Eating a diet with a higher proportion of plant-based protein compared to animal protein may reduce the risk of cardiovascular disease (CVD) and coronary heart disease (CHD). This is evidenced by a new study published in the American Journal of Clinical Nutrition, led by scientists at the Harvard T.H. Chan School of Public Health.
While global dietary guidelines recommend higher plant protein intake, the ideal ratio between plant and animal protein remains unclear. This is the first study to explore this ratio and its impact on health, particularly heart health.
Eating More Plant-Based Protein Helps Reduce Heart Disease Risk Researchers used 30 years of data on diet, lifestyle, and heart health from nearly 203,000 men and women involved in the Nurses’ Health Study I and II and the Health Professionals Follow-Up Study. Participants reported their protein intake every four years.
They calculated the total protein intake of each participant, measured in grams per day, as well as the specific amounts of animal and plant-based protein they consumed. During the study, 16,118 cases of CVD were recorded, including over 10,000 cases of CHD and more than 6,000 cases of stroke.
After adjusting for participants’ health history, demographic factors, and lifestyle, the study found that consuming more plant-based protein rather than animal protein was associated with a lower risk of CVD and CHD.
Compared to participants with the lowest ratio of plant to animal protein intake (about 1:4.2), those with the highest ratio (about 1:1.3) had a 19% lower risk of CVD and a 27% lower risk of CHD. These risk reductions were even higher among those who consumed more protein overall.
Those who consumed the most protein (21% of energy from protein) and followed a higher plant-to-animal protein ratio had a 28% lower risk of CVD and a 36% lower risk of CHD compared to those with the lowest protein intake (16% of energy).
No significant link was found between stroke risk and this ratio. However, replacing red and processed meats with some plant-based sources, such as nuts, showed a lower stroke risk.
The researchers also examined whether there was a point at which eating more plant-based protein would no longer provide additional benefits or might even have negative effects. They found that the risk reduction for CVD began to level off at a ratio of 1:2, but the risk of CHD continued to decrease with a higher plant-to-animal protein ratio.
According to the researchers, these reduced risks could be due to replacing red and processed meats with some plant-based protein sources, particularly nuts and legumes. Such substitutions have been found to improve metabolic cardiovascular risk factors, including blood lipids, blood pressure, and inflammatory biomarkers. This is partly because plant proteins often come with higher fiber, antioxidant vitamins, minerals, and healthy fats.
The researchers also noted that the ratio they identified is an estimate and further research is needed to determine the optimal balance between plant and animal protein. Additionally, further studies are needed to determine how stroke risk may be influenced by protein intake.
The Best Diet to Fight Heart Disease According to the American Heart Association, a healthy diet is one of the best ways to fight heart disease. What we eat can affect other modifiable risk factors, such as cholesterol, blood pressure, diabetes, and weight.
To maintain a healthy weight, people need to consume calories that match the amount of calories burned through normal metabolic processes and physical activity.
Choose nutrient-dense foods that contain vitamins, minerals, fiber, and other nutrients but fewer calories compared to nutrient-poor foods. Eat plenty of vegetables, fruits, and whole grains.
Additionally, include low-fat dairy products, plant-based proteins, fish, poultry, legumes, and nuts. Limit intake of saturated fats, trans fats, sodium, sweets, sugary drinks, and red meats.
