How long can you keep that bottle of suntan cream? What are the signs that it’s gone off? Get Dr Hilary’s advice…

Over the last few years there has been huge confusion about sun cream.

In an effort to clarify things, the EU have ordered sun cream manufacturers to add a ‘period after opening symbol’ on the back of bottles. This is usually a little jar with the lid off and a number next to it. Like a use by date, this is a guideline on how much a sun cream can be used. So if it says 12 m (12 months), it will be fine for 12 months after opening.

Keep sun lotion in a shady and cool place when not in use as they do not withstand extreme changes in temperature.

After sunscreens expire, the chemicals begin to degrade and separate, making them less effective. Eventually, old sunscreens will crystallize, separate, and may have a foul odour.

In terms of application, the rough rule for an average adult is that you should be using cream the size of a £2 coin to cover one arm and one leg. Over your whole body you should be looking at using a 7th of the 200 ml bottle across your whole body on each application.