Protein has long been praised for its role in building muscle, supporting metabolism and keeping us full for longer. As a result, high-protein diets have surged in popularity, with many people actively looking for ways to increase their daily intake. But can you have too much of a good thing?
A June 2 report by Sophie Egan in The New York Times highlights that while protein is an essential nutrient, consuming more than the body needs may carry certain health risks. The report outlined five potential concerns linked to excessive protein intake. A 2025 survey of 3,000 US adults found that 71% were trying to eat more protein, up from 59% in 2022. (Also read: Bengaluru fitness coach shares simple ‘high-protein diet hack’ to lose weight sustainably: ‘Moong sprouts contain 25 g…’ )
While protein is an essential nutrient, experts say that more is not always better. Bettina Mittendorfer, professor of nutrition and exercise physiology at the University of Missouri School of Medicine, told The New York Times that consuming significantly more protein than recommended may come with certain health risks. She noted that potential concerns can arise when people regularly consume well above 1.2 grams of protein per kilogram of body weight per day.
Here are five risks experts highlighted:
1. Increased risk of heart disease and Type 2 diabetes
Much of the protein consumed in the United States comes from animal-based foods. According to a 2021 study by researchers from the US Department of Agriculture, animal foods such as beef, chicken and cured meats account for nearly 70% of people’s protein intake.
Donald Hensrud, associate professor of nutrition and preventive medicine at the Mayo Clinic College of Medicine, told The New York Times that diets high in red and processed meat have been linked to a greater risk of heart disease and Type 2 diabetes.
Research published in 2023 found that eating an additional 100 grams of red meat daily was linked to an 11% higher risk of heart disease, while an extra 50 grams of processed red meat per day was associated with a 26% higher risk. Another large study found that people with the highest red meat intake had a significantly greater risk of developing Type 2 diabetes.
According to Dr Hensrud, saturated fats in red and processed meats can increase LDL, or “bad” cholesterol, while also contributing to inflammation and insulin resistance.
2. Greater risk of certain cancers
High consumption of red and processed meats has also been linked to certain cancers, particularly colorectal cancer. A 2024 study reported that diets rich in red meat were associated with a 30% higher risk of colorectal cancer, while processed meat consumption was linked to a 40% increase in risk.
Dariush Mozaffarian, cardiologist and director of the Food Is Medicine Institute at Tufts University, recommends prioritising healthier protein sources such as beans, lentils, soy foods, nuts, fish and yoghurt.
3. Constipation and digestive issues
Marc O’Meara, a nutritionist at Brigham and Women’s Hospital in Boston, told The New York Times that people trying to increase protein intake often reduce their consumption of fibre-rich foods such as vegetables and whole grains, especially when following low-carbohydrate diets.
Fibre plays a key role in maintaining healthy digestion, supporting the gut microbiome and promoting regular bowel movements. Inadequate fibre intake may contribute to constipation, bloating and other digestive complaints. O’Meara recommended aiming for balanced meals that include vegetables, whole grains and protein rather than focusing heavily on protein alone.
4. Weight gain
Although protein can support weight management, eating more than the body requires can still contribute to weight gain. According to Dr Mozaffarian, excess calories from protein are ultimately stored as fat if they are not used for energy. Larger portions of protein-rich foods can also significantly increase calorie intake compared to vegetables and other nutrient-dense foods.
5. Kidney-related concerns
For people with healthy kidneys, high protein intake is unlikely to cause significant problems, according to Dr Hensrud. However, the situation may be different for individuals with chronic kidney disease.
He explained that processing large amounts of protein can place additional strain on kidneys that are already functioning below normal capacity. Excessive animal protein intake may also increase the risk of kidney stones, although staying adequately hydrated can help lower that risk.
The bottom line
Protein remains a vital nutrient, but experts say there is little evidence that consuming excessive amounts offers additional health benefits for most people. Instead, nutrition specialists recommend focusing on a balanced diet that includes a variety of protein sources, particularly plant-based options, alongside fruits, vegetables and whole grains.
Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.
