Do 'all-day' sun creams really work? Which? investigates well-known brands with worrying results

Finding the best sun cream for you and your family can be a confusing process.

There are so many brands, factors and promises made on the bottle that it can feel overwhelming to even sift through the shelves - and that's before you've even looked at the price!

It's for this reason that many people choose an all-day product, which seems like a simple yet safe choice. However, a new report from Which? has examined the validity of these long-term options, and found that many are not actually offering the levels of protection that they claim.

Which? tested four well-known brands: Boots Soltan Once Invisible 8hr Sun Protection SPF30, Piz Buin 1 Day Long Lotion SPF30, Riemann P20 Once a Day Sun Protection SPF30, and UltraSun Family SPF30, and found that on average, the protection they offered decreased by 74% over a 6-8 hour period.

Alex Neill, from Which?, explained, 'Our testing shows that these sunscreens just don't live up to their once-a-day claims so people should reapply regularly to ensure they have protection from the sun.

'With more than 100,000 people diagnosed with skin cancer in the UK each year, some manufacturers need to do more to ensure their sunscreens live up to the claims on the packaging.'

Do you know the best and worst sun creams? You might be surprised by which ones passed and failed Which?'s testing!

Speaking to the Daily Mail, The British Association of Dermatologists added 'Over the course of a day sunscreen can be washed or wiped away, leaving our skin exposed. This is not to say that these "extended-wear" sunscreens shouldn't be used at all, rather that they should be used similarly to other sunscreens.'

However, in addition to testing the four all-day products, Which? also tested 11 regular use sun creams, and found that cheaper sun creams can offer the same level of protection as their pricier equivalents. The lowest-price product to pass the test was Lacura Suncare Moisturising Sun Spray SPF30, which costs just £2.79 per 200ml bottle at Aldi.

To ensure sun safety, Cancer Research UK recommends spending time in the shade between 11am and 3pm, covering up with a t-shirt, hat and sunglasses, and using a sunscreen with a protection level of at least SPF15 and 4 stars. Crucially, you should 'use it generously and reapply regularly'.