Can your sunscreen cause cancer? Does it decrease your vitamin D levels? With so many opinions flying around the web, it can be difficult to discern rumour from fact. We decided to take a critical look at the biggest sunscreen myths (and facts) out there today.
Sunscreen Reduces Your Vitamin D
The fact is that we get most of our vitamin D from the sun. The theory says that if we cover ourselves in a substance that blocks the sun, we won’t get as much vitamin D. What does the evidence say?
According to a systematic review presented at the National Sunscreen Summit in Brisbane in 2018, the research (which included both laboratory experiments and field studies) consistently showed no link between sunscreen use and decreased vitamin D levels. In two of the studies reviewed, regular sunscreen users had the same levels of vitamin D as non-regular users.
In Conclusion; Evidence outweighs theory in this case, and sunscreen does not appear to affect your vitamin D levels.
Nanoparticles from Sunscreen Are Toxic to Your System
There are two types of sunscreen, physical and chemical. Physical sunscreens sit on top of your skin and reflect the sun’s rays. Chemical sunscreens are absorbed into your skin where they absorb the sun’s rays, sort of like a filter.
Physical sunscreens are made from titanium and zinc. They used to have a pasty texture that left a white film on your skin, but producers have greatly improved the look and feel of these sunscreens by using smaller particles of the active ingredients. When the new and improved versions came out, some people feared that the zinc and titanium nanoparticles could get absorbed into your body and wreak toxic havoc.
In 2017, the Therapeutic Goods Administration published a review on all of the evidence available on zinc and titanium nanoparticles1. They determined that these particles do not get absorbed into your body and are safe for use in sunscreen.
In Conclusion; Zinc and titanium nanoparticles in sunscreen do not enter your system and are safe for human use.
The Ingredients in Sunscreen Cause Cancer
As noted above, there are two different types of sunscreen, physical and chemical, and the evidence suggests that they are both safe for human use.
Chemical sunscreens contain active ingredients that can be absorbed into your system, but they are still considered safe for human health. Our bodies have a method of flushing these ingredients out when they are absorbed. A few studies have found evidence of oxybenzone (a common ingredient in chemical sunscreens) in urine, but they did not find a link between its presence and adverse health outcomes2. The Therapeutic Goods Administration considers sunscreens with up to 10% oxybenzone to be safe3.
Some chemical sunscreens may contain phenols or parabens that are absorbed into your skin. These are common in many personal care products including sunscreen, shampoo, deodorant and bodywash. They can act like hormones in the body and some studies have linked parabens to breast cancer, but research into this is ongoing. If you’re concerned about parabens, you can buy sunscreen and many other products that are paraben-free.
In Conclusion; The active ingredients in sunscreen do not appear to cause cancer.
Sunscreen Affects Your Hormones
As mentioned above, most personal care products contain parabens and phenols, and this includes some chemical sunscreens.
Parabens and phenols are sometimes called “endocrine disrupters” because they can act like hormones if they enter the body. This does not mean that all sunscreens contain parabens and phenols, nor does it mean that sunscreen directly affects your hormones (the evidence reviews cited above found no evidence between the presence of phenols from sunscreen and physical hormonal outcomes4).
There is ongoing research on the effects of phenols and parabens, and some potentially worrysome effects that are still being investigated by the scientific community. The good news, as mentioned above, is that you can mitigate any potential risk by choosing sunscreens (and other personal care products) that are paraben and phenol-free. Additionally, if you use a physical sunscreen instead of a chemical sunscreen, you don’t absorb the active ingredients into your skin.
In Conclusion; Sunscreen does not disrupt your hormones.
Sunscreen Causes Cancer Because It Doesn’t Protect You Well Enough
An oft-cited study from Sweden in the year 2000 found that regular sunscreen users had higher rates of melanoma, but the researchers themselves concluded that this was likely because sunscreen-users spent much more time in the sun5. Contrary to this, four trials presented at the National Sunscreen Summit in Brisbane in 2018 found that daily sunscreen use protected the skin from UVB damage and it helped prevent abnormal tissue growth associated with skin cancer6.
The risk related to this rumour probably has more to do with our understanding of sunscreen than with the sunscreen itself. Sunscreen provides protection from UV rays, but it does not give you a pass to spend all day in the sun. To reduce your risk of skin cancer, you need to reapply sunscreen regularly (and especially after swimming, sweating or towelling). Additionally, you should always partner sunscreen with a hat, sunglasses, protective clothing and sitting in the shade when possible. Sunscreen does not guarantee 100% all-day protection no matter how high the SPF.
In Conclusion; Sunscreen prevents skin cancer when used properly as directed. It does not cause skin cancer.
Sunscreen is Bad for the Environment
Unfortunately, this one might be true. A 2015 report on the effects of chemical sunscreen ingredients on aquatic life was so compelling that the state of Hawaii legally banned sunscreens containing oxybenzone and octinoxate7. Basically, these two ingredients are toxic to algae that gives coral its colour and life. Without this algae, the coral bleaches and dies.
Most of the research on how sunscreen affects coral reefs has focussed on the active ingredients found in chemical sunscreen. There is not much research on the environmental effects caused by active ingredients found in physical sunscreens (zinc and titanium). The little bit of research conducted did find that zinc has adverse effects on coral, but it was conducted in a laboratory with very high levels of zinc. Further research is needed on this concern8.
Research is also being conducted in search of a more environmentally-friendly sunscreen, and we will post here on our blog and social media channels as soon as one becomes available.
In conclusion; Chemical sunscreens are bad for coral reefs. Physical sunscreen may also be detrimental, but more research is needed to confirm.
We live in a world where information flies like wildfire. Be sure to always take a critical look at the evidence and where it comes from. If you have any further confusion or concerns, you can always come in and speak to our Skin Cancer Doctor.