One of my must-have products, every single day, is a vitamin C serum. Vitamin C is a triple threat when it comes to optimizing your skin health: it brightens, firms, and fights free radical damage that can lead to accelerated signs of skin aging.
Over the past year, I’ve been using my vitamin C serum BOTH morning and night, and my skin is really loving it! This is new for me, because I finally have a vitamin C serum that doesn’t irritate my sensitive skin. So, let’s get to the good part: how can you level up your vitamin C serum to get the most out of it for your skin health?
1. Packaging matters. When it comes to your vitamin C serum’s stability and efficacy, look for high-performance packaging that uses an airless, opaque pump rather than a dropper. So many of my patients complain that their vitamin C serums start changing color about halfway through the bottle, and that’s because of a process called oxidation. Every time you open the dropper, the serum is exposed to oxygen thus prone to breaking down. Airless, opaque packaging helps to ensure that your product is just as potent from the first pump to the last pump because your formulation is not exposed to air, light, or other factors that can break it down.
2. The type of vitamin C being used matters. If you have sensitive skin or have found that vitamin C serums irritate your skin, it is likely due to the formulation. The classic, traditional form of vitamin C that’s been used in many formulations is called L-ascorbic acid. It has some serious pros, but one of the biggest downsides is that it is highly unstable and likes to break down. Heat, high pH, air, and sunlight can all contribute to breaking down L-ascorbic acid. So, L-ascorbic acid also has to be formulated at a low pH—specifically less than 3.5—in order to be stable and penetrate into the skin. For your reference, lemon juice, which I recommend that you add to your water, but that you don't apply to your skin because it's way too harsh, has a pH of 2. So, you can imagine that my patients who have sensitive or dry skin may experience stinging or sensitivity from using L-ascorbic acid due to its low pH. For these reasons, when it came to my own vitamin C Serum, Asta C Vitamin C Age Defense Serum, I chose to formulate it with 2 newer forms of vitamin C called tetrahexyldecyl ascorbate and 3-O-ethyl ascorbic acid. These are more stable and less irritating forms of vitamin C, which help to defend against free radicals, smooth, firm, and brighten the look of skin. We tested Asta C in rigorous clinical testing protocols, and 50% of our subjects had sensitive skin. They did not experience irritation, even using Asta C morning and night.
3. How often you use your vitamin C matters. If you’re using a non-irritating formulation and you've acclimated your skin to using a vitamin C serum by using it every morning for the first few weeks, you can work up to getting the most out of your vitamin C serum by using it morning AND night. Here’s how I do it now that my skin is adjusted to using vitamin C morning AND night:
With Asta C in particular, using it morning and night helps you get max benefits when it comes to defense against age-accelerating oxidative stress, brightening the look of skin, plus firming the appearance of skin. Here’s a video walking you through my recommended AM and PM skincare routine.
I love sharing info about my favorite skincare ingredients with you! You can learn more about Asta C Vitamin C Age Defense Serum and our clinical testing here.