Sunscreen in the spotlight

27 June, 2010. Tags: Holidays Beach and Sun

Skin cancer is responsible for more than 1,600 deaths a year in Australia and that number is on the increase. It is widely accepted that the best way to prevent skin cancer is ensuring we apply - and regularly reapply - a high SPF sunscreen.

As a youngster I was not alone in being plastered in sunscreen by my doting mother. Slip, slap, slop was, and still is, the order of the day. But was she really doing the best thing for my health? Sorry mum, but there seems to be some evidence to the contrary.

In fact, concern is growing that sunscreens may be contributing to exactly the problem they were designed to combat – skin cancer. So, is there a chance that your sunscreen is bad for your health, or should you continue to slop, rather than slip or slap? A question we at Ikigai have been scratching our heads over for some time… here’s what we’ve learned…

Sunscreens work in one of two ways. They are either organic or inorganic. The former transfers the energy from the sun’s rays into a mixture of heat, fluorescence and a photochemical reaction, while the latter is like a mirror which rests on the surface of the skin and acts as a physical barrier, reflecting back the sun’s rays.

Organic sunscreens

First up, let’s take a look at organic sunscreens. We know that they deal with UV radiation by absorbing the energy from sunlight – and that is exactly the problem.

According to some researchers, this energy from ultraviolet light may be transferred to the DNA in skin cells, in the form of free radicals. You remember free radicals, right? They are those pesky little critters that cause cellular damage which leads to aging and sometimes to cancer cells forming. Free radicals are why we don’t smoke and we try to eat lots of fresh fruit and vegetables, not to mention applying antioxidants to our skin to fight their effects.

According to environmental and nutritional toxicologist, Dr Peter Dingle, “Common sunscreen ingredients Padimate O, para-aminobenzoic acid and 2-ethylhexyl-p-methoxycinnamate, when illuminated by sunlight, generate singlet oxygen, a potent free radical that has the potential to cause DNA damage, including strand breaks, when in contact with human cells.”

Yikes! But wait, there’s more… Dingle continues, “Research has shown that a number of UV filters frequently used in the formulation of commercial sunscreens cause increased endocrine (hormonal) activity… the Danish EPA found that three commonly used sunscreens showed hormonal effects in both animal and test tube studies.

More worrying is that these chemicals have been found in breast milk at concentrations known to have estrogenic effects.” Estrogen being, put simply, the female hormone, this may have gender-bending implications for babies and children of both sexes (adults deal better with fluctuations in environmental hormone levels).

Some sunscreen ingredients may make the skin more vulnerable to other chemicals such as pesticides, allowing them to more easily penetrate into the body. So, spraying yourself with DEET might not be a great idea anyway, but it’s an especially bad one when you are covered with sunscreen.

Guess what? It’s not all about us. Organic sunscreens may be bad news for the environment too. Researchers led by Roberto Danovaro have uncovered strong evidence to suggest that organic UV filters and preservatives such as parabens are contributing to the bleaching of hard-coral due to beach-goers and tourists dousing themselves in sunscreen before snorkelling reefs or taking a dip in the ocean.

Inorganic sunscreens

What about the alternative - inorganic sunscreens?

These contain ingredients such as zinc oxide and titanium dioxide, natural minerals which come from clay and beach sand deposits and work by coating your skin like paint. The benefit of this approach to sun protection is clear – not only are the ingredients natural, but their particles are too large to penetrate the skin and enter the bloodstream.

But there is a catch. Even these seemingly harmless mineral ingredients may, due to recent technological advances, be blasted down to ‘nanoparticles’ – microscopic pieces, which make the sunscreen clear rather than opaque, and are also capable of passing into your skin due to their tiny size.

The safety of nanoparticles is very much up for debate, with many commentators saying that they have not been researched enough for us to be sure they are safe – and that, anyway, particles that are tiny enough to pass through your skin, into your bloodstream and be distributed throughout your body surely can’t be a good thing.

You can get a free safe sunscreen guide from Friends of the Earth, which tells you all the brands to avoid, here.

