Walk down any aisle in any grocery store and you won’t miss it: protein is everywhere. Packaging for everything from snacks to cereal boast that they’ve been stuffed with the muscle-building nutrient. There are seven grams in each serving of “Cheerios protein,” 10 in a Kind nut bar, and 15 in a small bag of something called a “protein chip.”

There’s no doubt we need the stuff—protein is one of the three macronutrients, along with carbohydrates and fats, that we get from our food. But of the three, protein is the only one that hasn’t been vilified by the media. Some of the most popular diets of the last decade, like Paleo and Atkins, encourage eating large amounts of protein while avoiding carbs. It’s been branded as the athlete’s nutrient and celebrated as a source of strength for those on the go.

Food companies have found a marketing opportunity. Realistically, though, the vast majority of us don’t need all that they’re selling—especially not in its powdered or otherwise supplemental form.

A market-made love affair

Protein powders didn’t used to exist—they’re the sort of end result of a long-developing fascination with muscular masculinity. Bodybuilding became popular in the 1920s in the US, and the common belief back then was muscle mass came from lifting weights alone, regardless of what you ate. But in the 1960s, Bob Hoffman, a war veteran, publisher of several health magazines, and weightlifter himself created a protein powder that used the dry remnants of soy after its oils had been extracted for grease and paints manufacturing. Shortly after, nutritionist Rheo Blair introduced protein powders made from dairy. These products tasted pretty bad and were a specialty item, sold mostly to male bodybuilders and actors trying to improve their physique.

Protein powders are the end result of a long-developing fascination with muscular masculinity

In the 1990s, protein supplementation hit the mainstream market. Dan Duchaine, a bodybuilder, created a powder from whey, a byproduct from making cheese. Around the same time, A. Scott Connolly, an anesthesiologist, founded MET-Rx. His company developed a powder that contained the same amino acid composition as breast milk, originally intended to help hospitalized patients recover from atrophied muscle. But they realized they could exponentially grow their reach by changing the marketing. Soon, MET-Rx powders were sold in convenient packets, designed so that anyone could quickly whip up a muscle-building shake—a direct appeal to those who wanted to bulk up or get toned.

Despite the fact that these products didn’t come with a clean sheet—Duchaine was one of the first vocal proponents for steroid use, and MET-Rx failed to produce peer-reviewed studies to back its body-transforming claims—protein took off. Today, it’s big business.

Globally, by 2017 consumers are estimated to spend over to $10.5 billion on protein supplements in the forms of bars, powders, and other mixes. More than ever, gyms are decorated with whirring blenders mixing mostly unnecessary protein smoothies for clients. According to Darren Seifer, a food and beverage industry analyst for NPD Group, a market research organization, “about 50% of adults” are typically looking for more protein in their food.

Show me the numbers

When nutritionists think about required nutrient intake, what they’re really considering is how much we need for our body to carry out its everyday functions. We don’t really need protein itself—what we get from protein, whether from meat or plant-based sources, are the 20 different amino-acids that contain nitrogen. “The way we determine [protein intake] is by a concept called the nitrogen balance,” says James Loomis, a physician with Barnard Medical Center in Washington, DC. “Our bodies can’t store nitrogen, like they do fat and sugar.” But we do need that nitrogen to build and repair cells, and signal between them—so, we’ve got to get it from food.

“The way we determine [protein intake] is by a concept called the nitrogen balance”

How much you actually need depends on your weight, sex, and activity level. Per day, the average person adult needs about 0.66 grams of protein (pdf) per kilogram that they weigh, according to the US Department of Agriculture’s Food and Nutrition Board. For the average American man who weighs about 196 pounds (about 89 kg), that’d be 59 grams of protein; for the average woman who weighs about 166 pounds, about 50 grams.

There’s some disagreement in the field. The Food and Drug Administration’s (FDA) recommendations are slightly different: 0.8 grams per kilogram per day. Others say these are low numbers that represent just the basic amount of protein that you need to function on a basic metabolic level—sitting on the couch, just existing. A further review (paywall) of the literature suggests that if you are at least moderately active, the right amount is actually around 1.2 grams per kilogram. The most athletic among us recreational athletes would need about 1.7 grams per kilogram—a maximum of 151 and 128 grams for the average man and woman, respectively.

