High-protein diets are associated with a somewhat higher risk for heart failure in middle-aged men, according to a study from the University of Eastern Finland published by the American Heart Association. The study followed 2,682 men ages 42 to 60 and reexamined them at 4, 11 and 20 years after baseline examinations conducted in the 1980s.
- Comparing men who ate the highest amount of protein with those who consumed the least, researchers found heart disease risk was greatest for those eating dairy-based protein (49%), followed by animal protein (43%), all protein sources (33%) and plant-based protein (17%). Only protein from fish and eggs was not associated with a higher risk, the study found.
"As this is one of the first studies reporting on the association between dietary protein and heart failure risk, more research is needed before we know whether moderating protein intake may be beneficial in the prevention of heart failure," Heli E.K. Virtanen, first author of the study and a Ph.D. student and early career researcher at the University of Eastern Finland in Kuopio, said in a release.
Given that high-protein diets — such as paleo or ketogenic — are so popular today, it's surprising there haven't been more evaluations of how protein intake affects the risk of heart failure. Yet the Finnish researchers were clear in their conclusion: "High protein intake may not be the optimal dietary strategy in the prevention of heart failure."
Also surprising is that plant-based diets, which people adopt for their health and other reasons, were associated with a slightly higher risk of heart failure — although those diets were assigned the lowest risk level except for protein from fish and eggs.
Food manufacturers might want to track such studies and make sure they aren't advocating protein sources which are not heart-healthy. For those whose protein products are fish-based, egg-based or plant-based, it could be helpful to note in marketing outreach that those sources have been found to have no or low association with risk of heart disease.
The meat and dairy industries emphasize animal-based protein sources for adequate protein intake, but their products showed the highest correlation with heart failure risk in the Finnish study. With dairy-based protein sources at the top of the list, that already challenged industry now has another issue to confront — especially because ingredients manufacturers are hoping to capitalize on whey protein, a natural byproduct of dairy processing practices.
Americans know they need protein, but they may not know how much or the best sources. The Recommended Dietary Allowance for protein is 0.8 grams per kilogram of body weight — considered the minimum to meet basic nutritional requirements. The level varies by gender, age, height, weight and activity level, so the U.S. Department of Agriculture has posted a calculator to assess individual requirements for protein and other nutrients. It may help people more likely to follow personalized nutrition plans to find out how much protein they really need and adjust their intake accordingly.
Protein is currently one of the hottest trends in food. Brands are adding protein to all sorts of products, from chips to chocolate milk to snack cakes, hoping to be seen as both functional and delicious.
The findings from this study may have small impact unless they're widely publicized by the American Heart Association, food manufacturers and media outlets. Chances are it will take more than that to get consumers to change their eating habits.