Items all around you expire every day: the milk in your fridge, and even the products in your vanity. But the latest item to be given an expiration date is certainly the most unexpected. According to a new study from researchers at the University of São Paulo in Brazil, your sunglasses can lose their UV-blocking power over time with just everyday wear and tear. Every time you drop your sunglasses on the ground or throw them in your purse, you damage the lenses, even if you can’t actually see the micro scratches. Those vintage Ray-Bans you love so much may make you look cool, but they might be ineffective.
Don’t think this is a big deal? Exposing your eyes to UV rays can be linked to premature aging, and even worse, vision loss from cataracts or ocular cancer. The study concluded that your go-to shades should be replaced after two years (for users who wear them two hours a day, max). Our advice: Use this as motivation to splurge on a new pair every couple of years.