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Three ways sun creams are letting you down

Why ‘once-a-day’ and ‘water-resistant’ sun creams and cosmetics with an SPF might not be providing the protection you would expect

As summer temperatures continue to soar in the UK and Europe, picking a sun cream that will allow you to safely enjoy your time outdoors is more important than ever.

But our research has found that it’s not as simple as deciding which SPF to go for. Over years of testing, we’ve found sun creams that have failed our SPF tests, plus equally worrying issues with ‘once-a-day’ and ‘water-resistant’ sun creams.

Fortunately, we’ve also found several sun creams that not only provide protection from UV radiation from the sun – they’re pleasant to apply, too. Head straight to our Best Buy sun creams page to find out which sun creams will keep you protected without leaving your skin feeling sticky or greasy.

Water-resistant sun creams warning

Some 95% of the sun creams we’ve tested claim to be water resistant. But you may be surprised to learn that the industry guideline for water-resistant sun creams allows the SPF of the product to drop by up to 50% after 40 minutes in tap water.

We decided to do a more realistic test – we tested two popular products in chlorinated water (to mimic a pool), salt water (such as the sea) and fast-moving tap water. Most of the time the sun creams weren’t as effective in our more realistic conditions as they were in tap water – in salt water, one sun cream’s SPF plummeted by 59%.

You may already be surprised that you could buy an SPF30 sunscreen that drops to SPF15 after 40 minutes in tap water, and that would be considered water resistant. But our results suggest the product’s SPF would fall even further if you went into the sea, moving water or chlorinated water. In reality, there’s just no way to know what SPF you’ll be left with after going into the sea or pool by looking at the label.

In Australia and the US, the labelled SPF of a sunscreen must be the protection it provides after immersion in tap water – not before. We’d like to see the rules change here, too. In the meantime, make sure you pick an effective product from our sun cream reviews and apply it generously before swimming and again when you leave the water.

Once a day: stay away

There’s no denying that the thought of only needing to apply sun cream once a day is appealing. While manufacturers tell us they do a range of their own tests on once-a-day sun creams, there’s no industry-wide standard approach they all have to use to prove once-a-day sun creams provide the level of protection claimed, all day.

We conducted our own tests on four popular once-a-day products that claimed to protect you for between six and eight hours. We saw an average 74% decrease in SPF protection over this time. That would see an SPF30 product drop down to an SPF8.

‘Once a day’ isn’t allowed on sun creams in Australia, where any claim that leads consumers to believe that their sun cream doesn’t need to be regularly reapplied is forbidden.

We don’t think you can rely on any sun cream to keep you protected in the sun all day. You’ll need to reapply once-a-day sun creams regularly, just as you should with any other product. Read more about the tests we conducted looking into once-a-day sun creams.

Cosmetic SPF claims

Do you rely on a moisturiser or foundation to help keep you protected in the sun? It’s common for cosmetic products to make SPF claims, but no product can offer full protection if the right amount isn’t applied.

For any product to provide the SPF it claims, you need to apply 2mg per cm² – that means around a teaspoon of product needs to be applied to your face. In reality, it’s very unlikely you’re applying enough foundation for it to protect you from the sun – plus you’ll need to regularly reapply it throughout a day. A 30ml bottle of foundation would disappear after as few as six applications.

When used realistically, make-up simply isn’t going to protect you from the sun on its own, so we don’t think manufacturers should be making these SPF claims. If you’re going out in the sun, you’ll need to wear sun cream.

How to stay sun smart

Sun cream is an important part of staying safe in hot weather – but no sunscreen can provide 100% protection. Make sure you’re as sun smart as possible, by following these tips:

  • Apply enough sun cream The World Health Organisation recommends 35ml for an adult – that’s around seven teaspoons: one for the face/head and neck, one for each arm and each leg, and one each for your front and your back.
  • Reapply sun cream regularly Every two hours.
  • Spend time in the shade Particularly between 11am and 3pm when the sun is at its most intense.
  • Cover up with clothes, a hat and sunglasses.
  • Remember to apply sun cream to children in the UK and abroad.
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