SPF guide: How to protect your skin like a pro in the heatwave

Rosie Fitzmaurice

London is sizzling. However by now we all know the dangers of sun damage, so there's really no excuse any more for getting burnt to a crisp – sunbathing is officially uncool.

Indeed, startling new research from Cancer Research UK has found that skin cancer rates in the UK have risen some 45 per cent in 10 years.

Advances in the skincare industry mean there are plenty of clever SPF products available to suit all lifestyles and skin types – now you really can pick your sun protection as you would a moisturiser.

From chemical to mineral and reef-friendly sun creams, to whether to go for SPF 30 or SPF 50, we asked dermatologists for their top tips when it comes to protecting your skin like a pro this summer.

Consultant dermatologist at the Cadogan Clinic and author of The Skincare Bible, Dr Anjali Mahto, says: "Aim for a broad spectrum sunscreen which offers protection against UVA and UVB with an SPF 15-30 as the minimum criteria."

Invest in a decent facial sunscreen

It's worth investing in a separate facial sunscreen, too, which you can carry with you year-round – they're typically lighter in formula and less likely to clog the pores on your face, which will probably mean you use it more.

"Many sunscreens for the body are quite heavy and may not be suitable for blemish prone facial skin," Dr Mahto says. "The benefit of a facial sunscreen is that it may also contain added beneficial ingredients that body sunscreens lack."

"It's a bonus if the sunscreen provides protection against visible light and infrared-A radiation," she adds. "Visible light and infrared generate free radicals, which can contribute to ageing. One of the current difficulties is that there is no universal system for either of these."

Enhance your protection with an antioxidant

It's a good idea to enhance your sun protection by using either an SPF containing antioxidants or wearing an antioxidant serum, such as vitamin C, with your sunscreen, Dr Mahto says, as it can help to neutralise the free radicals that the sun's rays generate.

Dr Tiina Meder, dermatologist and founder of Meder Beauty Science, agrees, but warns it's important to take care when combining other skincare products, as some ingredients can negatively interact with sunscreens.

"Obviously, it’s not recommended to use products containing retinol or hydroxy acids before going out in the sun and some natural oils can actually dissolve sunscreen if applied just before application. I recommend using effective but simple moisturisers – based on hyaluronic acid or glycerine – before applying sunscreens. And if using facial or body oils wait until those products have fully absorbed before application.

Here are a few of our favourite facial sunscreens, which are packed full of antioxidants and anti-pollutants, perfect for city living.

Dermalogica's Prisma Protect SPF 30 (£58)

Dermalogica prisma protect

Launched earlier this year, Dermalogica's multitasking light-activated Prisma Protect SPF 30 provides broad spectrum defence against UVA, UVB and visible light. The chemical sunscreen uses clever cosmetic drone technology, which is activated by visible light, to deliver a photosensitive ingredient (exogenous chromophore) to the skin to boost luminosity, while matcha tea neutralises free radicals and helps to defend skin against pollution. It's also vegan, cruelty and paraben-free.

Coola Mineral Cucumber Face SPF 30 (£36)

COOLA

If you have oily or acne-prone skin, then Coola's featherweight SPF 30 mineral cucumber face moisturiser is the one for you. The velvety formula instantly absorbs into the skin, without leaving an overly matte finish, it's also packed full of skin-nourishing goodness and antioxidants like evening primrose and linseed to soothe and hydrate, plankton extract (a known phyto-protector) and omega-rich açaí oil to strengthen and rejuvenate. The brand doesn't use parabens, GMOs or oxybenzone (making it reef-friendly), too.

Dr Russo Once A Day SPF 30 Invisible Face Gel (£26)

Dr Russo's Once A Day SPF 30 Invisible Face Gel (£26)

If you're guilty of forgetting to top up frequently, try Dr Russo's Once A Day SPF30 Invisible Face Gel, another featherweight product, which uses long-wear technology to prolong protection – though you should of course still exercise caution with your sun exposure and be sure to reapply regularly if you're swimming, for example – it also comes with a click-brush applicator for easy on-the-go application. The formulation contains hyaluronic acid and antioxidants like ferulic acid and vitamin E to help repair signs of DNA damage, too.

