With the onset of summer and the inevitable increase in exposure of our skin to the sun’s rays, it’s worth considering how to take the best care of our skin while still making the most of all that summer has to offer.
What’s so damaging about sunlight?
Our skin is damaged by an excess of the ultraviolet (UV) wavelength of sunlight. The early visible effect of excessive UV exposure is sunburn, which is the inflammatory response triggered by UV light. While sunburn is visible, the changes going on in the deeper layers are not. UV light can damage our skin’s DNA, sometimes irreparably. It also triggers the generation of oxidative molecules (free radicals) that can damage our collagen, elastin and other structures in the skin, as well as our skin’s DNA. When skin DNA is damaged, we increase our risk of developing skin cancers, while damage to collagen, elastin and our skin’s matrix will speed up our skin’s ageing. To complicate matters, UV light can reduce our skin’s ability to mount an effective immune response, further raising the risk of developing skin cancers.
How does our skin protect itself?
Our skin has built-in mechanisms that protect it to some extent from the harmful effects of UV light. Firstly, our cells can repair damaged DNA. Secondly, our skin contains melanin, which is very efficient at absorbing UV light. And finally, it contains antioxidants that can neutralise the free radicals that damage the skin, however these are depleted following exposure to UV light.
So how can we boost our skin’s natural defences?
When we really can’t avoid exposing our skin to the sun, sunscreen is our first line of defence. There are two types of sunscreen. Physical sunscreens, made with zinc oxide or titanium dioxide, which protect the skin by reflecting, scattering and absorbing UV light. Chemical sunscreens, on the other hand, directly absorb UV light and convert it to heat energy.
While physical sunscreens are generally considered safe, there are concerns about the safety of chemical sunscreens. Some of the active ingredients in chemical sunscreens can be absorbed into the body to the extent that they can be detected in blood, urine and breast milk. Yet their safety is still unproven. Of particular concern is oxybenzone, a common ingredient in chemical sunscreens, which may have hormonal effects (1). A number of ingredients commonly included in chemical sunscreens, including oxybenzone and octinoxate, are also potentially damaging to coral reefs. In some parts of the world - Hawaii, Palau and Key West - sunscreens containing reef-damaging chemicals are banned, however no such ban exists in Australia. Unfortunately, because chemical sunscreens are more ‘invisible’ than physical sunscreens, they are far more popular.
We believe the personal convenience of chemical sunscreens is not worth the risk to our health or that of the environment. When asked by our customers, we recommend choosing a certified organic sunscreen that uses non nano zinc oxide as its active ingredient.
Our skin contains natural antioxidants, and to some extent these protect our skin against free radical damage caused by UV light. So it makes sense that consuming a diet extra rich in antioxidants could make our skin even more resilient to the damaging effects of UV. However this is not always the case.
We looked at the benefits of increasing dietary antioxidants - vitamin C, carotenoids, flavonoids and polyphenols, all of which are found in many commonly consumed fruit and vegetables
It seems that increasing our vitamin C intake has no real protective effect, at least when consumed in its synthetic form. In the study we looked at, oral vitamin C supplements were given at a dose that raised both blood and skin levels of vitamin C. However no additional UV protective effect was seen. This was surprising, because vitamin C is known to be an important protector against UV light in the skin.
In contrast, diets rich in carotenoids did have benefits, in particular lycopene and lutein, which are abundant in tomatoes. However a minimum of 12 weeks supplementation at a fairly high dose (around 55g tomato paste per day) was required to show a protective effect.
The polyphenol antioxidant found in green tea, and flavonoid-rich cacao powder were also effective - they reduced the size of sunburn after UV irradiation (2, 3).
Interestingly, many of these studies have looked at supplementing the diet with a single substance, sometimes synthetic. It may be that consuming a plant-based diet rich in a range of antioxidants, including sufficient quantities of proven protectants like green tea, cocoa and tomatoes, will have additive and synergistic effects, offering extra UV protection.
3. Skin care products
Applying antioxidants directly to the skin is another means of protecting the skin against UV damage. A range of studies have given interesting results.
Application of vitamin E directly to the skin was found to be protective. Vitamin E seems to exert its protective effect on the skin both through its antioxidant activity and by directly absorbing UV light.
Another promising study showed that applying green tea polyphenols gave protection against UV-induced damage (4).
Although it is well established that consumption of carotenoids can help protect the skin against UV, the effect of topical application of carotenoids has not been studied. However, we can make some assumptions from a couple of findings. Firstly, topically applied beta-carotene is known to be readily absorbed into the skin and converted to the active form of vitamin A (5). In addition, where infra-red light was used to generate free radicals in the skin, the application of a cream containing beta-carotene protected the skin from free radical formation. (6). Therefore it seems likely that applying carotenoid-rich products to the skin will boost the skin’s antioxidant levels and protect against free radicals from UV light in the same way it protects from free radical production by infra-red light.
Vitamin C is another substance that has been shown to be protective against UV, and also to stimulate production of collagen in the dermis. So to some extent vitamin C can both protect from UV damage and help repair the damage caused by UV light. The difficulty for skin care manufacturers is to deliver the active, water-soluble form of vitamin C at the low pH that allows its absorption. To make things more difficult, the water-soluble form of vitamin C loses its activity after a few weeks in an aqueous solution, and is readily degraded by light. Much work is continuing to find a way to deliver an active, usable form of vitamin C to the skin.
Which Mokosh products can help?
All Mokosh moisturisers, as well as our Makeup Remover & Cleansing Oil, contain vitamin E, carotenoids, and other antioxidants including polyphenols. Our Facial Cleanser, Exfoliator & Mask, once activated by mixing with water, is also rich in antioxidants, and contains the active form of vitamin C.
We believe that the regular application of our products will help maintain good levels of these important antioxidants in the skin. In addition, after a day in the sun, when your skin’s levels of antioxidants will be depleted, application of our products should help replenish their levels, counteracting some of the damaging effects of UV light. Another strategy would be to apply our moisturisers before going into the sun, and before applying sunscreen, so that your skin will receive a boost of antioxidants before it is exposed to UV light.
In addition, our products contain natural anti-inflammatory molecules that can help soothe the inflammation of sunburn, while their good levels of essential fatty acids can help rebuild the skin’s barrier function (read more about this here).
However, as most health professionals would say, prevention is better than the cure. Avoiding the sun when UV levels are at their highest should be a priority. When you can’t avoid the sun, be sure to wear protective clothing and sunscreen. Apply antioxidant-rich, well formulated products to your skin, and eat a really good diet, rich in fruit and vegetables. Your skin, like the rest of your body, will thank you for it!