Live Longer and Healthier By Eating More Plant Protein and Less Meat Protein, Study Reveals

The largest study of its kind to examine the effects of different sources of dietary protein found that a high intake of protein from animal sources, particularly processed and unprocessed red meats, was associated with a higher death rate. Compared with a high intake of protein from plant sources, including food like breads, cereals, pasta, beans, nuts and legumes, which was associated with a lower risk of mortality.

 

The study’s results are published in JAMA Internal Medicine. It was carried out by researchers from a variety of institutions in the US and Italy including Massachusetts General Hospital.

 

The researchers analyzed more than 30 years of data for NHS participants and 26 years of data totaling more than 3.5 million person-years. Over this time, there were more than 36,000 deaths from cardiovascular disease, approximately 13,000 from cancer and around 14,000 from other causes.

 

Closer analysis revealed that the association of animal protein intake with an elevated mortality risk only applied to people with at least one factor associated with an unhealthy lifestyle such as being obese, underweight, heavy alcohol consumption, history of smoking or physical inactivity.

 

“Overall, our findings support the importance of the sources of dietary protein for long-term health outcomes,” says Mingyang Song, a research fellow in the Massachusetts General Hospital Clinical and Translational Epidemiology Unit and corresponding author of the report.”

 

“While previous studies have primarily focused on the overall amount of protein intake, which is important, from a broad dietary perspective, the particular foods that people consume to get protein are equally important.”

 

“Our findings also have public health implications and can help refine current dietary recommendations about protein intake, in light of the fact that it is not only the amount of protein but specific food sources that is critical for long-term health.”

 

While several studies have suggested that substituting proteins for carbohydrates in the diet have health benefits like weight management, reducing blood pressure and other cardiovascular factors, the authors note that there are few studies to have examined the specific sources of protein.

 

The current study used data from two previous studies which have compiled comprehensive data on more than 170,000 participants since the 1980s. Participants completed health questionnaires every two years and provided information on their dietary intake.

 

In addition to the benefits associated with plant protein, each 10 percent increase in the proportion of calories from animal protein was associated with a two percent higher risk of death and an eight percent increased risk of death from cardiovascular disease.

 

“While we expected we might find the associations to be weaker in the healthy lifestyle group, we did not expect them to completely disappear,” adds Song. “But when we looked deeper into the data, we found that, at similar levels of animal protein intake, those in the unhealthy lifestyle group consumer more fish and poultry. So we suspect the different sources of animal protein between the two groups may contribute to the stronger results in the unhealthy lifestyle group.”

 

“Our findings suggest that people should consider eating more plant proteins than animal proteins, and when they do choose among sources of animal protein, fish and chicken are probably the better choices.”

 

“Future studies should examine the mechanisms underlying the different effects of plant and animal proteins, along with different sources of animal proteins, on overall health.”