Most Americans, though, probably aren’t active enough to need those higher amounts, but they’re eating it anyway: At the FDA’s recommendation, the average man should be getting about 71 grams of protein, and the average woman should get about 60. In 2012, though, most American men over 20 ate about 99 grams of protein per day, whereas women over 20 ate about 68 grams, according survey results (pdf) published by the US Department of Agriculture.

Perhaps it’s because protein can help you stay fuller for longer. “There’s a natural inhibitory effect of high amino acids, and the rate at which the stomach releases the content into the small intestine,” says David Levitsky, a psychologist at Cornell who specializes in our relationship with food. You can imagine the advantages for someone trying to lose weight—it’s one of the reasons Paleo is so popular.

In addition, the perception is that protein is linked to athleticism. Protein helps with muscle synthesis, and as such is an important part of the recovery process for elite athletes shortly after a tough workout. “It’s like putting a dry sponge in water” says Amy Goodson, a sports nutritionist at the Texas Health Physicians Group in Fort Worth, Texas—muscles soak up and utilize protein and carbohydrates rapidly after exercising. And, she adds, after you eat protein, “the body recognizes the need for recovery, and really goes into the recovery process.”

The perception is that protein is linked to athleticism.

It’s one of the reasons that the American College of Sports Medicine’s recommends that those who are physically exerting themselves regularly get 2 grams (paywall) of protein per kilogram they weigh every day. But most of us are not serious athletes. And even if you’re a recreational athlete—if you, say, hit the gym three or four days a week and spend a little time walking during the day— “I don’t think it’s necessary,” says Travis Thomas, a sports nutritionist at the University of Kentucky and co-author of the recommendations. The average person doesn’t need to eat a high-calorie protein shake after just 30 minutes on the treadmill, says Goodson. It may even be detrimental if you’re trying to lose weight—you could end up eating more calories than you just burned off.

“Edible foodlike substances”

It makes sense that we’ve become enamored with protein. It’s sold as a simple, easy way to be healthy and nutritious—who wouldn’t want to think their workout habits necessitate them to refuel like Usain Bolt, with just a fraction of the actual commitment?

“We [want to] maximize the number of calories we consume and minimize the amount of work to get them,” Levitsky says. “You want more protein, you want to build muscle. It’s a natural thing to do.”

Who wouldn’t want to think their workout habits necessitate them to refuel like Usain Bolt, with just a fraction of the actual commitment?

But it’s obviously not a silver bullet. “Protein in and of itself isn’t going to make you into a supermodel, get you to your ideal weight or make you into a lean, mean machine,” Andrea N. Giancoli, a dietician and policy analyst for the Beach Cities Health District in California, told the Washington Post. “You actually have to exercise and do the work to build that muscle.”

The other thing is that when we distill protein—or any technically good nutrient—we lose out on so much more. As science writer Michael Pollan pointed out in his book “In Defense of Food,” often when we think about nutrition, we forget that we’re actually talking about food. What we eat has become so processed to concentrate things like protein and minimize things like fat, that in many cases we’re left with “edible foodlike substances”—not food.

We never needed powders made from distilled protein in the past, and we can still get all the protein need through a balance of plant and animal products. Most nutritionists agree that a plant-based diet—either eating only plant products, or eating meat sparingly—can cover you, without any of the negative side effects of a meat-heavy lifestyle (lots of fat, lots of calories, and increased risk of all sorts of negative health effects, including heart disease and cancer). If you’re so inclined, you can even get it all from plants—vegans can get by just fine.

So will the protein-packed nutrition bars make you sick, or cause you to gain weight? Probably not. But it’s almost certainly healthier to seek out your protein in a more natural form. “If you’re concerned about your health, you should probably avoid products that make health claims,” Pollan writes. “Why? Because a health claim on a food product is a strong indication it’s not really food, and food is what you want to eat.”