The Effects Of A High Protein Diet On Indices Of Health And Body Composition – A Crossover Trial In Resistance Trained Men

This study examined whether consuming very high amounts of protein could be harmful to health, particularly liver and kidney function, in men who regularly lift weights. Researchers followed 12 healthy, resistance-trained men (average age 26) through a 16-week crossover study where each participant spent 8 weeks eating their normal diet and 8 weeks eating a high-protein diet containing more than 3 grams of protein per kilogram of body weight daily.

During the study, participants consumed an average of 2.6 grams of protein per kilogram during their normal diet phase and 3.3 grams per kilogram during the high-protein phase. For a 180-pound man, this would translate to about 270 grams of protein per day during the high-protein phase - significantly more than typical recommendations. The researchers tracked various health markers including blood lipids, kidney function tests, liver enzymes, and body composition changes throughout both phases.

The key finding was that consuming these very high amounts of protein for 8 weeks did not cause any harmful effects on clinical health markers, including kidney or liver function. This challenges common concerns that high protein intake might strain these organs in healthy individuals. The study also looked at body composition and performance changes, providing insight into whether such high protein intake offers benefits beyond just being safe.

This research is particularly relevant for patients interested in optimizing their nutrition for muscle building, weight management, or metabolic health. In clinical practice, this data can help inform discussions about protein intake recommendations, especially for active individuals who may benefit from higher protein consumption without worrying about organ damage, assuming they have healthy kidney and liver function to begin with.