Proprietary blends: when the label hides the amounts

Two labels can list the same three ingredients and the same total weight – and only one of them tells you how much of each is inside. The other calls it a “proprietary blend”. It’s legal, it’s common in some kinds of supplements, and it makes the price per dose impossible to check.

Same ingredients, two labels

Both of these made-up labels add up to 9.4 g. Only one tells you what’s in it:

What the rules allow

The FDA lets makers group ingredients under one name – often something like “Performance Matrix” or “Energy Complex”. The label has to show the total weight of the blend and list its ingredients from most to least by weight (FDA (opens in a new tab)). Vitamins and minerals with a Daily Value still need their own amounts – blends are mostly herbs, amino acids, enzymes and other ingredients without one.

Where blends are most common

1,151

products with a proprietary blend, out of 16,088 labels

83

different supplements where we found at least one

Blends cluster where a product mixes many things: enzymes, greens powders, multivitamins, mushroom mixes. Pre-workouts are known for them, but only 10% of the 231 we checked have one, and 9% of protein powders.

Why it matters for the price

Our price lists compare the cost of one ingredient in a fixed amount – for example 6 g of citrulline. With a blend, the amount of each ingredient is unknown, so that price can’t be worked out. For mixed products like multivitamins and greens powders, we compare per serving instead – a blend doesn’t change that number, but it hides what you get for it.

In our quality score, a blend costs 15 of the 20 points for showing every amount. It’s not a judgment on what’s inside – only on what the label lets you check.