Superfatting in soap: what the percentage tells you

You may have already seen a percentage for superfatting on a soap. This does not represent an additional care step during washing, but rather a decision in the formulation.

Simply explained

With a superfatted soap, less lye is used than would be mathematically necessary to completely saponify the fats used. This leaves some fat components unsaponified. In artisanal soapmaking, the term lye deficit is also used.

The stated percentage is usually a formulation value. It is not equivalent to an accurately measured amount of care oil that remains on your skin after rinsing.

Why the highest number does not automatically win

The oils used, the overall composition, and your washing habits also influence the result. A more highly superfatted soap does not have to be more pleasant for you than another. Furthermore, hair has different requirements than hands or body.

How this information helps you choose

Consider it as one piece of information among several. Read the area of application and the ingredient list. If a product does not state a number, it cannot be derived from the name or the lather.

And if your skin feels tight after washing: the solution is not necessarily a higher percentage. Pause using an uncomfortable product. If symptoms persist, seek professional advice. Our knowledge library helps you better classify product information, but does not replace individual advice.