“Feed your cells,” says Centrum. “Designed with your genetics in mind,” says Ritual. “The perfect women’s multi,” says Olly. “All clean, all the time,” says Sundown. “We’re so organic,” says VitaFusion. Companies use any pitch that works to sell their multivitamins. But they dodge the $64,000 question: Do you need one? The short answer: We don’t know.