Is too much protein dangerous? High-protein diets may increase heart failure risk by nearly 50 percent, study suggests

Credit: Sean Gallup, Getty Images

Credit: Sean Gallup, Getty Images

Researchers are warning against some high-protein diets, such as the trendy Atkins diet that are often used for weight loss but may inadvertently lead consumers to eat large amounts of protein.

According to a new study from Finland, which examined nearly 2,500 middle-aged men between the ages of 42 and 60 for about 22 years, such diets may increase risk of heart failure, a condition in which the heart is unable to pump enough blood for proper body functioning.

During the study, which was published Tuesday in the journal Circulation: Heart Failure, researchers found 334 diagnosed cases of heart failure, 70 percent of which involved patients that consumed protein from animal sources and 27.7 percent from plant sources.

A higher protein intake from most dietary sources was associated with a slightly higher risk of heart failure. Fish and eggs were the only proteins not associated with increased risk of heart failure.

By comparing the men who ate the most protein to those who consumed the least, the researchers assessed risk of heart failure by protein source.

Here’s what they found:

  • 33 percent higher risk for all protein sources
  • 43 percent higher risk for animal protein
  • 49 percent higher risk for dairy protein
  • 17 percent higher for plant protein

"As many people seem to take the health benefits of high protein diets for granted, it is important to make clear the possible risks and benefits of these diets," study author Dr. Jyrki Virtanen, of the University of Eastern Finland, said in a statement. "Earlier studies had linked diets high in protein especially from animal sources with increased risks of Type 2 diabetes and even death."

But Virtanen and the rest of the team believes more research needs to be conducted to confirm the findings, which only found an association between a high-protein diet and heart failure, but did not conclude that a change in protein consumption would prevent heart failure.

While the ketogenic and Atkins diets aren't marketed as high-protein diets, those following the diets often end up eating high amounts of protein, according to Live Science.

In fact, one of the biggest mistakes people run into when trying the keto diet is consuming too much protein. But keto is actually meant to be a high-fat, moderate-protein and low-carb diet.

Atkins dieters deal with similar issues during the carb-restricting weight-loss plan.

"Patients come to me all the time asking if more protein will help them in weight loss," Kathy McManus, of the Harvard University-affiliated Brigham and Women's Hospital, said in a Harvard blog post. "I tell them the verdict is still out. Some studies support it, some studies don't."

How much protein should you consume?

There is no strict consensus in the medical community regarding how much protein is optimal for good health, though research is ongoing.

The recommended dietary allowance for protein - the number of nutrients needed to meet your basic nutritional requirements - is about 0.8 grams of protein per kilogram of body weight. Use this online protein calculator to determine your RDA for protein.

But researchers, along with the American Heart Association, recommend a diverse, well-balanced diet of fruits, vegetables, whole grains, low-fat dairy products, poultry, fish, beans, non-tropical vegetable oils and nuts for good health. The AHA also urges the public to limit consumption of sweets, red meats and sugar-sweetened beverages.

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