Proprietary Blends

A proprietary blend lists several ingredients under one name with one combined weight. It can appear on products that mix several adaptogens or add other ingredients. The label tells you the total, but not how much of each ingredient is inside. That makes it hard to compare a product with the amounts used in studies, or to check an ingredient you are cautious about. "Adaptogen" is a contested term, so a blend labeled that way is not evidence of any benefit.

What the US label rules require

The FDA labeling guide (page dated 2005 as read) and the current federal regulation (21 CFR 101.36) say the following:

• The blend is identified by the term "Proprietary Blend" or another descriptive or fanciful name. [1][2]
• The total weight of all the "other dietary ingredients" in the blend is shown on the same line. [1]
• The ingredients are listed underneath in descending order of predominance by weight. [1]
• Dietary ingredients that have a reference intake (an RDI or DRV) must be listed separately with their individual weights. [1]

A 2023 paper in the Journal of Nutrition says the law lets companies list non-nutrient ingredients as blends "to protect their unique formulas," and that the blend's weight and ingredient names must be declared, but not the amount of each ingredient. [3]

What the label does and does not tell you

The 2023 paper puts the research problem plainly: from label information, the amount of an ingredient in a proprietary blend is not available for calculating exposures in assessments of intakes, or for determining doses in clinical trials. [3]

An illustration (invented numbers, not a real product)

Imagine a label that reads "Adaptogen Blend, 500 mg: ashwagandha extract, rhodiola extract, ginseng extract." By the ordering rule, the first ingredient weighs at least as much as the second, and the second at least as much as the third. The third could be a few milligrams or as much as about a third of the total. The label cannot say which. This is simple arithmetic from the rule, not a finding about any actual product.

Why this matters for adaptogens

• Trials use specific amounts of specific extracts. Results for one extract or amount do not transfer to another. A blend's total weight is not an amount of any one extract. See what clinical studies say about amounts and single adaptogens versus blends.
• Cautions follow the ingredient. Several adaptogens have documented cautions with certain medicines or conditions, covered on the adaptogen safety page. In a blend you cannot see how much of the ingredient of concern you are getting.
• Duplicates are hard to spot. Two products may contain the same ingredient. See amounts and duplicate ingredients.
• Quality checks are harder. If a laboratory tests a finished blend, the ingredient amounts it finds need a declared amount to compare with. The sources we read do not describe how often adaptogen blends are tested this way.

Proper evidence not found: we searched PubMed for proprietary blend and dietary supplement label-amount studies and did not find a study measuring the actual ingredient amounts in adaptogen blends against their labels, or one comparing blends with single-ingredient products. The 2023 paper is a perspective on label disclosure, not a measurement of product contents.

What a reader can do

• Read the full label, including the plant part for each ingredient (see reading an adaptogen label).
• The FDA suggests you can contact the manufacturer for information about a product. [4] Asking for the per-ingredient amounts is a reasonable question; whether a company will answer is not described in the sources we read.
• Ask a pharmacist or clinician to review the ingredient list against your medicines, especially if you are pregnant, breastfeeding, have a thyroid, liver or kidney condition, or have surgery coming up. NIH says supplements may interact with medicines or pose risks around surgery. [5]
• For a general framework, see how to evaluate a supplement formula and proprietary blends and hidden amounts.

Mushroom and "functional" coffee or drink blends raise the same question; see mushroom coffee and adaptogen blends, claims checked.