There are many commercially available sunscreen and other new cosmetic products containing sunscreens that are being continuously improved and developed to last longer. However, the question still arises, does sunscreen expire? Although a bottle of sunscreen usually don’t last more than a year if used properly, it is very important to check for expiration date before you purchase any sunscreen.
Most sunscreens that may or may not be labeled with expiration date have around 3 year’s shelf life. Sunscreens that expire before 3 years are usually labeled with expiration date. After its expiry date sunscreen starts to degrade and separate and is less effective. You may notice crystals or clump separated with water after your sunscreen expires. Other factors beside expiry date, like heat and excessive exposure to light radiation can also degrade the chemical in the sunscreen and as a result it looses its sun protection efficacy. For maximum result and to reduce the chances of degrading always store your sunscreen in cool place.
Experts suggest that organic sunscreen should never be kept for longer period than 18-24 months because unlike chemical sunscreen, they don’t contain synthetic preservatives that helps stabilize the ingredients for longer period. Applying expired sunscreen is not that harmful but it will have no effect on sun protection.
To get the maximum protection from the sun, always use broad-spectrum sunscreen with a sun protection factor (SPF) of at least 30 or more. Apply sunscreen 20-30 minutes prior to sun exposure and re-apply after every 2 hours. Although most of the sunscreens available commercially are advertised as water resistant or even sand resistant or rub resistant, you should always re-apply after you are exposed to water.