Popular High-Protein Diets Could Make You Gain Weight

The high-protein diet trend may not be healthy in the long-term, according to new research findings. (Photo: Stocksy/Davide Illini)

High-protein diets are having a moment in nutrition — and with celebrities. Jessica Biel swears by Paleo, Kate Middleton reportedly is a Dukan Diet devotee, and Kim Kardashian has said she “loves” Atkins. But a new large study out of Spain is calling the long-term effectiveness of these diets into question.

According to research published in the journal Clinical Nutrition, eating a high-protein, low-carb diet can actually cause weight gain in the long-term.

For the study, researchers from Spain’s Rovira I Virgili University analyzed data from more than 7,000 men and women. The subjects filled out questionnaires about their food habits between 2003 and 2009. The experts discovered that people who ate high-protein diets had a 90 percent greater risk of gaining more than 10 percent of their body weight over time.

But weight gain wasn’t the only issue: People who had higher protein intakes also had a 50 percent greater risk of death during the study period when they replaced carbs in their diet with protein — and a 66 percent increased risk of death when they replaced fat in their diet with protein.

The American Heart Association also warns about the potential negative health consequences of these diets and specifically says on its website that it “doesn’t recommend high-protein diets for weight loss.”

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So why are these diets still so popular? It’s because they work — in the short-term at least, says certified dietitian-nutritionist Lisa Moskovitz, RD, CEO of NY Nutrition Group.

“When on a high-protein diet, most people feel more satisfied and fuller for longer periods of time as protein takes longer to break down in the stomach and burns more calories during the digestion process,” she tells Yahoo Health. “They also tend to eat less carbohydrates such as bread, pasta, chips, baked goods, etc., which tend to cause more cravings and increased appetite.”

However, eating too much protein can also cause weight gain, she says: “Any protein that is not used in the body for recovery and repair is either filtered out by the kidneys, or even more likely, converted in to fat for later energy use.” (To be fair, any calories not used by the body can be converted into fat.) Weight gain — no matter the cause of it — is linked to an increased risk of developing type 2 diabetes, heart disease, and stroke.

But the biggest drawback to following a diet that’s high in anything is that it’s also potentially low in something important, says registered dietitian-nutritionist Jill Weisenberger, author of The Overworked Person’s Guide to Better Nutrition.

“Often when people follow high protein diets…they might also be consuming an inadequate amount of health-boosting foods such as fruits, legumes, and whole grains,” Weisenberger tells Yahoo Health. “As important as what we do eat is what we do not eat. And we know that there are thousands of disease-fighting phytochemicals in fruits, vegetables, whole grains, legumes and nuts.”

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But while a high-protein diet can be dangerous for your long-term health, lean protein still has an important part in any balanced diet. For optimal health and weight loss, Moskovitz recommends that people strive to eat a diet balanced in high-fiber carbohydrates, lean protein, and healthy fats, specifically aiming for a diet that’s 45 to 55 percent carbs, 25 to 30 percent fat, and no more than 20 to 25 percent protein.

Weisenberger also recommends spreading that protein intake out over the course of the day instead of just having, say, a large steak at dinner. And, as she points out, calories matter: “For a high protein diet, or any diet, to cause weight loss, there must be an overall reduction in calories.”

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