How many years does sunscreen last

But unlike your cosmetics, sunscreen has a medical purpose: to prevent sunburns and decrease the risk of skin cancer and premature aging. So you should treat it like you do expired medication — don't use it and throw it away. So what do you do if the sunscreen doesn't have an expiration date? So if the sunscreen has no expiration date, this means it is okay to use for up to three years after being manufactured if it was made in the US. The tricky part might be remembering when you bought it.

As long as you store it inside, the sunscreen should be fine. Companies make sure the products are stable under a variety of temperatures and humidities that you might find indoors, said Feely. However, excessive heat causes sunscreen to break down faster, so try to keep it in a cool place and out of direct sunlight.

If the sunscreen has been sitting in the heat, like a hot car, Feely recommends discarding it after a few months. So the three-year mark should really be treated as an upper limit, and you're better off replacing it regularly.

I tell my patients to use sunscreens for one season and purchase a new set for next year to be safe," Zeichner said. Doctors generally recommend that you apply sunscreen on exposed skin every time you go outside in the sun all year round , which means you'll probably run out before it expires.

Most individuals use a half to a fourth of the amount of sunscreen that is advised. Y ou likely have a half-used bottle of sunscreen in the back of your medicine cabinet, and another one in the depths of a beach bag. The answer is yes, according to the Food and Drug Administration FDA — but your bottle may last longer than you think. The FDA requires all sunscreens to be marked with an expiration date, unless the product has been proven to last at least three years.

However, you should still use common sense to determine whether your sunscreen is expired, says Dr. Another way to cut down on leftover sunscreen? Use more of it. Write to Jamie Ducharme at jamie.

By Jamie Ducharme. Get our Health Newsletter. You can look to the expiration date on a bottle of sunscreen to determine how long it will last. The only exception to this is when a manufacturer has proven its product to last at least 3 years. Once sunscreen has expired, it becomes less effective at blocking UV rays, therefore increasing your risk of sunburn and skin cancer. In addition to this, exposure from direct sunlight and high temperatures can cause sunscreen to become less effective over time.

To determine whether sunscreen has gone bad or not, look to the expiration date stamped on the packaging. Be sure to discard any unused sunscreen after this date as it may no longer be effective in preventing sunburn. Another indicator is any obvious changes, such as how it smells or how it applies to your skin. If the smell or consistency is off, toss it. Lastly, use your own judgment. Keep sunscreen in good condition by storing it in a cool, dark place. Exposing the container to excessive heat or direct sun can cause its ingredients to become less effective.

When outdoors, you can protect sunscreen by wrapping the bottle in a towel or placing it in the shade. Keep the lid on firmly at all times. Another idea is to apply sunscreen indoors so you can avoid taking it out in the sun. This is especially true if the active ingredient is a physical sunblock like zinc oxide or titanium dioxide.

Physical sunblocks once had an opaque, paste-like consistency but over the past several years manufacturers have developed more cosmetically elegant formulations by micronizing the particles. She adds that micronized zinc oxide and titanium dioxide can clump together over time so the particles are coated with dimethicone or silica to keep the ingredients stable and smooth.