We all know one: that friend who keeps their dresser stacked with vitamin bottles. They pop gummy pills religiously, judge those who don’t, and insist that their mother’s age-old advice – “take your vitamins!” -- is responsible for their glowing skin, luscious locks, and even high test grades.

Catherine Price, author of “Vitamania: Our Obsessive Quest for Nutritional Perfection,” would likely toss that friend an eye roll.

“Most of the things we take vitamins for don’t have much evidence behind them,” she says. “There isn’t convincing [research] showing that multivitamins will do much beyond healing serious deficiency diseases.”

It’s hard to believe this in an age when the standard commercial flight routine involves a full-out Airborne and EmergenC binge. Still, Price insists that we tune out the trend: America’s vitamin craze does little more than pad the pockets of our favorite supplement manufacturers.

“Vitamin C has not been shown to ward off colds,” Price says. In her view, the only mid-air magic being performed by Airborne is the Miracle of the Placebo Effect. “If you truly believe that Vitamin C will prevent you from being sick, then it might prevent you from being sick. But there is no substantial scientific evidence.”

Price doesn’t deny the power of nutritional vitamins – she notes that Vitamin C will cure scurvy, and a few squirts of Vitamin A can work miracles for the nutritionally blind.

But does that mean a healthy, well-fed person should be able to take triple that dose of Vitamin A and see like a mantis shrimp?? Well… not quite.

“We don’t fully understand what vitamins do in our bodies, or how much of each we need,” Price says. “We do know there is definitely a danger in taking excess amounts.”

Price is not alone – the NIH and Consumerlab have both expressed concerns about Americans consuming too many vitamins. So why does half the country take at least one multivitamin per day?

The real obsession can be traced back to the ‘90s, when the Dietary Supplement Health and Education Act passed. It ruled out any requirement that supplements – from Vitamin D to body building proteins to weight-loss pills – be tested for safety or efficacy. Price tells us this was passed after a tremendously expensive campaign by the supplement industry, with “lots of letter-writing and, frankly, misinformation.”

“It really set the scene for the modern medicine aisle,” she says.

Price suggests we might be over-thinking how much we really need additional vitamins. After all, they’re already in our favorite foods – and not just the leafy stuff.

“Donuts, cakes, and cookies are made with enriched flour,” she says, an ingredient packed with B vitamins and iron. “Most people can meet their vitamin needs by eating food, even if it’s not that healthy.”

For the millions of Americans with a cabinet full of chewable Dinos, though, Price offers one piece of advice:

“If you’re worried about getting adequate nutrients, look at your diet. Just make sure you get some orange juice once in a while.”