult to apply. Sprays are quick and easy to use, but it’s challenging to determine if enough has been applied, and they require spreading to achieve the same coverage. As a result, the promised SPF may not always be reached with these products.
Effective Sunscreen Use
In summary, sunscreen only works well if used correctly. It’s essential to apply sufficient amounts, reapply regularly, and be aware of misleading claims such as "all-day protection" or "waterproof." These claims can create a false sense of security that is not always justified. Proper use of sunscreen is crucial to ensure adequate protection against the sun’s harmful rays.
