How long before sun exposure should sunscreen be applied?

Applying sunscreen about 30 minutes before sun exposure is considered optimal for several reasons. This timeframe allows the active ingredients in the sunscreen to adhere to the skin properly and begin forming a protective barrier against harmful ultraviolet (UV) rays. When sunscreen is applied too close to sun exposure, there may not be sufficient time for it to absorb into the skin and provide effective protection.

Additionally, most sunscreens need time to dry and establish a film that can effectively block UV radiation. Applying it at the recommended time ensures that your skin is adequately protected before it encounters direct sunlight, thereby reducing the risk of sunburn and potential long-term skin damage.