A Mysterious Case of Vitamin C in Skincare. Can Plant Based Oils Contain Vitamin C?
My quest to understand the polar comments concerning vitamin C in oil based products began when I noticed a few brands and handcrafters touting their products as rich in vitamin C because they contained rosehip oil or strawberry seed oil.
Yes rosehips and strawberries are a good source of vitamin C but ascorbic acid -- aka vitamin C is water soluble so how then could it show up in the oil?
As a cosmetic formulator I've completed two programs taught by cosmetic chemists, one program geared towards organic formulations skills, and at present am working through a program taught by a woman who began as a medicinal herbalist making personal care products who was later trained in cosmetic chemistry.
I'm a meta-analysis kind of gal. My educational roots are in science, biology, molecular biology, cancer and cardiovascular research, aromatherapy, and cosmetic science. It's a strange road perhaps but I like to investigate, ask questions, and understand. And I believe that meta-learning helps me better understand the world around me and think outside the conventional.
So a lovely handcrafted brand I noticed on a platform that promotes handcrafted products touted their strawberry oil based vitamin C oil serum. They noted all the benefits of vitamin C that their oil based serum would provide like skin brightening, smoothing wrinkles, promoting collagen production, protect against sun damage, and so on.
Well it turns out that ascorbic acid isn't the only vitamin C game in town. There are some oil soluble versions of vitamin C such as ascorbyl palmitate or ascorbyl linoleate but do they naturally show up in oils derived from vitamin C rich plants?
I dug into a research article that explored the vitamin C content of rosehip seed and seed oil and it indicated that ascorbic acid was present in the seed but not the oil. (1)
Makes sense but is it possible that the oil soluble versions of vitamin C are showing up in the oil or are they only a product created in the laboratory?
As I researched some more it wasn't clear if these types of vitamin C were occuring naturally in the seed oils or not. But what is clear if something isn't measured, documented, or quantified we can't guess or make claims that it is actually there.
Yes rose hip oil or strawberry seed oil or the like may be a beautiful part of a serum, a facial moisturizer, a skincare or haircare product but without knowing the actual composition or typical profile of the oil one can't make claims.
Carrier oils often have typical fatty acid and oil soluble vitamin profiles that provide a range of what to expect in a particular carrier oil. Similarly essential oil often have a "typical" chemical profile and batches may specific data about the chemistry.
But if one does not have data that clearly indicates the levels of a particular compound in an ingredient how can one know? It's only a guess.
So although carrier oils such as rose hip seed or strawberry seed oil do come from plant parts rich in vitamin C, oils are NOT typically a rich source of vitamin C. And unless you have test data verifying the content of vitamin C in an ingredient or you've added a vitamin C active to a formula in amounts that have been shown by research to produce results and in a form that is able to be incorporated into the formulation base you shouldn't claim what you cannot quantify and back up with data.
Yes rose hip seed oil and strawberry seed oil are beautiful carrier oils and they can help support skin health and moisturization, but making claims about vitamin C content and its benefits is definitely a stretch.
If you really want to create an oil based C-serum that includes rose hip or strawberry seed oil adding an oil soluble vitamin C in an amount that has been clinically shown to create the desired results is the only way you can actually be sure that your product will have a chance to deliver what the product promises.
What are your thoughts?
Huri Ilyasoğlu(2014)Characterization of Rosehip (Rosa canina L.) Seed and Seed Oil,International Journal of Food Properties,17:7,1591-1598,DOI: 10.1080/10942912.2013.777075