Summer Health

Sun exposure

The intensity of the sun’s rays will vary a lot between geographical location, time of year (interesting to note that it is at it’s most intense in the UK in late June), The time of day (strongest from 11am – 3pm), weather conditions and reflection (such as snow, sand, water or bright surfaces). The UV index from the Met Office provides some helpful information on UV levels in the UK.

A quick sun strength test that works anywhere in the world is the ‘shadow rule’. If your shadow is shorter than your height, the sun intensity is strong and you’re more likely to burn. So you’ll need to take extra care to protect your skin.

Skin colour also influences safe sun exposure. People with genetically darker skin are at a relatively lower risk of burning, but potentially at higher risk of vitamin D deficiency in the UK. Those with darker skin tones may therefore need a little more time in the sun to produce the same amount of vitamin D as people with lighter skin, although should still take care to avoid sunburn (NICE, 2016).

For all of these reasons, it’s therefore impossible to give one standard response to how much sun exposure is safe for us each to have. Being informed, however, should help us to make sensible decisions for ourselves on a daily basis.

UVA is associated with skin ageing, as it affects the elastin in our skin and leads to wrinkles, leathery skin and pigmentation. It penetrates more deeply than UVB and can reach through glass. UVA protection in sunscreen is rated by stars, from 0-5. It is recommended that we look for broad-spectrum UVA and UVB sunscreen products, ideally with a UVA rating of 4 or 5 stars (alongside a high SPF).

UVB is more responsible for sunburn and has stronger links with skin cancers. A sunscreen with high SPF (sun protection factor) helps to block UVB and prevent sunburn. The British Association of Dermatologists recommend using a sunscreen with an SPF of 30+ as a satisfactory form of sun protection, alongside protective shade and clothing.

NB., The SPF integrated into other products (primers, moisturisers, foundations etc.) can’t necessarily be relied upon to give us the same level of protection as a standalone sunscreen. We tend to use smaller amounts and they may be less rub-resistant and water resistant. Also, moisturisers containing an SPF may not contain any UVA protection and therefore don’t necessarily protect against UV ageing.  It’s therefore advised to use a standalone sunscreen alongside our skincare routine and make-up.

Mineral sunscreens tend to contain titanium dioxide or zinc oxide, which reflect UV radiation away from the skin. These can be thought of as ‘mirrors’, bouncing the light away. These sunscreens may also be known as ‘physical’, ‘natural’ or ‘reflective’.

Chemical sunscreens absorb UV radiation and give it back out as infrared. These are like sponges, mopping up UV radiation that reaches the skin. They may also be known as ‘absorbers’.

The type of sunscreen you choose is really a personal decision, but do look out for the SPF and UVA star rating on any product you buy. One thing I have noticed is that mineral sunscreens don’t often have the UVA star rating on their label. You might therefore need to do a little more digging to check that they have appropriate broad-spectrum coverage.

I am currently using this sunscreen from Heliocare on my face and I like that it is light and not shiny and doesn’t aggravate my acne-prone skin.

I also use this broad-spectrum, SPF 30 scent-free suncream from Green People for my body.

Finding a broad-rimmed sun hats at a reasonable price is always a mission. I recently bought this one.

I have my eyes on these utterly glorious tents for picnics and beach days, so we all have somewhere to escape from the sun while still being outside. A girl can dream!

Studies have suggested that many people apply less than half the amount of sunscreen required to reach the level of protection stated on the packaging (British Association of Dermatologists, 2013).

While the exact amount you need will depend on the formulation, a rough ‘rule of thumb’ is that we need around 6-8 tsp (30-40ml) of sunscreen to cover our bodies appropriately (NICE, 2016).  Check the label to see how much is recommended to achieve the stated sun protection. If sunscreen is applied too thinly, the amount of protection it gives can be dramatically reduced (i.e., using too little SPF 15 may only be achieving around SPF 5 or less).

Other sunscreen tips

Apply sunscreen 15-30 minutes before you go outside. If you’re going out into the sun for a prolonged period of time, it is recommended that you apply again at the time you go outside. This will help reduce the risk of missing patches. More is generally better.

Re-apply at least every 2 hours and immediately after swimming, sweating and towel drying, or if it has rubbed off.

Water-resistant products are not necessarily towel-resistant! Up to 85% can be removed with towel drying.

Check the expiry date – most sunscreens have a shelf life of 2-3 years, and should be replaced after their expiry. And store it in a cool, dark place, as extreme heat can damage the protective properties.

Don’t rely on a high SPF to skip re-applying sunscreen frequently, or use less product. High SPF sun creams can sometimes create a false sense of security, so do not rely on them to stay in the sun longer or not take other sensible shade-seeking precautions.

Sunlight exposure (between April – October) to commonly uncovered areas, such as our forearms, hands and lower legs, that we get incidentally during daily activities if outside, should be enough to boost vitamin D levels, without ever getting a heavy tan or burning.

Remember that skin produces plenty of vitamin D long before it starts to burn, and won’t continue to make more vitamin D after a short period of time in the sun. We don’t need to sunbathe, or spend prolonged periods of time in the sun to boost vitamin D levels. For those at higher risk of skin cancer, however, protecting the skin from the sun is a priority and so vitamin D may need to be obtained from other sources (such as diet or supplements) as necessary. Please discuss this with your doctor if required.

It is difficult to say exactly how long every individual needs to spend in the sun to achieve sufficient vitamin D levels, as it will depend greatly on skin type, risk factors and sunlight intensity (as discussed above). Darker skin tones may need to spend longer in the sun to achieve the same levels of vitamin D, and/or look to alternative sources of vitamin D rather than relying on sunlight alone.

Please read this article on Vitamin D for more information on those alternative sources.

Alongside sunscreen use, there are various other precautions that we should take to reduce our risk of sun damage.

Wear a hat with a large brim (at least 3 inches) and sunglasses (with the appropriate CE mark).

Wear light-weight, long-sleeved clothing when in the sun. Sunscreen is not an alternative to covering up with suitable clothing and seeking shade, but it does offer additional protection. No sunscreen, no matter how high the factor, can provide 100% protection.

Stay in the shade between 11am and 3pm, particularly when it’s sunny.

Keep babies and young children out of direct sunlight, and cover them with suitable clothing, encourage time in the shade and always use a sunscreen. To ensure they get enough vitamin D, all children under 5 are advised to consider vitamin D supplements.

Avoid sunbeds and deliberate sunbathing. Take care to never burn.

Remember, even if it is cool or cloudy, it is still possible to burn.

There is no safe or healthy way to get a tan from sunlight, or sunbeds. And don’t rely on a tan to offer your skin protection. A tan offers a SPF of around 3 – not nearly enough to protect ourselves from sun damage (Cancer Research UK, 2016)

For more information, take a look at the NHS website on sunscreen and sun safety here.

And this list of 12 sun safety myths debunked from Cancer Research UK is well worth a read. I learnt a lot!

Please tell your doctor immediately about any changes to a mole.

Content kindly reviewed by Dr Eve Sloan-Brittain, GP with a special interest in dermatology.