Diet and cancer

There are a number of environmental factors thought to be contributing to the general increase in cancer rates globally. One area of concern, besides the proliferation of chemicals in our daily environment, is an imbalance in omega 6 and omega 3 fats in our diet today. Dr Mercola, an American natural health guru, goes as far as blaming this imbalance – rather than the sun – for skin cancer.

The idea that this imbalance is one of a number of contributing factors in cancer rates (although not specifically skin cancer) is also suggested by Dr David Servan-Schreiber, acclaimed author of the international best seller ‘Anti Cancer, a New Way of Life’.

So the theory goes, historically, our diets were perfectly balanced in omega 3 and omega 6. However, a change in the way we feed our animals – which are now rarely grass-fed – has led to the average person consuming dramatically more omega 6 fats.

Cancer, it seems, thrives on inflammation in the body, and omega 3 oils are critical in regulating and reducing inflammation. Omega 6, on the other hand, while it also plays an important role in the body, may be partly responsible for increasing inflammation and creating more favourable conditions for cancer to thrive. Whilst we shouldn’t cut out omega 6 completely, we should make sure it is carefully balanced with omega 3.

The primary sources of omega 6 are corn, soy, canola, safflower and sunflower oil, which are abundant in our diets. Omega 3 is found in flaxseed oil, walnut oil and oily fish. So increasing our intake of omega 3 rich oils, taking a fish oil supplement, and choosing organic, grass-fed animal products such as meat, milk, cheese, yoghurt and eggs are all important ways to reduce our chances of getting cancer.

Since UVA rays do their damage by creating free radicals to ravage our DNA, clearly a diet high in antioxidants, which scavenge free radicals, is another good way to protect ourselves from developing cancer. Many studies show that green tea is a powerful antioxidant and that the polyphenols it contains are powerfully protective against cancer. Similarly, lycopene in tomatoes helps protect your skin's cells by providing antioxidant protection.

Berries such as blueberries, raspberries and strawberries; garlic, broccoli, citrus fruits, carrots and wholegrains are also potent sources of antioxidants. Eating a diet rich in these foods may help to protect you against some of the harmful effects of sun exposure.

Going naked

Of course, rather than using sunscreen, there is another option – going naked. And by that, we mean covering up! We’re talking about slipping on a shirt and slapping on a hat, but skipping the sunscreen. Oh, and not going out in the sun between 10am and 3pm. That is not to say that we shouldn’t go out in the sun at all. We rely on the sun’s rays to generate vitamin D, crucial to building healthy bones, muscles and teeth, so allowing our skin a little gentle dose of sunshine each day, without sunscreen, is a good idea.

There is even some evidence to suggest that safe sunlight exposure (without burning) may actually protect against as many as sixteen different types of cancer.

Sunscreens have become a “get out of jail free card” which allow us to spend all day, every day, soaking up the sun’s rays with gay abandon. Maybe it’s time to reconsider their role – and our relationship with the sun. It’s time to treat both the sun, and our own bodies, with the respect they deserve.

Natural sunscreens from Ikigai

Sunscreen active ingredients to avoid

• 4-MBC
• Avobenzone
• Parsol 1789
• Cinoxate / 2-ethoxyethyl p-methoxycinnamate
• Escalol 506 / Ethoxyethyl-p-methoxycinnamate
• Homosalate
• Menadione
• Octocrylene
• Octyl-methoxycinnamate (OMC)
• PABA / para-aminobenzoic acid
• Padimate O
• Psolaren
• 5-methoxypsolaren (5-MOP)
• Dibenzoylmethanes
• Escalol 507 / octyl dimethyl para-aminobenzoate
• Eusolex 8020 / isopropyl dibenzoyl methane
• Hydroxy methoxy methylbenzophenone (mexenone)
• Methyl sinapate / methyl 3,5-dimethoxy 4-hydroxycinnamate
• Octyl salicylate
• Oxybenzone / benzophenone 3
• Padimate A / amyl para-dimethylaminobenzoate
• PBSA / 2-phenylbenzimidazole-5-sulfonic acid