Australia, despite being the lucky country in so many ways, is unlucky when it comes to sun radiation. The hole in the ozone layer (what protects the earth from much of the sun’s rays) unfortunately stretches along much of the eastern coast of our sun-drenched country. This coupled with high temperatures and the outdoor lifestyle so many of us enjoy has resulted in a staggering 750,000 people treated for non-melanoma skin cancer each year.
While adequate sun exposure has a host of benefits for human health, including production of vitamin D, overexposure can lead to damage and negative health impacts. As in all things, getting the right amount for our skin type, for the climate we live in and current season is the key. Avoiding the sun is not good for our health and, likewise, getting too much is also not optimal. I find that many of my patients are fearful of skin cancer and actively avoid the sun and as a consequence suffer health issues from insufficient sun exposure. You may wish to check out my other article on vitamin D to learn how much sun is enough for your skin type.
Sun radiation comes in the form of ultra-violet-A (UVA) and ultra-violet-B waves (UVB). Despite both of these waves associated with skin cancers, UVB waves are generally thought of as the most damaging to the skin. In order to protect your skin against radiation damage when we are exposed to extended periods of time in the sun, sunscreen in some shape or form is a must. Unfortunately most of the sunscreens on the market protect your skin at a price. Chemical based sunscreens work on different UV spectrums and are often combined to get a stronger effect and generally require a chemical reaction in the body to block impact of the UV rays. Active chemicals (meaning they protect against UV rays) commonly found in sunscreens have been shown to have negative impacts on our health. Some such as the common oxybenzone and oxtinoxate have been shown to be endocrine disruptors and can effect sex and thyroid hormones in human and animal studies. Other people develop skin sensitivities to sunscreen, and some skin specialists recommend natural based sunscreens as a better tolerated alternative.
If you are after more in depth information regarding sunscreen and its constituents and health implications check out the Environmental Working Group’s overview here.
There is less incidence of adverse reactions from mineral based sunscreens such as zinc and titanium dioxide. These are known as physical block outs, because they provide a mineral based or physical layer on the surface of the skin that prevents UV light and is not absorbed into the skin. Use of these mineral-based sunscreens offer a safer alternative to the chemical based oxybenzone and oxtinoxate types.
When examining sunscreen we use the common standard of SPF rating. SPF stands for Sun Protection Factor and it is a measure of a sunscreen’s ability to prevent UV radiation from damaging the skin. For example if it takes 10 minutes for your unprotected skin to start turning red, using an SPF 15 sunscreen in theory will prevent the skin reddening 15 times longer – which would equate to 150 minutes – or 2.5 hours. SPF does not equal the amount of protection per se, but rather indicates how long will it take for the skin to redden when a particular product is applied, as compared to unprotected skin.
Aside from natural mineral based sunscreens, there are a range of other food and plant based oils and substances that serve as mild natural sunscreeens due to their carotenoids and natural pigments. Even plain coconut oil or sesame oil has a mild ability to screen UV rays and protect the skin. See chart below for an overview of different sunscreen agents and benefits.
The very pigments that make blueberries blue and raspberries red protect those berries from oxidative damage from the sun. Plants have adapted to create inbuilt defence mechanisms to prevent free radical damage, and thus we can utilise some of the natural chemicals that these plants make, to protect our skin from the negative effects from the sun. Like any natural product there can be variability between batches and quality of the oil and due to different weather patterns and seasons the amount of carotenoids and actives contained in the oils may vary influencing the SPF potential. As such, I do not advocate using these oils in isolation or as a substitute to more reliable sunscreens when you do need good protection.
Making your own sunscreen is another possibility and ensuring it also has some zinc oxide in it can boost the UV protection considerably. I found this recipe for a natural homemade sunscreen and have adapted it. Get the recipe here.
Korać RR, Khambholja KM. Potential of herbs in skin protection from ultraviolet radiation. Pharmacognosy Reviews. 2011;5(10):164-173. doi:10.4103/0973-7847.91114.
Oomah, B.D., Ladet, S., Godfrey, D.V., Liang, J., & Girard, B. (2000). Characteristics of raspberry (rubus idaeus L.) seed oil. Food Chemistry, 69;1, 187-193, S0308-8146(99)00260-5.
Kostyuk V – Natural Substances for Prevention of Skin Photoaging: Screening Systems in the Development of Sunscreen and Rejuvenation Cosmetics. https://www.ncbi.nlm.nih.gov/pubmed/28661208
Kaur, C.D., Saraf, S. (2010). In vitro sun protection factor determination of herbal oils used in cosmetics. Pharmacognosy Research, 2(1), 22-25, 10.4103/0974-8490.60586