“Clinically Proven.” “Breakthrough Technology.” “Ten Years of Genetic Research.” These are phrases you might expect to find in the pages of Scientific American. But these descriptions also show up in (commercials) and print ads for cosmetics.

Now a study finds that some—well, make that a lot—of those science-sounding claims are simply not true.

Researchers looked at nearly 300 ads in magazines such as Vogue. They analyzed claims in the ads and ranked them on a scale ranging from (acceptable) to outright lie. And they found that just 18 percent of the boasts that the researchers looked at were true. 23 percent were outright lies. And 42 percent were too vague to even classify. The study is in the Journal of Global Fashion Marketing.

The Food and Drug Administration (regulates) what goes into your cosmetics and what goes on the label. If a claim is blatantly untrue, the FDA can take action. Vague language on labels may be a way to keep the FDA at bay.

Meanwhile, ads are regulated by the Federal Trade Commission. Just last year they charged L’Oreal for deceptive advertising of its Génifique products, which the company said were “clinically proven” to boost genes’ activity that would lead to the production of proteins causing “visibly younger skin in just seven days.” A settlement (agreement) forced L’Oreal to back off on the claims.

So take those cosmetic ads with a grain of that salt scrub—after all, if scientists had really come up with a product that reversed your wrinkles or grew your eyelashes, it would sell itself.