If you’re a reader of this website, then you are probably aware of the importance of eating a balanced diet consisting of healthy carbohydrates, beneficial fats, and an adequate amount of protein. But when it comes to protein, some of us are accustomed to thinking immediately of animal sources. However, new research shows that getting our protein from plants rather than animals might be a better approach for long-term health.

The study, which took place at Massachusetts General Hospital and Harvard Medical School in Boston, found that consuming more protein from plant sources and less from animal sources is associated with a longer lifespan and may even provide some protection from risk factors such as frequent alcohol use and being overweight.¹Song, Mingyang; et al. “Association of Animal and Plant Protein Intake With All-Cause and Cause-Specific Mortality.” JAMA Internal Medicine. 1 August 2016. Accessed 3 August 2016. http://archinte.jamanetwork.com/article.aspx?articleid=2540540. The subjects were 131,342 nurses and other health care workers. When the investigation began, the average age among participants was 49 and the majority of them were women.

They were tracked between 1980 and 2012, for a total of more than 30 years. The volunteers regularly completed questionnaires on the types of foods they were eating. Using this information, the scientists determined that the median intake of their calories from animal protein was 14 percent and the median intake of their calories from plant protein was four percent.

By the time the research had concluded, roughly 36,000 of the subjects had died. The two main causes of mortality were cancer, responsible for approximately 13,000 of the deaths, and cardiovascular disease, responsible for about 8,850 of the deaths.

The investigators then analyzed the data on mortality and the eating patterns of each of the participants. They discovered that every three percent increase in calories derived from plant protein was linked to a 10 percent reduction in risk of death. What’s more, every 10 percent rise in the percentage of calories coming from animal protein was tied to a two percent greater risk of mortality from any cause and an eight percent higher risk of mortality from cardiovascular disease in particular. And these results held up even after the researchers controlled for a variety of factors including obesity, a sedentary lifestyle, smoking, and alcohol use.

Perhaps not surprisingly, the advantages conferred by eating higher amounts of plant protein were not as strong in those with healthier lifestyle habits in general. Instead, the participants who were less healthy due to obesity, heavy consumption of alcohol, or other factors appear to have received greater protection from a larger intake of plant protein. It’s not clear exactly why this is the case, but it could be due to plant protein counteracting some of the negative physical effects of their behaviors such as inflammation. Or it could be that simply removing a notable risk factor from your lifestyle matters more if you’re not doing anything positive to counteract your bad habits.

The study was not designed to prove cause and effect, but it certainly showed an association between consuming more plant protein and longevity. And let’s not forget that there is a big difference between the various sources of animal protein. Eating processed meats has been linked to pancreatic cancer in a 2012 study at the Karolinska Institute in Stockholm, Sweden,²Larsson, SC and Wolk, A. “Red and processed meat consumption and risk of pancreatic cancer: meta-analysis of prospective studies.” British Journal of Cancer. 31 January 2012. Accessed 4 August 2016. http://www.ncbi.nlm.nih.gov/pubmed/22240790. and the meats found in most supermarkets are full of growth hormones and other chemicals.

If you want to consume meat as a protein source, just do it wisely. Look for organic, grass-fed beef and cage-free poultry, and keep your portions down to three ounces a day or less. Fish is a healthier source of protein than meat, as long as you don’t overdo it on those high in mercury such as swordfish and king mackerel. To learn more about dietary protein, check out Jon Barron’s series beginning with Protein, Part 1.

Ultimately, we can all benefit from finding more sources of plant protein to incorporate into our diets on a daily basis. Consider eating nuts as an afternoon snack (if you don’t have allergies), adding beans to your meals, making a side dish of peas, and trying out some tofu recipes. Just don’t use eating plant protein as an excuse for inactivity and other bad habits. Remember, as the study showed, the more good things you do to maintain an all-around fit lifestyle, the better your body is able to counteract the bad things, thus helping you lead a long and healthy life.