“Bioavailability” is the term used by scientists to describe how much glycolic acid is available in a topical cream to permeate the stratum corneum or the outer layer of your skin. “The bioavailability of glycolic acid in a topical formulation is the fraction of glycolic acid that can permeate the stratum corneum of the skin”. (Source Cosmetic Dermatology) “Bioavailability” is also sometimes referred to as “free acid value”.
The term “bioavailability” defines the point of difference between pH ADVANTAGE and other brands. The pH ADVANTAGE Regimens deliver more glycolic acid to the skin due to their unique formulation with a lower pH (bioavailability) and, as a result, they are the most effective glycolic acid products sold in retail today.
In order for you to know how much glycolic acid is actually in a product, you need to know the amount when it is being prepared for processing (we call this the “initial concentration”) and what the pH level is when the processing is completed. If you do not have that information you will not have any idea how effective the product will be. The pH ADVANTAGE glycolic acid products always indicate on the front of the package the pH level, the initial concentration and the bioavailability so that you always know what you are getting.
Remember, the higher the initial concentration and the lower the pH level of a product, the more effective the glycolic acid product will be. For example, in the pH ADVANTAGE AM MOISTURIZER in Regimen 1, the initial concentration of glycolic acid is 7% and the pH level is 3 which means that 5.74% of the glycolic acid (round to 6%) is available to penetrate the stratum corneum. If the pH level of that product were 4.5, the amount of glycolic acid available to penetrate the stratum corneum would be only 1%, hardly enough to do anything at all for your skin. These calculations are based on the Henderson-Hasselbach Equation (Source: Cosmetic Dermatology). Because the pH scale is logarithmic, a difference of one pH unit represents a tenfold or ten times change. As an analogy, earthquakes with magnitudes of between 2.5 to 5.4 only cause minor damage while earthquakes with magnitudes of between 7.0 to 7.9 are considered major and cause severe damage (Source: UPSeis), very similar to the logarithmic scale of pH.
It is important to note that most glycolic acid products in the retail market have pH levels of between 4 and 4.5. On the next page you will see a chart that illustrates the pH scale for glycolic acid products based on the Henderson-Hasselbach Equation. It shows how products with initial concentrations of 7% and 11% respectively can vary in effectiveness depending on the pH level of the product. For example, the pH level of 3 (highlighted on the chart) represents the pH levels of all pH ADVANTAGE glycolic acid products and indicates the “bioavailability” of the products with initial concentrations 7% and 11%. Further down the chart you can see what the “bioavailability” of those products would be if the pH levels were 4.0 and 4.5. Quite a difference!
The term “bioavailability” defines the point of difference between pH ADVANTAGE and other brands. The pH ADVANTAGE Regimens deliver more glycolic acid to the skin due to their unique formulation with a lower pH (bioavailability) and, as a result, they are the most effective glycolic acid products sold in retail today.
In order for you to know how much glycolic acid is actually in a product, you need to know the amount when it is being prepared for processing (we call this the “initial concentration”) and what the pH level is when the processing is completed. If you do not have that information you will not have any idea how effective the product will be. The pH ADVANTAGE glycolic acid products always indicate on the front of the package the pH level, the initial concentration and the bioavailability so that you always know what you are getting.
Remember, the higher the initial concentration and the lower the pH level of a product, the more effective the glycolic acid product will be. For example, in the pH ADVANTAGE AM MOISTURIZER in Regimen 1, the initial concentration of glycolic acid is 7% and the pH level is 3 which means that 5.74% of the glycolic acid (round to 6%) is available to penetrate the stratum corneum. If the pH level of that product were 4.5, the amount of glycolic acid available to penetrate the stratum corneum would be only 1%, hardly enough to do anything at all for your skin. These calculations are based on the Henderson-Hasselbach Equation (Source: Cosmetic Dermatology). Because the pH scale is logarithmic, a difference of one pH unit represents a tenfold or ten times change. As an analogy, earthquakes with magnitudes of between 2.5 to 5.4 only cause minor damage while earthquakes with magnitudes of between 7.0 to 7.9 are considered major and cause severe damage (Source: UPSeis), very similar to the logarithmic scale of pH.
It is important to note that most glycolic acid products in the retail market have pH levels of between 4 and 4.5. On the next page you will see a chart that illustrates the pH scale for glycolic acid products based on the Henderson-Hasselbach Equation. It shows how products with initial concentrations of 7% and 11% respectively can vary in effectiveness depending on the pH level of the product. For example, the pH level of 3 (highlighted on the chart) represents the pH levels of all pH ADVANTAGE glycolic acid products and indicates the “bioavailability” of the products with initial concentrations 7% and 11%. Further down the chart you can see what the “bioavailability” of those products would be if the pH levels were 4.0 and 4.5. Quite a difference!
