Updated July 21, 2025 at 1:26 PM CDT
Emiliano Slesaransky, 17, joined Santa Monica High School's football team as a freshman and — at the urging of coaches and teammates— started hitting the gym whenever possible: in the morning, after school and on the weekends. The people he met there would share their strategies for bulking up.
"They would take protein powders, other supplements like some people I know take ashwagandha, and maybe creatine," he says, citing popular energy and exercise-enhancing supplements. Emiliano started taking some of them, too.
But his dad, Eduardo Slesaransky, wanted to make sure his son's diet — and attitude — remained balanced: "My concern was the influence that social media has on these supplements and these kinds of things and the culture of bodybuilding and the gyms."
Protein supplements are big on social media, where influencers are helping drive sales of protein bars, shakes and powders. A poll of parents by the Mott Children's Hospital at the University of Michigan last fall found 40% of teens consumed some type of protein supplement in the past year.
"Teen boys were more likely — twice as likely — to consume protein every day," says Sarah Clark, a research scientist and co-director of the poll.
Girls, she says, more often relied on supplements as meal replacements, and the inspiration to consume protein shakes, bars or powders often came from coaches, peers, or influencers on social media. But Clark says parents were also among those promoting protein to their children.
"I wonder if, as parents, we are recognizing how much messaging we have taken in about protein being good," she says. "We have absorbed this messaging: That's the key to being healthy," she says, when in fact it is only one factor in a balanced, healthy diet.
How much is enough?
There is also such a thing as too much protein, says Abriana Cain, a pediatric dietitian with Children's National Hospital in Washington, D.C. As a general rule, Cain tells teens and parents to gauge protein intake based on size — benchmarked at roughly 1 gram of protein a day per kilogram of body weight. (For a 150-pound teen, that amounts to about 68 grams of protein per day — or the rough equivalent of a cup of cooked chicken, a cup of yogurt and a cup of black beans.)
"It might even increase from there, based on their physical activity needs," she says.
Cain says more than 100 grams a day can damage the kidneys and liver in the longer term. It can also cause stomach pain, as it did for one of her patients. "They were eating protein supplements with all of their meals and also with all of their snacks, and they were having a lot of abdominal pain."
The vast majority of teens, Cain says, already get enough protein in their diet without supplements.
There are also concerns about the marketing of supplements.
There is no quality control for these products, notes pediatrician and eating disorder expert Dr. Jason Nagata, at the University of California San Francisco. Supplements, including protein bars and powders, are not regulated by the Food and Drug Administration in the same way as drugs — so they're not tested before going on the market, and their ingredients aren't verified before they are sold. Manufacturers are responsible for evaluating the safety and labelling of their products. The FDA does have the authority to take action against any adulterated or misbranded dietary supplement product after it reaches the market.
"I think it's important for teens and parents to know that there isn't that kind of rigorous quality control, especially when you're getting mixtures of muscle-building supplements and products," he says. "I would just be very cautious."
Nagata advises researching, reading ingredient labels and buying directly from known companies. Some products have been found to have contaminants such as heavy metals, bacteria, or chemicals or adulterants not listed on the label.
Eating disorders are up
Separately, Nagata is concerned that the protein craze is contributing to the alarming increase in eating disorders among boys over the past two decades worldwide. He observes that over that time period, action figures like Batman and Superman are sold with bigger muscles, and pressures on ordinary teenagers to post attractive photos of themselves to be popular online have increased.
"The masculine body ideal has become increasingly large and muscular, and so more and more boys are trying to become muscular now than they have ever before," he says.
Emiliano Slesaransky stopped using protein powders about a year ago, he says, largely because he started forgetting to take it.
His father, Eduardo, says his son still looks very strong and fit, but is no longer fixated with bulking up for sports. "He's focusing on getting into college."
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