Can I reuse sunscreen from one year to the next?

**Joseph Chance** (0:04)
Can I reuse sunscreen from one year to the next?
Thanks for asking.
Sunscreen is essential when on holiday, and in the summer in general, but it doesn't come cheap, and often the contents aren't fully used by the time your holiday is over. It's tempting to reuse bottles from one year to the next, to save money and reduce waste. What many people don't know though is whether sunscreen remains effective once it's been opened, or whether using an out of date product is dangerous. Let's go back to basics. To protect yourself from the sun's UV rays, there are four levels of protection. The higher a product's index, the more rays are blocked by the product. Remember that protection is important to prevent sunburn and reduce the risk of skin cancer. According to the International Agency for Research on Cancer, over 80% of skin cancer cases are attributed to excessive sun exposure.
How can I tell if my sunscreen has expired? Like any cosmetic product, sunscreen has a shelf life that indicates how long it will remain effective and safe to use. Most of the time, this is indicated on the bottle. But if it isn't, you can assume the product is good for three years from the date of purchase. You may want to write that date on the bottle with a marker so you don't forget. However, you should also look for any signs of deterioration, such as changes in color, texture, smell or consistency. If your suncream or oil looks or smells different to when you bought it, it's probably best to toss it and get a new one. You can put a little product in the palm of your hand to check if it smells bad or if the liquid is lumpy. Also look out for a greasy texture on the surface of the tube or the color turning greenish or yellowish. What are the risks of using out of date sunscreen? Using expired sunscreen can cause skin irritation or even allergic reactions. If in doubt, test it on the inside of your elbow. If any redness, tingling, patches or bumps appear after about 10 minutes, then get rid of it. Another risk is that it won't protect you effectively from the sun. According to nivea.co.uk, this is because the active ingredients that protect you from the sun begin to decompose and become inactive. What steps should I take to stay safe? To maximize your sunscreen's shelf life, store it in a cool dry place away from direct sunlight. Avoid exposing it to extreme temperatures too, so don't leave it in a hot car for example.
Always check the expiration date and keep an eye out for any changes in its appearance or smell. If in doubt, it's best to throw it out. Moreover, adopting sun safe habits like seeking shade during peak sun hours, wearing a hat and protective clothing and using broad spectrum sunscreen with a high SPF can further safeguard your skin from the sun's harmful effects. There you have it.
Now you know whether you can reuse sunscreen from one year to the next. In under three minutes, we answer your questions and help you understand the true meaning behind the trends, concepts, acronyms that are making headlines. Listen along and you will really know for sure.