Cosmetics: what you need to know about use by dates

First up, yes, even cosmetics have use by dates. They can go off after opening like food, and harbour nasty bacteria that you don't want anywhere near your face. Ancient makeup can cause skin irritation and infections. The next important thing to know is every makeup product should show an expiry date, displayed on the packaging. It looks like a little pot with an open lid and will have a number next to the letter 'M' which stands for months. So for example, my current fave cosmetic Dr Pawpaw Original Balm that I use for almost everything has '12M' written on the pot symbol. Phew, that's good for a few more months.

© Photo: Rex

Clearly this article had me searching through my entire makeup kit, with some surprising discoveries, many of which are now in the bin. You just assume your makeup will last for ages don't you? Wrong. My Hugo Boss Femme perfume says 36M – not as long as I'd thought - my Yves Saint Laurent eyeshadow palette expires after 24 months and my Max Factor liquid liner is only good for nine months. So it seems that expiration dates vary on different products.

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© Photo: Rex

According to Superdrug's website, mascara only lasts for up to 3 months and should definitely be replaced when it starts going clumpy and smelling. Eyeliner is only good for between six and 12 months, liquid foundation is fine for a year and powder foundation can last up to two years.

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Who's kept a lipstick for years and years? We're all guilty. Superdrug recommends two years as a maximum time for your fave lippy before replacing. Eyeshadow and blusher are also good for two years.

The real long lifers are nail polish and perfume. Nail polish can go on for longer than two years as it contains bacteria-killing solvents, while perfume expiration dates vary between three to five years. But, writes Superdrug: "When the fragrance changes in colour, particularly if it turns darker, or if it starts to smell unpleasant, it’s time to bin it."

Time for a good old sort out ladies…