I got asked to write a piece about zinc oxide - well actually about Zinka, a brand of sun cream that includes zinc oxide. I’m a geek, and I think the zinc oxide story is fascinating. Sadly in the version that was published, it was cut quite heavily, and the lovely people at thesuncareshop.com who sent me the products, inexplicably had their web address changed so it was wrong. As such, I’d rather you read this original version than the slightly staccato, and not entirely accurate one, that’s on the Mail website

By Claire Coleman

Think I look utterly bonkers in these pictures? I don’t blame you. Actually I blame Livia Firth. Last week, she posted a picture of herself on social media site, Instagram. Photographed on the beach, her face adorned with pink and orange stripes, she commented ‘Did I find the perfect recipe for being in the sun wrinkle free although looking like a lunatic? Just discovered Zinka which is [what] surfers use in California to stay in the sun all day.’

The creative director of ethical brand consultancy, Eco-Age, may well be right. Zinka (£7.49, thesuncareshop.com), a brand of sun protection developed in Southern California in 1986 is a bit of a cult product among surfers. It was developed after a couple of guys decided that they wanted to make a more colourful version of the white zinc that lifeguards - and cricketers - used to wear on their noses to protect them from the sun.

Zinc oxide has been used as a topical skin product for millennia with references to its application as a treatment for wounds and various skin conditions found in literature dating back as far as 500BC. Even today you’ll find it in ointments designed to treat nappy rash and in many antiseptic creams. But, it’s its ability to screen out UV rays that makes it such a valuable ingredient in sun cream.

It comes under the heading of physical sunscreens, or reflectors - these are ingredients that form a physical layer over the top of the skin and reflect the sun’s rays, rather than absorbing them. The other most common ingredient that falls into this category is titanium dioxide, which you’ll also find in many sun creams, including Zinka. Many people who have sensitive skin find that they’re better off with ingredients like this as, unlike the other type of sunscreen, often known as chemical sunscreens, or absorbers, they tend to irritate the skin less and don’t block pores. However, what makes zinc oxide such a hero product is the number of different types of the sun’s rays that it protects the skin from.

The two types of ultra violet light that we worry about are UVA, associated with ageing and skin cancer, and UVB, the type of light that burns the skin, but also contributes to skin cancer too. The best types of sun cream are called broad spectrum sun cream as they protect against all these types of light, but often sunscreen ingredients only protect against part of the UV light spectrum, so to make sure you’re protected against all of it, you have to mix together a cocktail of sunscreen ingredients. But, zinc oxide is not only effective on all the UVB rays, but also all the UVA rays too, making it the broadest spectrum sunscreen ingredient available. And, unlike some sunscreens whose efficacy diminishes over time, zinc oxide is photostable which means, as long as you haven’t rubbed it off, sweated it off, or washed it off, it offers the same protection hours after you put it on as it did when you first applied it.

‘In my opinion, it’s the best sunscreen ingredient for providing protection against the long wavelength UVA rays that penetrate deeply into our skin’s dermis layer, ravaging our collagen [the protein that keeps skin firm] and contribute heavily to hyper pigmentation,’ says Harley Street cosmetic dermatologist, Dr Sam Bunting.

What’s [itals]not[/itals] to love? Well, to be honest, the colour. Until Zinka came along and started making it in crazy colours, zinc oxide was the thick white paste that you’ll remember seeing on the noses of Aussie cricketers. And most people who want protection from the sun don’t want to look like they’ve been whitewashed. However, advances in technology have led to the creation of micronised and nano forms of zinc oxide where the particles are anything from two to four times smaller than the zinc oxide found in previous sun creams.

‘The particles are very small which means they don’t appear white, but still cover the whole skin and act like tiny mirrors, reflecting UV light. It makes the product more aesthetically pleasing, but just as efficient,’ explains Dr Emma Meredith, Director of Science at CTPA (the Cosmetic, Toiletry and Perfumery Association).

So why doesn’t every sun cream in the world just use nano or micronised zinc oxide? After all, it doesn’t look chalky, it’s stable, and it protects against all the UV rays we’re worried about.

Well, there are a few issues. While the FDA, the US body that regulates ingredients in cosmetics, has no problem with zinc oxide and includes it on the list of allowed sunscreen ingredients, as does Australia, in Europe, it doesn’t feature on the equivalent list.