Jane Iredale's Powder Me SPF (£36)

Jane Iredale Powder Me SPF soldier nude

If you don't like the feel of sun cream on your face at all then try Jane Iredale's Powder Me Dry and chemical-free sunscreen for face, body and scalp, which is perfect for dusting along a parting. The product contains a physical filter titanium dioxide for sun protection, as well as pomegranate and pine bark extracts to nourish and calm the skin.

Mineral suncream versus chemical

There are generally two types of suncream: mineral (or "physical") and chemical, with the latter being more commonly found in pharmacies and beauty stores.

"Physical sunscreens create a physical barrier between your skin and the sun," explains Dr Gabriel Serrano, dermatologist and founder of cult Spanish skincare company Sesderma. "They aren’t usually absorbed into the skin but remain on the surface, two of the most common are titanium dioxide and zinc oxide. Meanwhile chemical sunscreens absorb the sun's rays and penetrate different layers of the skin as opposed to just sitting on top of the dermis."

Chemical SPFs have historically been more popular because they tended to have a lighter consistency and were easier to apply while mineral sunscreens often had a chalky texture and caused whitening of the skin.

However, chemical sunscreens also have more allergic potential, says Dr Natalia Spierings, medical director of Dermatica: "Chemical sunscreens cause 2 per cent of all contact allergies in skin. They're also photodegrade – meaning they get destroyed by sunshine hence you have to reapply every 2-3 hours, whereas physical sunscreens just sit on the skin and reflect sunlight."

Therefore mineral sunscreens, which often have a matte finish, can often better suit people with sensitive or acne prone skin – just be sure to remove them properly. Dr Sharon Wong, consultant dermatologist at HCA, says: "Newer generation mineral sunscreens use more refined technologies to include smaller mineral particles that overcome the previous drawbacks." She recommends cult favourite Heliocare 360 in a gel formulation.

Reef-safe suncream​

It's also worth noting that oxybenzone and octinoxate, two of the most common ingredients found in chemical sunscreens, can have a detrimental effect on ocean ecosystems, so much so that they have been banned in coral-rich places like Hawaii and Key West.

"Certain sunscreens promote viral infections in coral reefs, contributing to coral bleaching in areas with low water renewal where many tourists visit,"says Charlotte Vohtz, founder of ocean-friendly skincare brand Green People.

The natural skincare brand has eliminated the use of the two aforemenioned toxic chemicals, as well as zinc oxide (a mineral UV filter), which in the presence of chemical pollutants and heat or sunlight can cause the release of zinc ions which are harmful to aquatic life. Instead the brand uses naturally occurring titanium dioxide and Isoamyl P-methoxycinnamate, a naturally derived chemical sun filter from cinnamic acid, which is found in cinnamon tree leaves. All products now also come in plant-derived sugar packaging.

Green People SPF 30 Reef-Safe sun lotion

SPF 30 or 50?

Ian Taylor, cosmetic scientist for Green People, says it's more about making sure you've applied enough in the first place.

"SPF 30 filters out 97 per cent of UVB radiation, and SPF 50 filters out 98 per cent of UVB radiation – an increase of only 1 per cent. It's far more important to apply sufficient sun lotion and to reapply frequently to maintain protection," he says.

"Studies have shown that applying half the correct amount of sun lotion results in protection equal to the square root of the claimed SPF," he continues. "This means that using half the recommended amount of an SPF30 will only give protection of between SPF5 to SPF6, and using half the amount of an SPF15 will give protection between SPF3 and SPF4."

The six teaspoons rule

So how much is enough? The official guidelines given by Colipa (Association of European Cosmetics Industry) is 2mg/cm², which corresponds to roughly a teaspoon worth for the face and neck, says Dr Serrano. "Apply at least half a teaspoon to each arm, and then a teaspoon to each leg, front of body and back of body – he recommends Sesderma's SPF 50 Repaskin body gel cream.

Sesderma SPF 50 Repraskin body gel cream (£28.80)

It's also best to apply your sun protection indoors, up to 30 minutes before sun exposure.

"If applied in the sun, up to 50 per cent of the quantity of the sun cream applied to the skin can evaporate before it has a chance to bond with the skin and therefore becomes less effective. Sun protection should always be applied to cool, clean, dry skin in the shade (ideally indoors) 15-30 minutes before going out into the sun."