With Vitamin C products – which are most effective?

With Vitamin C products - which are most effective?

Glad you asked this! This is a little hard to explain so hang in there with me. Stability is important but better quality Vitamin C products sold now are stable. Stability is not actually a measure of how well Vitamin C versions act in the skin as an antioxidant.


What is more important is how well the product protects your skin which depends on it being absorbed well into the skin and cells (bioavailability). As far as I know, no company has refuted the studies that showed that Vitamin C has the greatest antioxidant potential in skin when it is pHed to 3.5 and the concentration is about 15-20%.


Most Vitamin C esters in creams/lotions don’t meet those requirements. Also, L-ascorbic acid is harder to stabilize and that’s why it’s more expensive but it’s also easier to get a pH of 3.5 and the correct concentration. You’ll notice many companies market 10% or 15% but not 20%. At 20%, the preparations tend to be too irritating. Many with sensitive skin can’t use Vitamin C preparations at all.


In my opinion, companies try to confuse consumers with substandard products by marketing the product on stability when it’s not really the issue. Notice how they don’t talk about the pH or the concentration. Hope this makes sense.  Dr. I


Read Dr. Irwin’s article on Skincare Terms & Ingredients.


Learn about Dr. Irwin’s Skin Care Regimen.

Dr. Brandith Irwin, MD

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Hi, I’m Dr. Irwin, and I believe that consumers need and deserve a medically trained and unbiased skincare advocate.

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One of the best investments in your skin is your daily skincare. Why? Because you can prevent many problems with blotchy skin color, lack of glow, texture, some types of acne, and fine lines with good skincare products. You can also correct some of these problems with effective skincare products. Great skincare is often more expensive because quality ingredients are expensive. Some companies spend on research/development which benefits all of us and adds to the cost. Are they worth it? In general - yes!