Fueled by the rise of social media and a lucrative, unregulated supplements industry, more boys and young men today are bulking up to the point of risking their overall health. A measured amount of weight training can be positive and healthy, but it’s neither when body image turns into an obsession or exercise becomes excessive.

Nagata published research in the Journal of Adolescent Health in 2019 that found about a third of teenage boys reported trying to gain weight. The study was based on data from more than 15,000 high school students in the 2015 Youth Risk Behavior Survey. And in Current Opinion in Pediatrics in 2021, Nagata and his co-authors wrote that about 22 percent of teen boys and young men are engaging in some sort of muscle-building behavior.

The red flag for a young man or a teenage boy is when exercise or food choices lead to preoccupations or obsessions with appearance, body size, weight or exercise in a way that worsens their quality of life, Nagata says.

“It’s not just the activity itself, it’s also the way the activity makes them feel,” Nagata stresses. “So when someone says that the exercise is really causing them more worry or preoccupation than joy, and when it starts to impair their schoolwork or social functioning, those are all red flags regardless of the actual activity, but just how they perceive it.” More warning signs on body image

Gabriela Vargas, a pediatrician and director of the Young Men’s Health website at Boston Children’s Hospital, urges parents to look for boys becoming hyper-fixated on what they’re eating, having highly regimented meals, cutting out specific types of food groups (such as carbs or sugars) or dramatically increasing the amount of protein that they’re taking in. Going from one protein shake a day to five or having a pre- and post-workout shake multiple times a day is a nutritional warning sign.

“If a parent sees their teen engaging in hyper-exercising or protein supplement use, I would encourage them to have a conversation with their teen as to why they are changing their behavior,” Vargas says. “They should share their concerns with the teen and encourage the teen to reduce their exercise and/or protein supplement use.”

She also encourages parents to speak with their child’s primary care doctor if they’re worried about behavior.

Bulking up, with the associated risky behaviors of skewed nutrient intake and excessive exercise, can be as dangerous as the drastic weight loss associated with more frequently discussed eating disorders such as anorexia. When a growing teen has energy deficits from either not enough caloric intake or too much exercise, they’re not getting adequate nutrition to match the energy they’re exerting either through exercise or their baseline metabolic needs.

“Boys with eating disorders, if they’re in this relative malnutrition state, they will have lower testosterone levels and lower libido levels,” he says. “I think one of the big challenges is many of these boys and young men are engaging in these behaviors with the ultimate goal of increasing or maximizing their performance and appearance. But in the end, it can actually stunt their growth.”

In younger boys still in the early stages of puberty, a relatively low level of testosterone can also lead to limited gains in muscle mass.

“Boys feel a lot of pressure when they’re in that stage of development where they haven’t really gone through the later stages of puberty yet,” says S. Bryn Austin, a professor in Harvard University’s Department of Social and Behavioral Sciences. But they “don’t have the same kind of hormonal environment” to support significant muscle gain, which means there isn’t a lot of potential to gain muscle mass for the average 10- to 14-year-old boy who lifts weights and drinks protein shakes

Although muscle strength can improve performance in sports, often this pursuit of the ideal male body isn’t to do better on the field, but to look better — or more muscular — in the mirror. The goal isn’t bigger, stronger and faster. It’s just bigger.

“In terms of how boys and young men learn about masculinity, just being big is a way of expressing masculinity and dominance,” Austin says.

Studies looking at boys’ action figures have found that, over a 25-year period, the toys have become more muscular, with bulging biceps and broad chests. “The increase in action figure dimensions may contribute to the multifactoral development of an idealized body type that focuses on a lean, muscular physique. This occurrence may particularly influence the perceptions of preadolescent males,” the researchers wrote.

Related research has shown that boys prefer those hyper-muscularized toys over their skinnier predecessors.

“They’re exposed to [examples of muscularity] at a very early age,” Nagata says.

“So, late childhood, late elementary school, early adolescence, boys are learning, they’re learning about what the expectations are about this, the so-called ideal body that they are expected to grow into,” Austin notes.

And what starts with toys and cartoon superheroes is amplified through social media platforms such as TikTok and Instagram. With algorithms directed at funneling content, all it takes is a click, or even a pause on muscle-building content and users will keep getting more and more. This can foster an illusion that everyone is muscular or engaging in muscle-building behavior.

“Because it’s also such a societal norm,” Vargas says, “it’s really tough for parents to figure out when is this just my kid as a teenager versus my kid has a problem.”

“I think the added pressure with social media is that with all those traditional forms — books, television, movies — back in the day, most people were living in a read-only environment,” Nagata says. “For the most part, your average teenage boy would not expect to be featured in a movie or become a celebrity.”

Research looking at social media effects on teenage boys found that disordered eating behavior, muscle dissatisfaction and use of steroids are associated with more time spent on Instagram. “Findings like these demonstrate that social media can create pressures for boys to display and compare their muscular physiques,” Nagata says.

If social media is the fire, supplements are the gasoline. The use of muscle-building supplements is pervasive, with more than half of boys and men in adolescence through early adulthood taking protein powder or shakes.

The products, which are marketed heavily to boys and men, are not federally regulated for safety or effectiveness and leave unanswered questions of safety. “There’s a lot of research done where they do lab tests on these products and what they say on the label is not even reflective of what’s actually in these bottles, pills, powders,” Austin says.

Trying to figure out what’s safe for an adolescent to use is virtually impossible, experts say. Because of these unknowns, Vargas advises adolescents not to take any supplements.

“If they then want more guidance, then I will refer them to a dietitian within our clinic or a dietitian in the community,” she adds.

... the American Academy of Pediatrics recommends 60 minutes of daily physical activity for children and teens, and exercise and strength training can be a positive for many. But “if a young person wants to increase their physical activity I encourage them to talk about this with their parents, coaches and primary care provider,” Vargas says.