Journal · Clinical reading · 6 min
Concentration versus formulation: why numbers on labels mislead.
Vitamin C at 20% in a bad base delivers less to skin than vitamin C at 10% in a well-designed vehicle. The label does not tell you that.
The Biomedical Emporium® formulation desk
3 May 2026
The number a brand prints on the front of a bottle is a concentration by weight. It is not a promise of delivery. Delivery depends on the vehicle, on the pH, on stability, on how the packaging handles oxygen and light, and on the order of ingredients inside the formula.
A formulator's job is to work out how much of the labelled percentage actually reaches skin. That number is called bio-availability. It varies enormously. Two bottles with the same label percentage can deliver very different results, because one was engineered to protect the molecule and the other was engineered to fit a marketing slot.
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