Ook interessant. Nu zeg ik niet meteen dat het superlekker spul is of dat je het elke dag moet gebruiken, maar je hoeft ook niet meteen in paniek te raken. Is my sunscreen going to kill me? Perform a search on sunscreen safety and some scary stuff shows up! Retinyl palmitate causes skin cancer. Oxybenzone causes estrogen-like effects on the body. I have seen these statements repeated over and over again all over social media and in real life. I recently heard from a patient, “I was using Neutrogena but then stopped because I heard it wasn’t so good for you.” How do we protect ourselves and our families from skin cancer without any nasty side effects? Photo credit: Shutterstock I’d like to offer up my take — from a organic-loving, Whole-Foods-shopping, yoga-practicing, green-tea-drinking MD (dermatologist), with an eye for interpreting both media and science… For those not able to read the whole post (we are all busy, I know!), here’s the quick summary of my findings. You can read on for more info too! Sunscreen won’t cause hormonal disruption — it would take 200 years of application to even reach questionable levels of exposure. Sunscreen won’t cause skin cancer — the use of sunscreen is directly correlated to the prevention of skin cancer. Retinyl palmitate is an anti-oxidant that occurs naturally in the skin. Nanosize sunscreens are safe for use, as they clump in real life, preventing them from being absorbed. I’ve researched the issues of sunscreen safety personally, and WOW! It’s confusing and contradictory. I’ll at least say this— we always need to critically and scientifically analyze the sunscreen ingredients we use for both efficacy and safety. And just as important, let’s not perpetuate myths that are based on unsound science. If you are interested in sorting through the muddy waters of sunscreen information — read on! Environmental Working Group’s Rankings of Sunscreens. Most of the information about safety stems from the Environmental Working Group’s sunscreen rankings. The Environmental Working Group is a not-for-profit organization that searches to identify harmful chemicals in our environment. While I applaud the intentions of the EWG to find safe and environmentally responsible materials, we need to be fair and look at these issues seriously, and not just solely how presented by the EWG. Do sunscreens cause hormonal disruption? The EWG advises avoiding any products with oxybenzone (an excellent UVA and UVB blocker) as it may cause effects similar to estrogen. The concern comes from a study performed in rats, where the rats were fed supratherapeutic doses of sunscreen (let me say that again, the rats ATE sunscreen at megadoses), and the size of their uterus enlarged. Edited graph from PMID 11333184 There is a monstrous difference between eating super high doses of sunscreen and applying it to your skin daily — and concluding that topical use in human sunscreen causes estrogenic effects is an unrealistic stretch. A study in 2011 in JAMA Dermatologyshowed that it would take 200 years of daily sunscreen application to reach the same amount of exposure as the rats in this study. To the author’s credit, their word-for-word conclusion in the abstract was: “Our findings indicate that UV screens should be tested for endocrine activity...” The authors do not say that the UV screens cause hormone activity in humans… they can’t. In order to substantiate their EWG’s claim, you would need to show hormone disruption in real live humans. Luckily, such a study was performed. Human patients applied more than 3 times the real-life quantity of a high percentage oxybenzone sunscreen (10% oxybenzone, compared to the commercially available 6% oxybenzone) to their whole body daily for one week. Oxybenzone was in fact detected in the urine of the volunteers (as have some other sunscreen agents). Sound the alarm bells! — this is concerning. It indicates that there is some absorption from topical use (medications that are applied directly to the surface of the skin). However, the body quickly excreted it through the urine (which is a good thing). Much can be said about the fact that it was absorbed, but the take-home message was that the researchers were UNABLE to show a hormone disruption despite this absorption (again, this was at 3 times real-life dosage). There was no accumulation of the ingredients over time. So we have a study in humans of real-life sunscreen use that shows no hormonal effect, or a study where rats ate sunscreen — which do you believe? To be fair, when researching this blog post, I did come across an alarming number of lab and animal studies showing absorption of various sunscreen agents, with some experiments suggesting hormonal disruption. There were almost as many studies that showed no absorption nor hormone disruption. A good summary of those studies can be found here. But we have to look at what’s important… no human studies have shown hormonal disruption, and that is what counts. Of note, it is important to mention that oxybenzone can cause allergic skin reaction in a fair percentage of people, so there should be some caution with its use. And by the way, soy is weakly estrogenic. Where are the cries for banning or avoiding soy milk because of hormonal activity? There are many natural skin care products on the market containing soy, several of which I recommend and are excellent. A little perspective is important, and we need to remember that topical use is very different from ingestion.
@suus1983 , heel mooi dat je dit even zo hebt opgezocht Ik zag deze laatst ook al voorbij komen. Ik denk dat de notitie weer moet worden gemaakt niks is goed voor je als je het niet gebruikt zoals je het zou moeten gebruiken. En we moeten elkaar ook echt niet meer bang gaan maken van alleen dat kopen dat ga je toch niet smeren etc. Dan moeten we denk ik maar in een bubbel afgesloten van de wereld gaan leven.