The Real Secret to Living to 100? Plants, According to the Largest Diet Study Yet

black woman taking a bite of vegan foodAmidst contentious debates and conflicting advice about the health risks and benefits of various diets, a new study makes a strong case for plant-based eating as a means of living a healthier, longer life.

Largest Study Ever Points to Plant-Based Eating as a Longevity Booster 

The study, published in the JAMA Internal Medicine Journal and carried out by scientists at Massachusetts General Hospital, was the largest ever to examine how different sources of dietary protein affect longevity. Conclusions were based on over three decades of health and diet records from over 130,000 people.

The Massachusetts General researchers specifically looked at the percentage of plant protein versus animal protein in participants’ diets. They discovered that participants who ate more animal protein were more likely to have died during the decades covered by the study, while participants who ate more plant protein were more likely to still be living.

The data used by the Massachusetts General researchers came from two long-term studies—the Nurse’s Health Study (NHS) and the Health Professionals Follow-up Study (HPFS). All told, the researchers analyzed more than 3.5 million person-years of information. Over 36,000 deaths occurred among study participants: approximately 9,000 from cardiovascular disease, 13,000 from cancer, and 14,000 from other causes.

Plant Protein Helps, Animal Protein Hurts

The researchers found that for every 3% increase in calories from plant protein, a participant’s risk of death from various lifestyle factors decreased by 10%. Risk of dying from heart disease, in particular, decreased by as much as 12%.carrots being swept off a cutting board into a bowel of vegetables

Animal protein had nearly the opposite effect: a 10% increase in animal protein intake elevated participants’ risk of death from all causes by 2%, and risk of death from heart disease by 8%!

“Overall, our findings support the importance of the sources of dietary protein for long-term health outcomes,” said lead scientist Dr. Mingyang Song, in a press release published alongside the study. “People should consider eating more plant proteins than animal proteins,” Song stated.

The Effects of Social And Environmental Factors

The researchers noted that it’s important to consider how complex social and environmental factors play into the study’s results. For instance, vegans may be more likely to come from socially affluent backgrounds, a known influence on lifespan. The researchers also found that individuals who mentioned unhealthy activities such as smoking or drinking heavily experience a magnified risk of adverse health outcomes from increased animal protein intake.

For participants with exemplary health habits, in fact, the association between animal protein intake and increased risk of death virtually disappeared! “When we looked deeper into the data,” said Dr. Song, “we found that—at similar levels of animal protein intake—those in the healthy lifestyle group consumed primarily fish and poultry and limited to no red meats, high-fat dairy, and eggs.” They believe the divide between the types of animal proteins favored by those with unhealthy lifestyle habits and those with healthy lifestyle habits explains their divergent lifespan predictions.

Choose Plant-Based Eating for Long-Term Health

Even when taking social and environmental factors into account, the researchers found that that a person’s choice of protein sources strongly impacted their long-term health. “Our findings suggest people should consider eating more plant proteins than animal proteins,” Dr. Song said, “and when they do choose among sources of animal protein, fish and chicken are probably better choices.”

Song and his fellow researchers hope future studies will examine the mechanisms underlying the different effects of plant and animal proteins on human health. We’d certainly be curious to read about what they uncover!