The industry guideline for water-resistant sun creams allows the SPF of a product to drop by 50% after a total of 40 minutes in water. Water-resistance testing also takes place in what is essentially a bath – using tap water. Some people worry that using sun cream might prevent them from getting enough vitamin D, but this isn’t the case unless you really overdo it. It's common for sun creams to claim to be 'water resistant', but this doesn't mean that they're waterproof.

Casting incorrect assertions in this manner is misleading and confusing to customers and we are disappointed that Which? has chosen to do this.' CalypsoConsider the time of day – If you're spending time in the sun without wearing sun cream, you should only do so before 11am or after 3pm, as the middle of the day is when you're at the greatest risk of getting burnt. Remember, sun cream is just one part of staying safe in the sun and it's also really important to encourage kids (and adults) to: Important: Read the instructions carefully before use. Apply to clean dry skin, preferably after a shower. Apply evenly and generously 15 minutes before exposure to the sun, which will allow the product to bind with the skin and form a protective film against UVA/UVB rays. When used correctly, one application is sufficient for all day protection. The regular reapplication advocated by most sunscreens protects us against this,’ he says. To apply sun cream properly you should:

Apply to all exposed areas especially those that are prone to sun radiation e.g. face, nose, receding hairline, shoulders and feet.

However, there's no agreed definition of 'reef-safe', research is still ongoing as to the impact of these chemicals, and our tests found many mineral suncreams failed to protect as claimed – so take any claims with a pinch of salt. Kids' sun cream