Study reveals excessive amounts of protein could make you gain pounds

We all know that protein is an essential factor in postride recovery: It provides the amino acids you need to help build muscle. But piling up on the protein after your ride might not be helping you and could actually be making you pack on some extra pounds over time.

Or at least that’s what the findings of a recent study published in the journal Clinical Nutrition seem to suggest. When researchers tracked the weight and dietary patterns of more than 7,000 adults from 2003 to 2009, those whose diets were made up of more than 20 percent protein (especially animal protein) were significantly more likely to gain more than 10 percent of their body weight compared to people whose diets contained less than 15 percent protein. Even scarier: High-protein eaters also had a 50 percent higher risk of dying during the study period than low-protein eaters.

It’s true that protein can help you stay satisfied longer and help you build muscle that will boost your body’s calorie-burning potential. Even so, eating too much of any kind of food—including protein—will eventually lead to weight gain. Plus, going too heavy on the stuff can have more serious health consequences. Too much protein might mess with your body’s ability to metabolize glucose, and can also cause problems with kidney function, says study coauthor Mònica Bulló, PhD.

Clearly, these are legitimate concerns. Still, the study neglected to answer some big questions that could have had a major impact on its outcome. First, the researchers didn’t look at body composition. And since the findings showed that high-protein eaters gained weight but didn’t increase their waist circumference, there’s no way to know for sure whether they were packing on fat or muscle mass.

What’s more, the researchers didn’t ask about the kind of animal protein study participants were consuming. “Was the protein lean or fatty? Grass-fed or grain-fed? Those factors can lead to different outcomes for your health,” says Cynthia Sass, RD, author of Slim Down Now. In other words, you’re way more likely to get fat or sick from eating fast-food burgers and fish sticks than organic, grass-fed beef and wild-caught salmon.

All of this adds up to findings that sound frightening at first, but appear to lack some of the major details that you’d really need in order to determine whether eating a high-protein diet, like Paleo, is actually bad for you.

The bottom line: If you’re making lean, quality protein a mainstay of your diet, you’re probably in good shape. Just don’t go crazy. “It always comes back to balance. I find that even with really active people, nobody needs more than about 30 percent of their calories from protein,” Sass says. (If you’re eating 1,800 calories a day, that’s about 135 g.) “When you look at that percentage, even if it’s all coming from animals, that still means the other 70 percent can come from plant-based foods.”