Are all retinols and, indeed, every form of vitamin A to be avoided in all daytime skin care products because they can cause cancer? This scary question was prompted by Truth In Aging community member Sonya, who wrote to me saying that she had read on the Environmental Working Group (EWG) website that all forms of vitamin A become carcinogenic when exposed to sun. With so many products containing vitamin A, retinol and other derivatives, this would mean, Sonya added, that she needed to strike off just about everything on her beauty wish list.
The implications of her question are so important that I decided to look at the EWG’s position and do some research of my own. Here’s what I found.
What is vitamin A?
First a quick reprise on the vitamin A family. Vitamin A includes a family of ingredients that are popular with anti-aging and anti-acne formulators. Retinyl palmitate is the ester of retinol (vitamin A) and it is combined with palmitic acid, which is a saturated fatty acid. Retinol is Vitamin A in its whole molecule form, which can be broken down into thousands of smaller components, including retinoic acid (or Tretinoin, the active ingredient in Renova and Retin-A).
Retinyl palmitate and cancer
In 2009, the FDA started gathering evidence of possible links between retinyl palmitate (RP) and cancer and, specifically, how RP reacts with sunlight. Back in 2005 and 2006, the National Center for Toxicological Research had concluded that RP was photomutagenic and could cause free radical damage when exposed to UV light (more details here).
In 2010, the EWG and Senator Charles Schumer started to push the FDA to release its findings. EWG issued press releases calling on the FDA to act on the grounds that RP is a common sunscreen ingredient.
In 2011, the National Toxicology Program issued a report based on a year-long study on mice that concluded that retinyl palmitate became carcinogenic in sunlight (more details here). The EWG responded with a statement asking the cosmetics industry to stop using this ingredient in products likely to be exposed to the sun and urging consumers to “avoid buying products that contain this chemical.“
The EWG position on vitamin A
Now, I was well aware of EWG’s position on retinyl palmitate and TIA has been covering the issue over the years. Until Sonya contacted me I hadn’t realized that a broader decision had been taken since 2011 against all forms of vitamin A. This position is laid out in its report The Problem with Vitamin A, where the EWG says: “consumers [should] avoid sunscreens and other skin and lip products containing vitamin A, retinyl palmitate, retinol, retinyl acetate, retinyl linoleate, and retinoic acid.”
The EWG explains that its position is based on concerns in Germany and Norway about excessive vitamin A intake. So, naturally, I decided to take a look at what the Germans and Norwegians had been saying. And this is where things aren’t quite as clear cut.
The German concern is based on foods artificially enriched with vitamin A and supplements. Together these account for about 60% of what is considered the safe upper limit before there could be an adverse impact on bone density. As an aside, it is worth noting that in normal foods that have not been artificially enriched, liver is the best source of vitamin A and in reasonable quantities, it does good things for immune system, vision, and cellular communication (source). Anyway, the Germans thought that vitamin A in cosmetics could add 25%, so the intake if someone was also eating a lot of vitamin A enriched food or taking supplements could be 85% of the safe upper limit.
In Norway, the issue was around skin irritation and it was this concern that led to national restrictions on use. However, in 2013, Norway concluded that the data was insufficient to recommend an upper concentration limit (source) and the Norwegian restrictions were dropped in line with new Europe-wide legislation.
The industry position
Sonya wanted to know what the brands that formulate with retinol such as Dr. Dennis Gross would say to all of this. I haven’t asked Dr G directly, but the formal position of the American Association of Dermatology (AAD) is that there is “no evidence that the inclusion of retinyl palmitate in sunscreens can cause cancer in humans.” This is based on three things: (1) the studies were conducted on animals (mice), not humans; (2) mice 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”; (3) in the studies retinyl palmitate was used on its own, not with other antioxidants.
My take
First, there seems to be enough evidence that retinyl palmitate reacts to UV light to cause free radical damage to justify caution. I would not purchase a sunscreen containing this ingredient and I would be sure to use a sunscreen if I was using a skin product that contained this ingredient.
This is unlikely though, since I am careful about the amount of retinols (and derivatives) in my skin care. I do not think I should ban these ingredients completely as the EWG suggests, but I am cautious about using them. For example, I have been using Dr. Dennis Gross Ferulic & Retinol Fortifying Neck Emulsion ($75 in the shop), which has retinol. Because I am concerned about retinol making my skin more sun sensitive, over-exfoliated or irritated, I would not use more than one retinol, product at a time and I would slow down use of the DGG neck cream once it has had an effect and alternate with a non-retinol product. So I guess I am with the Norwegians in thinking that, as a potential irritant, retinols and derivatives are best used with limitations.
I am not especially concerned about vitamin A toxicity due to excess from a combination of diet and skin care. This German concern seems more than a little speculative. It’s pretty hard to OD on vitamin A from unprocessed food — unless one were to gorge on polar bear liver. I don’t eat processed foods such as cereals or energy bars that have been vitamin fortified — if I did, it would be worth noting that a cup of Kellog’s Raisin Bran has 20% of my daily vitamin A needs.
The EWG is a well-intentioned and necessary watchdog. However, in this case it has taken research evidence on a specific form of vitamin A, and European concerns about irritation and processed food to propose a complete ban on all forms of vitamin A in all skin care products. I think this misleading and unhelpful based on the evidence available.
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