Sunscreen Lessons - What You Should Know

Posted by James Marshall on

Sun damage is a prick of a thing; sure it feels nice to feel the sun on your skin, and get some vitamin D in your body, but we all know the lethal dangers of too much exposure to the sun.

You may also be aware that I am working on a natural sunscreen for SETT Surf. It is still a work in progress, but I wanted to update you on what I have learned during this process, so that you may be a bit more informed next time you go and grab some sun protective skincare products (be it SETT Surf's or otherwise).

Disclaimer: this is based on my research and discussions, feel free to chime in and clarify or correct anything I may have misunderstood, in the comments section below.

First lesson - not all sunscreens protect us from all harmful UV rays

Uhhh, what? Sunscreen doesn't protect us from the sun?!

Well not in all cases, apparently. Different active ingredients protect from different rays. The table below summarises common active ingredients and how effective they are, which is supported by a great article from Sarah Wilson

According to the Skin Cancer Council,  both UVA and UVB are now believed to play a role in the development of skin cancer (until recently it was thought it was mainly UVB). UVA (the 'aging rays' that cause wrinkles etc) can also penetrate glass, so be aware of this if you spend lots of time driving in the sun, for example.

Sun Smart say that SPF 30 blocks out 96% of UV rays, and SPF 50 filters out 98%, but in any case be sure to get a 'broad-sprecturm' product that covers UVA and UVB rays.

What is not 'natural' about existing suncream?

In short, there are two types of sun protection which we can rub into our skin. The first is chemical sunscreen which breaks down harmful rays as they enter your skin. The second type is mineral or physical sunscreens which create a barrier  - quite literally a thin layer of metal on top of your skin - that reflect or scatter the harmful rays.

Chemical sunscreens are under the microscope for a number of reasons. For starters, because they sink into your skin (this is why instructions state to apply 20-30 minutes before sun exposure as they need to sink in to be effective). However, there is concerns that by sinking in, they then get into your bloodstream where they could do damage to the human body. The most common issue I have read about here is the active ingredient Oxybenzone may be a hormone disruptor - check out the Environmental Working Group for more info. 

Additionally, some chemical sunscreen ingredients have been found to wash off of swimmers and bleach coral - Not Cool! In fact, just last month Hawaii started the wheels in motion to ban the use of Oxybenzone based products in order to protect their coral reefs. Other chemicals to look out for are Octyl Methoxycinnamate (which apparently becomes more toxic when exposed to the sun (which really doesn't make sense...) as well as Benzophenone and butylparaben.

Covering up also minimises the amount of suncream needed, and therefore leaking into the ocean


In comparison, a mineral or physical sunscreen's active ingredients are usually Zinc and Titanium Dioxide. These are designed to sit on top of your skin which is why they can sometimes leave a heavy feeling or not appear to sink into the skin - but they are effective as soon as applied, no waiting to hit the waves! Zinc is a natural element which is generally required for normal human health, in small quantities. What's more, mineral sunscreen is usually combined with organic ingredients like natural oils and butters to give a nice consistency which means you can get other benefits like moisturisers and antioxidants etc. Note also that in the table above, Zinc gives the best overall coverage too - BOOM! 

The nano vs non-nano argument

Nano particles refers to the size of which the ingredients are broken down into, and is another one with passionate views on both sides. Those against nano particles claim that by making an ingredient particle nano sized (measures less than 100 nanometers) it increases the chances the particle can penetrate deep into the skin, and your bloodstream, instead of sitting on the surface. However there is no strong evidence of long term health risks - we simply just do not know yet, as the Australian Cancer Society point out. At this stage the safer bet seems to be avoid nano-particles if you want to avoid the speculated risks. 

There is more information, particularly on the regulatory side, that I am combing through but will not bore you with. I do hope however that the above helps you understand a bit more different sun protection products, and some of the things you should be thinking about when you buy them...I am certainly thinking about them in the development of SETT Surf's sunscreen! Stay tuned...

Again, anything you think is not 100% accurate here, please comment below so we can have the best information possible - thanks!

Cheers – talk soon,

James (Mammoth)

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  • Hey Camilla, thanks for your kind words – stoked its useful! The only health concerns I have read about really high SPF is that there could be increased likelihood of the chemical risks noted above, as they are needed in higher concentrations to increase the SPF rating. Some SPF measures only look at UVB too which causes red sunburn, but not UVA which can still damage skin and cause cancer – hence broad spectrum is important.

    I have read that higher SPF can lead to careless consumer behaviour – i.e. ‘SPF 100 is twice that of SPF 50, so I will be safe for twice as long’ which isn’t true, you should still reapply every few hours. Similarly people not covering with a hat or t-shirt when they should because they feel safe. I understand now that in Europe, Australia and NZ that SPF 50+ (means it measured SPF 60 in testing) is the highest SPF rating you can advertise to try and mitigate that consumer behaviour risk.

    Cynics also claim it is simply a way of making more money, since the incremental protection is small (98%-99%?), but the price is often significantly higher.

    Phew…feels like another blog post haha!

    James on
  • Thanks James, I didn’trealise the difference in physical/chemical so a good point to look out for. I have heard anything above SPF50 is likely doing more damage to skin than adding more protection – any thoughts?

    Camilla on

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