How long does sunscreen last?
Yay, holidays! Pack up your suitcase with bikinis, dresses and shorts, a good book and... a tube of sunscreen you had on hand from last year. Right? Well, you don't. Sunscreen wears off fast every year, so it's best to invest in a new bottle every year. We tell you all about the shelf life of sun block in this blog.
Factor 30 will be factor 15 next year
To get straight to the point: sunscreen with SPF 30 that you bought brand new last year and used, will only be SPF 15 this year. Yep, the factor level drops by about half every year. So whereas last year you were well protected with SPF 30, this year you are not. Remember that SPF 15 is only really SPF 15 if you apply liberally (which is a lot). Hardly anyone does this - so your factor 15 is then perhaps only SPF 10 or lower (!)
12 months shelf life
But what about the icon of an open jar with the text '12M' next to it? This is the shelf life of the sunscreen itself, not the factor. The icon and the caption 12M mean that your sunscreen has a shelf life of 12 months after opening. After this period, the texture or smell of the cream may change. So, for both shelf life and factor efficacy, throw your cream away after a year anyway.
The only way to go: a new bottle of SPF
Long story short: buy a new bottle or tube of sunscreen every year. Only a brand new one will ensure the best protection from the sun.
How to store your sunscreen?
Even during the year, you want to make the most of your SPF bottle. You can do this by keeping it at room temperature. On a hot beach day, don't leave it in the open sun, but preferably drop it in the cool box (if you have one). Don't leave your tube of sun cream in the car either, it will quickly overheat there. Has the year not yet passed but you notice that your sun block is 'different' (smells, is watery)? Then throw it away and buy a new bottle.