From the FutureDerm Facebook page:

Futurederm, first thank you so much for all of your advice. I am a faithful reader of your blog and it has helped me out so much! I always used to go to the beauty aisle of drugstores and had a headache looking at all the products and their claims. Thank you so much for translating all of this and explaining the science!

After reading your entries, I do have a question for you. Is retinyl pal…mitate bad to use during the day (under a sunscreen)? I know you said to avoid retinol during the day, is RP just as bad?

Dear Priscilla,

I often say to avoid retinol during the day because it has been found that retinol makes the skin photosensitive, or more susceptible to sun damage. Retinyl palmitate also has this effect, although to less of an extent than retinol or other retinoids. However, in 2010, the Environmental Working Group reviewed results from the National Toxicology Program (NTP), and proposed retinyl palmitate in sunscreens may accelerate the risk of skin cancer. At the time, the Environmental Working Group demonstrated rats with tumors treated with retinyl palmitate-based sunscreen products developed skin cancer 11-21% faster than those not treated with retinyl palmitate.

Despite this, the retinyl palmitate-skin cancer link was recently disproven, in an August 2011 review Safety of retinyl palmitate in sunscreens: A critical study, published in the Journal of the American Academy of Dermatology. In the report, Dr. Steven Q. Wang, M.D., director of dermatologic surgery at Memorial-Sloan Kettering Cancer Center in New York, explains retinyl palmitate is safe and there is no evidence to prove retinyl palmitate increases the risk of skin cancer in humans.

In a nutshell, here is what caused all the confusion:

1. The NTP study looked only at rats, not humans.

“It is important to note that the mice in the NTP study are highly susceptible to the effects of UV radiation and can develop skin cancer or other skin abnormalities within weeks of UV exposure, even in the absence of retinyl palmitate,” said Dr. Wang. “That is why extreme caution is needed when extrapolating these animal study results to humans.”

2. The NTP examined isolates of retinyl palmitate, not networks of antioxidants in which retinyl palmitate is a component.

“Despite the concerns raised by these non-human studies, retinyl palmitate operates within the skin as only one component of a complex antioxidant network,” said Dr. Wang . “For example, when a sunscreen with retinyl palmitate is applied to the skin, a number of antioxidants work together to alleviate the risk of free radical formation seen in these in vitro experiments. If studied on its own – outside of this environment – its antioxidant properties can rapidly be exhausted, allowing the production of oxygen radicals. In these non-human studies, retinyl palmitate was the only compound studied – making the biological relevance of these findings to humans unclear.”

3. The National Toxicology Program tests thousands of common compounds, including aloe vera – and retinyl palmitate.

Many people hear that an ingredient is being tested by the National Toxicology Program (NTP), and naturally assume that the ingredient has the potential to be toxic – why else waste the time and resources? However, the NTP tests thousands of ingredients per year, selecting the most common, regardless of their potential to be toxic. For instance, aloe vera was selected last year. In 2010, 41 percent of sunscreens contained retinyl palmitate, which explains why the NTP tested it in the first place.

Bottom Line: Don’t be sucked into a culture of fear.

In order to be a smart consumer, you need to understand it is basic human psychology to be drawn to alarmist reports that warn us an ingredient is potentially harmful or toxic. Not only are we concerned for our families and our own well-being, but being attuned to danger has been ingrained in our biology over tens of thousands of years. For most of human existence, all we did was listen and prepare for – and run from – imminent danger.

However, being safe also means that we need to be skeptical at times. We are the most educated consumer culture in human history, and that means we have to stand guard at the gates of our minds, and accept everything at face value. I hate to think of how many people stopped using sunscreen – the most proven ingredient to fight against skin cancer! – because of the alarmist reports about retinyl palmitate. Tens of thousands of reports in the media, including on news channels, were published due to the report, and yet I have seen barely a hundred attuned to the safety review in the Journal of the American Academy of Dermatology.

So don’t believe everything you hear. Stay informed but remain skeptical. Trust your judgment, and don’t be afraid to ask questions from the experts. If there’s one thing I’ve learned as a blogger, it is how easy it is to reach top experts, dermatologists, business executives – you name it. Many people at the top of their game love to take the time to help others who don’t know, even if you’re not a part of the media. Some even make it a weekly or bi-weekly habit to reach out and answer e-mails or to return phone calls to help others. So ask. Be persistent. And stay informed with FutureDerm.com!

With that said, do you have a daily question? I’d be happy to research a topic in beauty+style for you! The best way is through Facebook or Twitter!

Photo source: Sunscreens, a photo by Jessica Wilzig on Flickr.