If you've spent any time comparing supplement labels, you've seen the phrase "Proprietary Blend" followed by a single number and a list of ingredients. Here's what that actually means, and doesn't.
Why Companies Use Proprietary Blends
The most commonly cited reason is protecting a formula from competitors copying the exact ratio of ingredients. That's a legitimate business concern — but it comes at a direct cost to the consumer's ability to evaluate the product.
What You Genuinely Can't Know
With a proprietary blend, you know the combined weight of all listed ingredients together, but not how that weight is distributed. A blend could be 90% one cheap, high-volume ingredient and 10% total for the remaining nine — all legally accurate, with nothing on the label to tell you otherwise.
The "Fairy Dusting" Problem
Industry critics use the term "fairy dusting" to describe including a research-backed ingredient at a trace, clinically meaningless amount specifically so it can appear on the ingredient list — a practice that proprietary blends make essentially undetectable from the outside.
Is a Proprietary Blend Ever Reasonable?
Some legitimate brands use blends for genuinely proprietary ratios developed through real formulation work — the existence of a blend alone isn't proof of a bad-faith product. But it does mean you're being asked to trust the brand's claims about efficacy without a way to independently verify the dosing behind them.
The Alternative
Full disclosure — listing every active ingredient with its individual amount — gives up the "ratio protection" argument in exchange for letting the customer actually evaluate the product against published research. It's a real tradeoff, and one that transparency-focused brands make deliberately.