‘In the EU there are lists of ingredients known as positive lists which indicate the ingredients have been deemed appropriate for certain functions. There’s a list for preservatives, for colours, and for UV filters,’ explains Emma Meredith. ‘If you want to put a preservative into your cosmetic product, you must choose an ingredient from the positive list for preservatives. Similarly, if you want to put a UV filter into a product, you have to pick from the positive list of UV filters. Zinc oxide isn’t currently on the positive list - for historic reasons that meant only absorber-type sunscreens were listed. That doesn’t mean you’re not allowed to include it in a sun protection product, as it is an approved skincare ingredient, but if you want to say your product offers sun protection, it can’t be the only UV filter in the product.’

Even in parts of the world where it can be used, some people have expressed concern about nanoparticles and how they interact with the human body, thanks in part to a campaign by environmental group, Friends of the Earth, who warned of various potential adverse effects, based mostly on studies in mice where they had been shown to kill brain stem cells and destroy colon cells. However, despite the hypothetical possibilities, the evidence to date has shown these concerns to be unfounded as nano particles of zinc oxide don’t appear to penetrate the skin or reach the bloodstream. In fact the only risk to health associated with zinc oxide is if you inhale it. In the short term, this can cause something called 'metal fume fever', a flu like illness, and, in the long term, respiratory problems. But this is only a risk when it’s used in a powder or a spray. In a cream, there’s not a lot to worry about - at least from a human health perspective.

Because there are some who believe that the zinc oxide that is washed into our seas can have a profound impact on the wildlife - which would be bad news for eco-fans like Livia. A study published last year in the journal of Environmental Science & Technology suggested that nanoparticles of titanium dioxide and zinc oxide washed into the sea react with sunlight to form new compounds which are toxic to phytoplankton - the microscopic algae that feed everything from small fish and shrimps to whales. And even scientists who originally thought that zinc oxide and titanium dioxide were better for coral reefs than chemical sunscreens, have now changed their minds.

‘Preliminary investigations demonstrate that they too can, for various reasons, be harmful to coral,’ says Professor Roberto Danovaro, Director of the Department of Marine Sciences at Marche University in Italy, who carried out a ten year study into the impact of four popular absorber sunscreens on coral. He has now concluded that from an environmental perspective, we might be better off using eco-compatible sun cream - which contains absorber sunscreens that have been proven not to damage coral - and to date only one such range exists, Aethic Sovee (aethic.com).

But back to Livia and her discovery of Zinka. I have to say that while it looks fun, and smells deliciously coconutty, it’s quite thick, quite greasy, and the orange one took a lot of scrubbing to get off. If you want to enjoy the benefits of zinc oxide, without looking like a toddler has scribbled on you, you might be better choosing one of the less brightly coloured options below…

Elizabeth Arden Pro Triple Action Protector SPF 50, £59, skinbrands.co.uk

A tinted formulation with zinc oxide, titanium dioxide and a host of antioxidants, all backed by a clinical paper testifying to its efficacy. It's quite thin but very easy to apply with a universally flattering colour that can be used alone, or as a base for makeup.

Skinceuticals Sheer Mineral Defense SPF 50, £35, my-dermacenter.com

A mattifying combination of just zinc oxide and titanium dioxide, with no absorber sunscreens, making it ideal for sensitive skins. A pleasant, non-greasy unscented cream that dries matte, leaving a very slight white cast on the skin, so best under makeup.

 

Melvita ProSun SPF 30, £19, uk.melvita.com

With zinc oxide and titanium dioxide plus moisturising oils, including sunflower seed oil. This mid-weight cream has a slightly herbal fragrance, it takes a while to rub in but does feel very moisturising.

Avene SPF 50 Tinted Compact, £24, lookfantastic.com

A combination of titanium dioxide and zinc oxide, this tinted compact is an almost solid cream that you apply using the sponge applicator provided. It comes in a range of shades and is ideal if you normally don't like to reapply your sun cream as it messes up your makeup.

Earth’s Best Mineral Sunscreen SPF 30, £9.99, feelunique.com

Many children’s sun creams, like this, contain zinc oxide and titanium dioxide as they’re less likely to irritate skin. This is quite a thick lotion and all the rubbing in the world won't get rid of the blue-white layer it leaves. Although at least you can see where you've applied it. As a result, it may be best for kids who are less concerned about aesthetics.