In the past few weeks, I have received letters from people terrified that their vitamin C serums are going to give them cancer. In some cases, a specific form of vitamin C called ascorbyl palmitate was singled out for concern, while other writers were on the verge of trashing anything in their medicine cabinet. Helpfully, everyone sent me some links so that I was able to see their sources. Since their concerns were shocking and the initial research seemed worrying, I set about trying to find out the truth about vitamin C and ascorbyl palmitate.
A study from 2002 on ascorbic acid-6-palmitate
All roads led back to a study from 2002 where the researchers (Meves et al.) set about looking at the antioxidant properties of a lipid-soluble derivative of ascorbic acid, ascorbic acid-6-palmitate.
Synonyms for this ingredient are ascorbate-6 palmitate, ascorbyl palmitate and vitamin C-palmitate.
What Meves found was that scorbic acid-6-palmitate strongly promoted ultraviolet-B-induced lipid peroxidation and they concluded that “despite its antioxidant properties, ascorbic acid-6-palmitate may intensify skin damage following physiologic doses of ultraviolet radiation” and noted that this was “probably” due to its “lipid component."
This does sound definitive, but is it?
Calls for more research
Not long after the 2002 Meves study, an article in the Journal of Investigative Dermatology, commented on it, noting “It is clear from the study reported by Meves et al that ascorbyl-6-palmitate is not ascorbic acid.” Then its author went on to question whether ascorbyl-6-palmitate could penetrate the stateum corneum or interefere with its own built-in form of antioxidant defense, disrupting the lipid barrier or even penetrate deeper and harm cellular layers of skin. The conclusion was “only additional in vivo studies will allow us to assess its potential harm to skin.”
So has there been more research?
The 2002 Meves study on the harmful effects of ascorbic acid-6-palmitate seems to be the only one its kind. I can find no other studies that try to replicate the results to either support or refute them. I went through the toxicology reports on PubMed and The Meves study is indeed listed there. But it is the only one that refers to harmful effects.
Research on ascorbyl palmitate is mostly positive. Actually, the research history is overwhelmingly positive. For example, a 2006 study on mice that demonstrated that ascorbyl palmitate topically administered twice a week inhibited 91% of tumors.
A study from 2014 found that this ingredient prevented cell death from X-rays. I’ll also mention research from 2013 on how ascrobyl-6-palmitate inhibited lipid peroxidation – the exact opposite conclusion from what got us started on this (although I do find it a bit odd that study was on humans and soybeans). In 2011, researchers noted that “vitamin C palmitate (VCP), a lipid-soluble form, integrates into human erythrocyte membranes and prevents oxidant damage”,
Other scientists (in 2013) have been cheerfully looking at ways to improve getting ascorbyl palmitate into the skin, seemingly unconcerned by the study from 2002.
One negative study from China concluded that ascorbyl palmitate had low antioxidant activity, which ascorbic acid’s was high.
I could go and on. As I said, the research pedigree for the safety of ascorbyl palmitate seems sound.
So why the sudden flurry of cancer concern?
The short answer is that I am not sure. However, a 2014 article by Felicia Rose Labs has been passed around.
The writer says that palmitate molecules “convert the skin loving vitamin C into a proven hazardous substance.” This process of stabilizing the vitamins leads to “accelerated skin cancer and skin aging.” This is entirely based on the Meves study from 2002.
She concludes that you should watch out for any vitamin with palmitate attached, including vitamin A. This is based on the National Toxicology Board’s findings that retinyl palmitate is carcinogenetic when exposed to sunlight. The thing is that the NTB also said that retinoic acid, not just retinyl palmitate increased skin lesions and photocarcinogenic activity.
Faced with only one, unreplicated study raising concerns and many more that find the effects on skin to be beneficial, I see no reason to stop using products with the ingredient ascorbyl palmitate.