I’ve seen the term “proprietary blend” on the labels of dietary supplement products. What does that mean?
A “proprietary blend” on a dietary supplement’s Supplement Facts panel is a list of ingredients that are part of a product formula specific to a particular manufacturer. Manufacturers are required to list all of the ingredients in a product on its label, along with the amount of each (in terms of weight), unless the ingredients are part of a proprietary blend—then the specific amount of each individual ingredient in the blend does not have to be listed, only the total. So it is important to be aware that the exact amount of each ingredient in a proprietary blend (or blend or delivery system) is unknown. In fact, the only way to know what is in any particular dietary supplement product is through laboratory testing, which is why it is important to look for third-party certification.