UNIVERSITY PARK, Pa. — Staying away from meat, nuts, dairy, and soy may not be super fun from a taste perspective, but a new study by researchers at Pennsylvania State University finds avoiding protein may be the key to avoiding heart disease.
Protein-rich foods contain sulfur amino acids. The research team discovered that diets low in sulfur amino acids are associated with a lower risk of developing cardiovascular disease. It’s estimated that the average American consumes two-and-a-half times the estimated requirement of sulfur amino acids.
In the right amount, sulfur amino acids are very beneficial. They help maintain one’s metabolism and overall health.
“For decades it has been understood that diets restricting sulfur amino acids were beneficial for longevity in animals,” says John Richie, a professor of public health sciences at Penn State’s College of Medicine, in a release. “This study provides the first epidemiologic evidence that excessive dietary intake of sulfur amino acids may be related to chronic disease outcomes in humans.”
The diets and blood of more than 11,000 people were analyzed for this study. People who ate foods with less sulfur amino acids displayed a much lower risk of developing heart disease based on their blood work. More specifically, researchers calculated a composite cardiometabolic disease risk score based on observed biomarkers in participants’ blood after engaging in a 10-16 hour fast. These biomarkers included cholesterol, glucose, triglycerides, and insulin.
“These biomarkers are indicative of an individual’s risk for disease, just as high cholesterol levels are a risk factor for cardiovascular disease,” Richie adds. “Many of these levels can be impacted by a person’s longer-term dietary habits leading up to the test.”
Meanwhile, diets were tracked via in-person daily recalls.
For a person weighing 132 pounds, just two ounces of chicken breast would meet the estimated average daily requirement for sulfur amino acids according to the Food and Nutrition Board of the National Academy of Medicine. Other food choices such as one egg, half an avocado, or a cup of brown rice would all singularly meet the requirement as well.
“Many people in the United States consume a diet rich in meat and dairy products and the estimated average requirement is only expected to meet the needs of half of healthy individuals,” comments study co-author Xiang Gao, an associate professor and director of the nutritional epidemiology lab at the university. “Therefore, it is not surprising that many are surpassing the average requirement when considering these foods contain higher amounts of sulfur amino acids.”
Even after accounting for possible confounding factors like age, sex, and medical history, researchers noted that a high sulfur amino acid intake was associated with a higher composite cardiometabolic risk score. Grains, fruits, and vegetables are the food sources lowest in sulfur amino acids.
“Meats and other high-protein foods are generally higher in sulfur amino acid content,” says Zhen Dong, the study’s lead author and a College of Medicine graduate. “People who eat lots of plant-based products like fruits and vegetables will consume lower amounts of sulfur amino acids. These results support some of the beneficial health effects observed in those who eat vegan or other plant-based diets.”
This study didn’t actually track participants over a long period of time to see if they ended up developing heart problems, so the study’s authors would like to see a more extensive long-term study performed on this topic.
“Here we saw an observed association between certain dietary habits and higher levels of blood biomarkers that put a person at risk for cardiometabolic diseases,” Richie concludes. “A longitudinal study would allow us to analyze whether people who eat a certain way do end up developing the diseases these biomarkers indicate a risk for.”
The study is published in Lancet EClinical Medicine.