In general, an eyelash-growth claim "would indicate an intent to affect the structure or function of the body, and thus, cause the product to be a drug, " which would require FDA approval, says Shelly Burgess, a spokeswoman.

WSJ: Aches & Claims: Another Wand for When Mascara Isn't Enough

But the Food and Drug Administration does not prospectively review food claims because American law says that foods are allowed to affect the "structure and function" of the body, so long as they do not actually claim to treat disease.

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