Americas Protein Obsession May Be Doing More Harm Than Good, Experts Warn

The protein craze has officially outgrown gym culture. What once belonged to bodybuilders and athletes has become a full-blown lifestyle trend, with protein now pumped into everything from waffles and coffee to ice cream and cereal. But as influencers urge even non-athletes to chase ever higher daily protein targets, nutrition experts warn the movement has veered far beyond what science supports — and may be quietly harming the very people embracing it most.

At the heart of the debate is the gulf between online advice and established guidelines. Social media influencers regularly promote consuming 1 gram (or more) of protein per pound of bodyweight — roughly 2.2 grams per kilogram — despite the Recommended Dietary Allowance being just 0.8 grams per kilogram for healthy adults. That disconnect, experts say, has fueled a surge in ultra-processed, protein-fortified foods now marketed to non-athletes like suburban moms and office workers, particularly women.

Award-winning gastroenterologist and bestselling author Dr. Will Bulsiewicz, founder of 38TERA, says protein is important, “but the hype has gone way beyond the science and may actually be causing more harm than good.”

“The truth is that we don’t really have a protein problem,” Bulsiewicz says. “We have an exercise problem — just 24% of Americans meet the recommended amounts of aerobic and resistance exercise. And we have an even bigger fiber problem, with 95% of us being fiber deficient. So in prioritizing protein, were trying to solve a problem we dont actually have, and in the process distracting ourselves from the solutions that actually would transform our health.”

Bulsiewicz said there is “not a single evidence-based guideline” supporting the influencer-promoted numbers for non-athletes, and the push to hit those targets can lead to gut issues.

“There isnt a single evidence-based guideline that recommends that level for non-athletes,” he said. “To get there, people end up overconsuming animal products or relying on protein supplements, which often causes gut issues like bloating, gas, and constipation. Honestly, Ive never met a protein powder that didnt cause bloating.”

Women, he said, are among the most vulnerable.

“Many women struggle with bloating, constipation, and gut symptoms — all of which can get worse with high-protein, low-fiber diets,” he said. “The irony is that the same women being sold these protein-heavy trends are also the group most negatively affected by a depleted gut microbiome.”

He called 1.2–1.6 grams per kilogram the “evidence-based sweet spot,” depending on activity level.

“High-protein, low-fiber diets increase inflammatory compounds like TMAO, ammonia, and hydrogen sulfide. They also promote microbes such as Bilophila wadsworthia, which are associated with gut inflammation,” he says. “In my new book, Plant Powered Plus (Avery, Jan. 13, 2026), I talk about how these compounds can increase intestinal permeability and low-grade inflammation that extends beyond the gut.”

Dr. Brian J. Cole, sports medicine orthopedic surgeon and managing partner of Midwest Orthopaedics at Rush, says “most healthy women already meet their daily protein needs through normal eating.”

“For non-athletes, the focus should be balanced meals and consistent physical activity rather than maximizing protein at every opportunity,” says Cole, who is also a team physician for the Chicago Bulls and White Sox.

“Protein itself isnt harmful, but the way people are increasing it can be,” he says, pointing out that many products with added protein are ultra-processed and high in calories and sugar.

“Overemphasizing protein can also push out fiber-rich foods — something many women are already not getting enough of — which can lead to digestive issues and lower energy,” Cole says. “Excess protein may strain the kidneys in people with underlying disease, and emerging research suggests very high protein diets could be linked to increased cardiovascular risk.”

Sports medicine physician Dr. Jeremy Alland, also of Midwest Orthopaedics at Rush and a team physician for the Bulls and White Sox, said the “craze” began when consumers realized the RDA is designed to prevent deficiency rather than optimizing performance. But he noted that even athletes seldom need more than roughly 1.6–1.7 grams per kilogram.

“As a sports medicine physician and someone who cares about aging the best I can, I totally get why everyone is suddenly reaching for protein everything,” Alland says. “I think 0.5 g of protein per pound of body weight makes sense for most people.”

He warns that adding protein to packaged foods often masks what they really are.

“This is classic health-halo marketing. Add 10 grams of protein to a coffee or cereal, and suddenly it feels like a healthy choice even if its still full of added sugars, refined starches, or saturated fats,” Alland says. “Theres a lot of important conversation happening right now about ultra-processed foods and their effects on metabolism, appetite, and long-term health. Many protein bars, shakes, and fortified snacks fall squarely into that category.”

While most healthy adults “wont get significant medical problems” from high protein loads, Alland says prolonged consumption above 2 grams per kilogram per day has shown risks ranging from digestive problems to kidney strain. He also highlighted research connecting high animal-protein diets to type 2 diabetes, fatty liver disease, and cardiovascular concerns. Plant-based whole-food proteins, he noted, are associated with lower mortality.

Dr. Michael Ednie RD/MD, Chief Medical Officer at Bespoke Concierge MD, drew a sharp distinction between whole-food protein and highly processed protein-enriched products, and said that for most healthy, non-athlete adults, the RDA of 0.8g/kg/day is generally sufficient.

“Whole-food protein sources are minimally processed foods such as meat, fish, eggs, dairy, legumes, nuts, and seeds, while highly processed protein products (e.g., protein bars, shakes, plant-based meat analogues) are industrially manufactured and often contain additives, preservatives, and altered nutrient profiles,” Ednie says, noting that whole food protein sources also provide essential amino acids, fiber, vitamins, minerals and bioactive compounds that support overall health.

“The American College of Sports Medicine recommends 1.2–2.0 g/kg/day for athletes, with the higher end of the range appropriate during periods of intense training, energy restriction, or recovery from injury. The International Society of Sports Nutrition similarly recommends 1.4–2.0 g/kg/day for exercising individuals, with even higher intakes (up to 2.3–3.1 g/kg/day) during hypocaloric periods to preserve lean mass. Endurance athletes may require up to 1.8 g/kg/day or more, especially during carbohydrate-restricted training,” Ednie says.

But even for active individuals and athletes, he says sustained overconsumption of protein “should be avoided.”

“For active individuals and athletes, higher protein intakes (up to 2g/kg/day) are generally considered safe and may be beneficial for muscle adaptation and recovery. However, prolonged intake above 2g/kg/day should be avoided due to potential adverse effects, including renal stress, increased glomerular filtration, and possible bone mineral loss, especially if intake is sustained over years,” he says.

Alland also connects the fixation on protein to rising rates of disordered eating.

“Eating disorders are at an all-time high, and part of what concerns me is how food is increasingly being treated as a collection of macros instead of something that fuels us and brings us together,” he says. “When we reduce everything to protein counts and grams, we risk driving even more disordered eating. I always bring my patients back to the basics: eat real food, mostly plants, have regular meals, avoid ultra-processed foods, and sit down to eat with people you love. Those habits offer far more long-term health benefits than obsessing over any single macronutrient. If youve nailed those fundamentals, then paying some attention to protein is totally reasonable.”