Sunscreens

WHICH? REVIEWS: Sunscreens

Our rigorous tests produced eight Best Buy sunscreens and three Don't Buys. We explain what the labels on the bottles mean and how much you should use to prevent sun damage to your skin.

Most sunscreens are designed to protect your skin from two types of ultraviolet (UV) radiation emitted by the sun - UVA and UVB. But our tests found that a sunscreen that protects well against UVB doesn't necessarily protect well against UVA, and vice versa.

UVB, in particular, is known to cause sunburn. Skin damage from sunburn is strongly linked to several kinds of skin cancer, including basal and squamous cell carcinomas and the most serious type, melanoma (also known as malignant melanoma). If melanoma is not diagnosed early, it can spread to other parts of the body and be fatal.

A sunscreen's ability to absorb UVB and protect against sunburn is shown by its sun protection factor (SPF), such as 15.

Less is known about UVA. For many years, UVA was simply thought to contribute to skin ageing and wrinkling; however, the World Health Organisation cites recent studies that suggest a strong link between UVA and skin cancer.

You can find out our Best Buy recommendations by taking out a £1 30-day trial to www.which.co.uk Below, we explain more about the features of sunscreens.

Do sunscreens have a 'shelf life'? If so, how long can they be kept for without losing their effectiveness?

Sunscreens should remain effective for many years if they are not exposed to high temperatures, and if contaminants, such as sand or dirt, do not get into the bottle. However, as sunscreens are often used on beaches in warm weather, it is very easy for this to happen, so it's best to err on the side of caution.

Isn't some sun good for you? If you wear sunscreen all the time, you risk not getting enough vitamin D and developing rickets.

A little sun is good for you. Our bodies use UV radiation from the sun to produce vitamin D, which is crucial for healthy bones.

But for most of us, around 15 minutes of exposure a day on the hands, arms and face during the summer is enough to keep up vitamin D levels. Any more, and we risk burning ourselves.

Is it safe to build up a natural tan through careful, gentle exposure to the sun?

As a tan is a sign that the skin has been damaged, and this damage will increase your risk of skin cancer, tanning should never be considered safe.

However, some sunlight is good for you and, if you develop a light tan as a result of careful exposure for short periods of time, then this is not unacceptable.

The darkening and thickening of the skin that results from tanning can also provide protection against sunburn or reddening of the skin, which should be avoided at all costs.

Some of the face creams I buy and the foundation that my 14-year-old daughter wears claim to offer sun protection. Is it safe to use these on their own?

Which? has not tested the effectiveness of these products. However, for recreational summer sun exposure (on a beach or in a park, for example), they should not be used in place of a conventional sunscreen.

Moisturisers and make-up are rarely water-resistant and will not remain on the skin in the way that a sunscreen can. And, though moisturisers and make-up may have an SPF to protect mainly against UVB, most sunscreens contain UVA filters as well.

If my son applies sunscreen to his face, arms and neck before school starts, will it still give him protection during the lunch hour, when the sun is at its strongest?

A water-resistant sunscreen - even if your son will not be going anywhere near water - with a minimum SPF15 is the best way to try to ensure that protection lasts this long. This is because water-resistant sunscreens are formulated to bind very well to the skin. But you may find that they are a bit stickier than sunscreens that are not water-resistant.

So what's the best suncreen for you? By taking out a £1 30-day trial to www.which.co.uk you can discover all you need to know about barbecues and find out our Best Buy brands.

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