I’ve mentioned my super-easy DIY vitamin C serum a few times before on social media, and some of you have been asking me for the recipe… but I’ve been so distracted with other things I never got around to posting it until now. I’m sorry! Please forgive me. I hope the results make up for my tardiness!
Here’s the video (you may need to disable AdBlock to see it) – scroll down for the recipe. Click here to watch on YouTube.
What Does Vitamin C Do in Skincare?
Vitamin C is a superstar anti-aging ingredient in skincare. It tackles anti-aging on lots of levels:
- Can increase collagen, which plumps up skin and decreases wrinkles
- Fades hyperpigmentation (brown marks like acne scars and sun spots)
- Acts as an antioxidant, protecting against free radical damage from UV, pollution and natural aging
Who wouldn’t want this, right? It does a bit of everything!
Related post: Antioxidants in Skincare: What Do They Do?
The Problem With Vitamin C
The big problem with using vitamin C in products is that L-ascorbic acid is very unstable in water-based products. It turns into yellow dehydroascorbic acid (DHA or DHAA) and other products very quickly: at pH 3.52 and 25 °C in amber glass, 50% is gone in a week. Luckily, DHA can convert back to L-ascorbic acid in your skin, and there’s no evidence that it’s bad for your skin (there’s actually a product with an accompanying non-peer-reviewed study that actually uses it as a way of getting vitamin C into your skin more easily). But there’s not a lot of evidence that it’s good either, and it degrades further into products that can’t be turned back into L-ascorbic acid.
Related post: Why Vitamin C Can Stain Your Skin (and How to Avoid It!)
L-Ascorbic acid can be stabilised by combining it with vitamin E and ferulic acid (plus it makes it work better). This is the approach used in serums from SkinCeuticals, Paula’s Choice, Timeless, Cosmetic Skin Solutions and Ausceuticals, However, if you want to DIY with this combo, it not only requires buying vitamin E and ferulic acid, but you’ll also have to get an emulsifier because vitamin E doesn’t play nicely with water.
And if you’ve gone to the trouble of mixing all that, you’ll also want a preservative to suppress bacterial growth so it’ll last longer and you won’t have to remake it any time soon. The price of all these ingredients adds up quickly, and if you’ve done any DIY before, you’ll know that you’ll end up with barely-used bottles that will go off before you finish them.
L-Ascorbic acid can also be stabilised by altering its chemical structure. Some derivatives of LAA include magnesium ascorbyl phosphate (MAP), and ascorbyl tetraisopalmitate (ATIP)/tetrahexyldecyl ascorbate (THDA). However, these are expensive compared to LAA, and they need to be converted back into LAA to work as effectively.
Related post: Mythbusting: Are Vitamin C Serums Bad for You?
The Solution: DIY Vitamin C Serum
All these issues can be solved by using a DIY vitamin C serum that you remake every week or so. I generally find DIY a bit of a pain – the minimum orders of the ingredients are too large for me to use up personally so I end up spending way more money than using a pre-made product, and there’s the horrible feeling of wastage when you chuck out expired, barely-used ingredients.
There’s also the time required to cook up your product, the failed batches, and the dreaded washing-up afterwards. But it’s hard to find a downside to this DIY serum:
- All the ingredients and materials are easy to get and inexpensive
- It takes about 5 minutes to make with no special equipment required
- It can be more effective than a store-bought product – you don’t have to deal with delivery times and distribution networks and having your vitamin C sit on a store shelf slowly degrading for an unknown period of time
- You can easily adjust the amount of vitamin C in your serum – add more LAA to ramp up the effectiveness, or use less LAA to decrease irritation
- It’s cheap enough that I don’t feel bad spraying it all over my face and chest and body
For an effective vitamin C serum, you need 5-20% LAA at a pH less than 3.5. Above 20%, the effectiveness of LAA doesn’t increase but the side effects (mostly irritation) do.