Health specialists are cautioning that an overly high-protein diet may raise the risk of a “silent killer” that affects more than one in seven U.S. adults, many of whom do not know they have it.
Protein-heavy eating plans have become increasingly popular online, with many fitness influencers promoting them as a way to lose weight and gain muscle. But experts say the social media trend can carry health risks when taken to extremes, especially when it crowds out other parts of a balanced diet.
Although protein is an essential part of a well-rounded diet, doctors say consuming excessive amounts on a regular basis may place unnecessary strain on the body in people who already have kidney disease or are at higher risk of developing it.
Medical professionals warn that, while most people with healthy kidneys can tolerate higher protein intake without major issues, a significant minority could unknowingly be putting themselves at risk of kidney disease or worsening undiagnosed kidney problems.
Dr Carl May, a kidney expert at University of Bristol, told the Mail Online:
“Protein puts a lot of stress on the kidneys because the organ struggles to process it. So consistently eating above the recommended amount is going to be tough on them.
“For around nine out of ten people, this won’t lead to anything serious. But that unlucky 10 per cent could be quietly damaging their kidneys without realising it.
“This means those patients may be creeping towards kidney failure. If that happens, you’re probably looking at an organ transplant.”
Experts say the biggest concern is not protein alone, but very high-protein diets that are sustained over time in people with diabetes, high blood pressure, existing kidney disease, or a family history of kidney problems. Chronic kidney disease is often called a silent condition because it can develop gradually and cause few noticeable symptoms until it is advanced.
Experts have also pointed to the possibility of kidney stones developing in people who follow extreme protein-focused diets, particularly when those diets are heavy in animal protein and low in fluids, fruits, vegetables and other fiber-rich foods.
ABC News chief medical correspondent Dr. Tara Narula explained:
“If you eat a diet that is a carnivore diet – very high in beef, chicken, poultry or seafood – you’re going to potentially break that down into uric acid, which, under the right conditions, can crystallize and form stones,” Narula added.
“We’re talking about levels that are really two to three times the recommended level of protein, where you’re not really drinking water, you’re not eating fruits or vegetables and getting other carbohydrates. About 200 grams of protein or more.
“What you can do is swap in some plant protein – legumes, beans, nuts, tofu, soy – so you’re not just fully focused on animal protein.”
Guidance from health authorities says protein should generally make up about 10 to 35 percent of daily calorie intake for healthy adults, while the standard recommended dietary allowance is 0.8 grams per kilogram of body weight per day to prevent deficiency. People who exercise intensely, older adults and those trying to lose weight may need more protein than the minimum, but needs vary by age, activity level and health status.
For people with chronic kidney disease, doctors often recommend adjusting protein intake based on the stage of illness and overall nutrition goals. In some cases, reducing protein can help ease the workload on the kidneys and slow progression of disease, but dietary changes should be individualized and made with medical guidance.
Even so, some reports suggest certain people are consuming far more than they need in pursuit of better health, a habit experts say may come with serious consequences if it is extreme, unbalanced or used by people with undiagnosed kidney problems.