The One Ingredient in Sunscreen to Avoid
Okay, so this title may be misleading because there are a number of ingredients in sunscreen that make my head spin and green pea soup-y stuff shoot out of my mouth. But if you find a sunscreen without this one ingredient, you are likely putting something on your skin that doesn't include a lot of the other junk either.
So here it is. The one ingredient I want you to watch out for. You may have to squint to find it...
Here's why I want you to avoid it...
The Environmental Working Group (EWG) has posted warnings about this ingredient for years, claiming that it's a potential hormone disruptor and, and here is the kicker, becomes carcinogenic when exposed to sunlight.
Yes, a major ingredient used in SUNSCREEN has been shown to potentially cause cancer when you expose it to sunlight.
But let me back up a bit.
You know I like to research.And I want to make sure there is science behind these kind of claims before I share them with you because we all have enough to be thinking about already and Good Grace don't give us something else.
Retinyl palmitate is composed of palmytic acid and retinol, one of the animal forms of Vitamin A. All retinoid forms of Vitamin A are used in cosmetics. Retinoic acid is used in the treatment of severe acne, as in Accutane. Vitamin A is thought to be a powerful antioxidant and as such, may protect against cancer and help to fight the aging process.
Which is why it's often used in sunscreen. Makes sense, right?
Except that when we start extracting vitamins and changing their make-up and ingesting them in ways that nature may not have intended (as within sunscreen), sometimes we change how our bodies react to them.
The Skin Cancer Foundation put out a statement, specifically referring to the EWG and how its claims about sunscreen were based on "junk science". Usually when I refer to anything by the EWG, the data they present appears to be well-researched and includes a number of references, so I was surprised that the SCF would make this claim.
So I looked into why they might.
Turns out the SCF has a number of corporate sponsors, which you can find here. They include big names like Proctor & Gamble, Neutrogena, Banana Boat, Hawaiian Tropic, and a whole bunch more. It was the same with the American Academy of Dermatology, which also posted a paper blasting the EWG and their warnings. You can see the corporate partners for the AAD here.
So if my choice is to believe an organization that was founded to make access to information about what we put into our bodies easier or to believe one that is funded by the very manufacturers who stand to benefit by keeping things as is, I tend to lean toward the former. Oh, and the EWG has corporate partners as well. You can read who they are here.
Okay, but let's get back to the science. I wanted to be sure there was, indeed, science.
This study was published in March of 2010 by Toxicology in Vitro. It found that mouse lymphoma cells treated with retinol did not increase genetic mutations. Once exposed to UV light, however, the oxidation process and subsequent genetic mutations began, in a dose-responsive manner, which means the more UV light, the more genetic mutations there were.
"These results suggest that retinol is mutagenic when exposed to UVA in mouse lymphoma cells through a clastogenic mode-of-action."
This abstract refers to a couple different studies that found tumor activity in hairless, albino mice increased when topical tretinoin (the retinol version used in acne medications) was combined with ultraviolet light. More studies are being done because similar types of medication have been found to be very effective against severe psoriasis.
This study, published in the International Journal of Environmental Research and Public Health in 2006, found that "similar to irradiation with UVA light, RP can act as a photosensitizer leading to free radical formation and induction of lipid peroxidation following irradiation with UVB light". Lipid peroxidation is when cells get damaged, making them more susceptible to cancer.
In the same journal, one year before, this was the conclusion to a paper...
"Regarding human toxicity, the long-term consequences of using cosmetics containing RP are currently unknown. It has been demonstrated that photoirradiation of RP can result in forming toxic photodecomposition products, generate ROS, induce lipid peroxidation, and cause DNA damage. Also, topically applied RP produces many of the cutaneous changes associated with the use of drug products containing RA which in some instances can enhance photocarcinogenesis. Thus, a study of the photocarcinogenesis of RP, under conditions relevant to the use of RP in cosmetics, is timely and important. As a consequence, RP has recently been nominated by the U.S. FDA and selected by the National Toxicology Program (NTP) as a high priority compound for phototoxicity and photocarcinogenicity studies. The goal of these studies is to provide relevant information necessary for risk assessment of RP in cosmetic creams."
To my knowledge, the study of RP has NOT become a "high priority" in any sense. I suspect if it had been in the past decade, we may have seen it removed as an ingredient in sunscreen. The problem with trying to prove a product is carcinogenic is that you can only do it in a lab. It is considered unethical to test carcinogenicity on humans, and to use observational studies on the rates of cancer among sunscreen users would be difficult as well. Was the cancer caused by the sun or by the sunscreen? What other lifestyle factors could have contributed to the cancer?
The industry likes to argue that there are no "definitive" studies, which is true. We are forced to make the best choices based on the information we DO have.
I will keep looking into this but it's beach season and I want you to be safe. Below are some of the top sunscreens the EWG recommends as safe. For a complete guide, check here.
Ava Anderson (must get through a rep)