Plant-based diet found to cut the risk of developing heart disease

15 Nov 2017 --- Eating a mostly plant-based diet was associated with less risk of developing heart failure among people without previously diagnosed heart disease or heart failure, according to preliminary research presented at the American Heart Association’s Scientific Sessions 2017 event for global advances in cardiovascular science.

Heart failure – a chronic, progressive condition in which the heart muscle is unable to pump enough blood to maintain its workload – affects about 6.5 million adults over age 20 in the US, according to the American Heart Association.

“Our study looked at what people in the US tended to eat, which means that each participant received a score for each of the dietary patterns (which included animal protein),” Kyla Lara, M.D., first author of the study and an internal medicine resident at Icahn School of Medicine at Mount Sinai Hospital in New York, US, tells NutritionInsight. “Our findings showed that participants who mostly adhered to the plant-based dietary pattern had a decreased risk for heart failure.”

“Eating a diet mostly [consisting] of dark green leafy plants, fruits, beans, whole grains and fish, while limiting processed meats, saturated fats, trans fats, refined carbohydrates and foods high in added sugars is a heart-healthy lifestyle and may specifically help prevent heart failure if you don't already have it,” summarizes Lara.

Heart risk decreases by 42 percent
The study looked at five different dietary patterns and, according to the author, found that people who ate a plant-based diet most of the time had a 42 percent decreased risk of developing heart failure over the four years of the study, compared with people who ate fewer plant-based foods. Other dietary patterns – described as convenience, sweets, Southern or alcohol/salads style – were not associated with a decreased risk for heart failure.

Previous studies had shown that what people eat can play an important role in increasing or decreasing the risk of atherosclerosis, the slow narrowing of the arteries that underlies heart attacks, most strokes and heart failure. This study focused specifically on whether diet can influence the development of heart failure among people with no diagnosed heart disease.

The researchers used data collected for the Reasons for Geographic and Racial Differences in Stroke (REGARDS), a nationwide observational study of risk factors for stroke in adults 45 years or older sponsored by the National Institutes of Health.

The participants, who were recruited from 2003 to 2007 and followed through 2013, included 15,569 patients without known coronary artery disease or heart failure. Incidents of heart failure within this group were confirmed by health care providers. Over the nearly 3,000 days of follow up, 300 instances of hospitalizations for incident heart failure were reported.

Participants in the REGARDS study reported their diets using a food frequency questionnaire, a standard method for classifying diets that uses statistical modeling to assign a person’s diet to one of five dietary patterns:

• Convenience (red meats, pastas, fried potatoes, fast foods).
• Plant-based (dark, leafy vegetables, fruits, beans, fish).
• Sweets (desserts, breads, sweet breakfast foods, chocolate, candy).
• Southern (eggs, fried food, organ meats, processed meats, sugar-sweetened beverages).
• Alcohol/Salads (salad dressings, green, leafy vegetables, tomatoes, wine, butter, liquor).

The researchers found that of the five dietary patterns, greater adherence to the plant-based diet had the strongest association with a decreased risk of incident heart failure when adjusted for age, sex and race of the participants and for other risk factors. No associations for the other four dietary patterns were found.

The study was observational, which means it can identify a trend or association, but cannot prove cause and effect, the American Heart Association notes. Lara adds that a useful follow-up study would involve determining the mechanism for the plant-based diet and its protective role in heart disease.

Overall, the American Heart Association recommends a dietary pattern that includes a variety of fruits and vegetables, whole grains, low-fat dairy products, poultry, fish, beans, non-tropical vegetable oils, and nuts. Limiting intake of sweets, sugar-sweetened beverages and red meats is also recommended.