NYCNews.net reports that it is important to use sunscreen, as it adds an extra layer of protection from harmful UVA and UVB rays. But it is also just as important to not use sunscreen after its expiration date, as it will offer little to no defense against the adverse effects of the sun.
The SPF (sun-protection factor) is important in determining just how much protection the user gets from UVA and UVB rays. As the SPF number increases, the protection level also increases.
Different sunscreen products offer different levels of sun protection. For example, SPF 6 to 10 are considered low, while SPF 15, 20 and 25 are considered medium. SPF 30 and 50 are high and SPF 50 plus is considered very high. Since there is no product that offers 100% sun protection, it is advisable to still avoid prolonged sun exposure, even while wearing sunscreen.
Sunscreen can be used from one year to three years, depending on the product. It is therefore advised that people should not buy sunscreen products which don't have dates on them.
According to PharmacyMix Blog, expiration dates on sunscreen products are based on tests that manufacturers use to determine just how long the product retains its potency and safety.
If findings show that a sunscreen product is effective for up to 2 years, then it will be labeled as good to used 2 years after the manufacturing date. However, this doesn't automatically mean that the said sunscreen is bad or has completely lost its effectiveness the day after its expiration date. The sunscreen product could very well retain its efficacy for several years more, but there is no way to verify, if that is the case.
The effectiveness and potency of the product also depends on where it was stored before it was used again.
For example, if it was left outside the porch, then its active ingredients would have broken down because of the heat from the sun, affecting the chemical mixture of the sunscreen.
In a typical situation, if a sunscreen product doesn't have a bad smell ( a bad smell often indicates that it is not safe to use), it is probably still safe to use.
However, without the right testing equipment to run a complete and exact diagnostic test, there is no way to know if it is safe or not. In this case, some might develop allergic reactions to the expired product. It is advised to stay on the safe side and just throw the expired sunscreen product away.
