Eating A Plant-Based Diet May Lower The Risk Of Heart Disease In Mid-Life

Photo by Mariana Montes de Oca on Unsplash

Eating nutritious, plant-based foods is downright heart-healthy according to two research studies published this month in the Journal of the American Heart Association.

Both studies analyzed healthy plant food consumption, and researchers found that both young adults and postmenopausal women who ate more healthy plant-based foods had fewer heart attacks and were less likely to develop heart disease.

The American Heart Association Diet and Lifestyle Recommendations suggest that a healthy diet stressing a variety of fruits and vegetables, whole grains, low-fat dairy products, skinless poultry and fish, nuts and legumes, and non-tropical vegetable oils is ideal. It also counsels people to limit their consumption of saturated fat, trans fat, sodium, red meat, and high-sucrose snacks and beverages.

One study, titled "A Plant-Centered Diet and Risk of Incident Cardiovascular Disease during Young to Middle Adulthood," looked at how long-term consumption of a plant-based diet starting in young adulthood is associated with a lower risk of cardiovascular disease in midlife.

"Earlier research was focused on single nutrients or single foods, yet there is little data about a plant-centered diet and the long-term risk of cardiovascular disease," said Yuni Choi, Ph.D., lead author of the young adult study at the University of Minnesota School of Public Health.

Choi and colleagues studied 4,946 adults who were 18- to 30-years-old at the time of enrollment (1985-1986) and without any sign of cardiovascular disease. Participants had follow-up exams from 1987 to 2016. Participants were not instructed to eat certain things so the researchers could collect unbiased, long-term habitual data.

After detailed diet history interviews, the quality of the participants' diets was scored. Based on their known data relationship with cardiovascular disease, food groups were classified into three groups:
   1. beneficial foods (such as fruits, vegetables, beans, nuts and whole grains);
   2. adverse foods (such as fried potatoes, high-fat red meat, salty snacks, pastries and soft drinks); and
   3. neutral foods (such as potatoes, refined grains, lean meats and shellfish).

Participants who received higher scores ate a variety of beneficial foods, while people who had lower scores ate more adverse foods. Overall, higher values went to the nutritionally rich, plant-centered diets.

"As opposed to existing diet quality scores that are usually based on small numbers of food groups, APDQS is explicit in capturing the overall quality of diet using 46 individual food groups, describing the whole diet that the general population commonly consumes. Our scoring is very comprehensive, and it has many similarities with diets from the U.S. Department of Agriculture's Food and Nutrition Service, the DASH (Dietary Approaches to Stop Hypertension) diet, and the Mediterranean diet."
David E. Jacobs Jr., Ph.D., senior author of the study and Mayo Professor of Public Health at the University of Minnesota.

Researchers found that people who scored in the top 20% on the long-term diet quality score were less likely to develop cardiovascular disease.

"A nutritionally rich, plant-centered diet is beneficial for cardiovascular health. A plant-centered diet is not necessarily vegetarian," Choi said. "People can choose among plant foods that are as close to natural as possible, not highly processed. We think that individuals can include animal products in moderation from time to time, such as non-fried poultry, non-fried fish, eggs and low-fat dairy."

The "Portfolio Diet," as it's known, includes nuts; plant protein from soy, beans, or tofu; fiber from oats, barley, okra, eggplant, oranges, apples, and berries; and monounsaturated fats found in olive and canola oil and avocadoes. Trials had demonstrated that the Portfolio Diet resulted in significant lowering of "bad" cholesterol or LDL-C, more so than a traditional low-saturated-fat diet in one study and tied with taking a cholesterol-lowering statin medication in another.

The study focused on whether postmenopausal women who followed the Portfolio Diet experienced fewer heart disease events. The study included 123,330 women who enrolled between 1993 and 1998, between 50-79 years old, and without any sign of cardiovascular disease. The study group was followed until 2017.

The researchers found that compared to women who followed the Portfolio Diet less frequently, those with the closest alignment were 11% less likely to develop any type of cardiovascular disease, 14% less likely to develop coronary heart disease, and 17% less likely to develop heart failure.

"These results present an important opportunity, as there is still room for people to incorporate more cholesterol-lowering plant foods into their diets. With even greater adherence to the Portfolio dietary pattern, one would expect an association with even fewer cardiovascular events, perhaps as much as cholesterol-lowering medications. Still, an 11% reduction is clinically meaningful and would meet anyone's minimum threshold for a benefit. The results indicate the Portfolio Diet yields heart-health benefits," said John Sievenpiper, M.D., Ph.D., senior author of the study at St. Michael's Hospital in Toronto and associate professor at the University of Toronto.

"We also found a dose-response in our study, meaning that you can start small, adding one component of the Portfolio Diet at a time, and gain more heart-health benefits as you add more components," said Andrea J. Glenn, M.Sc., R.D., a lead author of the study at St. Michael's Hospital in Toronto.

The researchers note that while the study was observational and cannot directly establish a cause-and-effect relationship between diet and cardiovascular events, they are very hopeful. If nothing else, it may provide the most reliable estimate for the diet-heart relation to date. Nevertheless, all of the researchers stipulate that these findings need to be further investigated in additional populations.

Author

Dr. Mark L. Meyer Dr. Meyer graduated from Haverford College with a Bachelor of Science, High Honors, in cellular and molecular biology, Phi Beta Kappa, Magna Cum Laude. He attended the Yale University School of Medicine, where he also completed a categorical residency in Internal Medicine, served for one year as an Emergency Department attending physician, and held the title of Clinical Instructor in the Department of Surgery. During this time, Dr. Meyer obtained a J.D. from the Yale Law School, concentrating on medical ethics, scientific research law, and FDA law. He then completed a fellowship in Cardiovascular Diseases at the Hospital of the University of Pennsylvania, where he obtained Level 3 Nuclear Cardiology training.