High-protein diets such as the keto diet and the Atkins diet are very popular nowadays, but these diets may increase the chance of heart failure in middle-age men, a new study from Finland suggests.

The researchers examined information from over 2,400 men ages 42 to 60, who kept track of the meals they ate for four days. (The men in the study weren’t advised to adhere to any specific diet) Afterward, the men were split into four groups based on how much protein they ate, with the lowest group consuming roughly 78 grams daily, on average, and the highest group consuming 109 g every day. The participants were then tracked for 22 years, during which about 330 were diagnosed with heart failure.

(Technically, the keto diet and the Atkins diet are not high-protein diets; the keto diet is a high-fat, moderate-protein diet, and the Atkins diet is a low-carb diet. People following the diets, nevertheless, often end up eating high amounts of protein)

The researchers found that the men in the group that ate the most protein were 33 percent more likely to be diagnosed with heart failure during the follow-up period, compared with people from the group who ate the least protein.

The findings were accurate for most sources of protein: People who ate the most animal protein were 43 percent more likely to be diagnosed with heart failure; and individuals who ate the most dairy protein were 49 percent more likely to be diagnosed with heart failure, compared to people who ate the least amounts of animal and diary protein.

Plant protein seemed less risky: Eating high levels of plant protein has been linked with a 17 percent increase in the chance of heart failure, compared with eating low amounts.

The research, which was published May 29 in the journal Circulation: Heart Failure, is among the very first to look at the connection between high-protein diets and heart failure, a condition where the heart muscle can not pump sufficient blood to meet the body’s ordinary demands.

“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 senior author Jyrki Virtanen, an adjunct professor of nutritional epidemiology at the University of Eastern Finland, said in a statement.

However, the researchers stressed that more studies are necessary in diverse populations to validate the findings. The analysis also only found an association between a high-protein diet and heart failure, and can’t ascertain whether altering the amount of protein in a person’s diet would prevent heart failure.

High protein and heart health

The new study alone is not sufficient to advocate against low-carb diets for men, stated Dr. Andrew Freeman, director of the Cardiovascular Prevention and Wellness program at National Jewish Health hospital in Denver, that wasn’t involved with the new study. However, the findings contribute to a growing body of literature suggesting that high-protein diets might be detrimental to heart health, he said. For instance, diets high in saturated fat, which is found mainly in dairy and meat products, are connected with a greater chance of heart attack and stroke.

“The overall sum of the data that’s out there would suggest that the high-protein diet that’s become a fad as of late is not necessarily the most ideal diet,” Freeman advises. In general,“Americans consume way too much protein,” and might wish to think about avoiding excessive amount of protein in their daily diet, he added.

The U.S. government urges that people consume about 0.8 g of protein per kilogram of body weight, or 0.36 g per pound of body weight, which might translate to approximately 56 grams every day for a 155-lb. for a sedentary man, and 46 g per day for a 130-lb. sedentary woman. However, precisely how much protein someone needs varies depending on a range of variables, such as their activity level, age and present condition of wellness, according to Healthline.

Dr. Larry Allen, director of the heart failure program at UCHealth in Aurora, Colorado, said the new analysis cannot prove that high-protein diets really induce heart failure – it might be the additional factors are responsible for the association. For instance, it is not clear whether it is protein or other things related to a high-protein diet plan, like the deficiency of certain nutrients, that could impact heart health, said Allen, who wasn’t involved in the analysis.

However, in general, the findings support the idea that a well-balanced diet, high in vegetables and whole grains,“tends to be associated with better outcomes” for heart health than an unbalanced diet, like one that is heavy in protein, Allen advises.

The American Heart Association recommends a diet which contains many different vegetables and fruits, whole grains, low-fat dairy products, fish, poultry, beans and nuts, and one that limits the intake of sweets, sugar-sweetened drinks and red meats.