As more people are advised to shun meat, a new study from Australia adds to evidence that a vegetarian diet can help improve heart health.
A review of 20 prior investigations found that folks who followed a vegetarian diet for six months, on average, saw improvements in cholesterol, blood sugar and body weight.
The study analysis "provides support to the current knowledge that eating more plant foods, fewer animal foods or lean, low-fat animal foods is a supporter of health,"said Connie Diekman, a food and nutrition consultant and former president of the U.S. Academy of Nutrition and Dietetics.
Another expert, who was also not involved with the study, agreed.
"The research is pretty clear and consistent that eating more plant foods is good for heart health, while reducing meat and processed meats,"seconded Lona Sandon, program director of clinical nutrition with the School of Health Professions at UT Southwestern Medical Center in Dallas.
Vegetarian diets are increasingly recommended for the general population, but it wasn't known if they would benefit people with current or predicted heart issues, said study leader Tian Wang and colleagues. Wang is a registered dietitian and doctoral student at the University of Sydney.
Their meta-analysis of prior research tracked nearly 1,900 adults in all. The average age of patients in each of the studies ranged from 28 to 64, with studies running from two months to two years.
All the investigations were published in the United States, Europe, Asia or New Zealand between 1990 and 2021. All participants had heart disease or were deemed high-risk for future disease.
Four studies focused on patients who already had heart disease, while seven focused on patients with diabetes. Nine of the studies included patients with at least two risk factors for future heart disease.
Diets varied across the studies. In some instances, patients consumed low-fat, animal-free vegan meal plans. In other investigations, diets were categorized as vegetarian while also including nonfat dairy and egg whites.
Overall, the researchers determined that compared with following a meat-inclusive diet, consuming a vegetarian diet had a "modest but significant effect"in helping keep cholesterol, blood sugar and body weight in check. However, no statistically significant impact on blood pressure control was observed.
The findings appear in the July 25 issue of JAMA Network Open.
Wang's team also called for more research to further examine how vegetarian diets might affect heart heath when combined with prescribed medications.
But for Sandon, the jury is already in.
"High-risk patients need to do everything they can, as sometime medications are not enough,"she noted. "Eating a diet higher in plant foods is part of the puzzle.
"Plant foods help keep arteries clean and flexible. Compounds such as flavan-3-ols -- found in foods such as berries, tea and cocoa -- help keep the cells of the arteries healthy and functioning normally," Sandon added.
What's more, "there is little to no risk of adding more fruits, vegetables, nuts, seeds, legumes and healthy oils to your daily diet,"she stressed. "The fiber and phytonutrients that come along with a plant-focused diet aid in gut health and heart health."
Diekman agreed.
Noting heart disease is "the No. 1 killer of people worldwide,"she said that "evidence continues to show that the nutrient package of plant foods, and their diverse phytonutrient content, are positive supporters of heart health."
In addition, Diekman said, plant foods contain less saturated fat, which can increase LDL-C, the bad cholesterol, thus making limitation of animal foods, and a focus on more plant foods, a positive step to reduce the potential risk of heart disease.
"As a registered dietitian," she added, "my guidance to my clients is to develop an eating plan that is enjoyable, maintainable, and that is built around plant foods, with smaller amounts of lean or low-fat animals."
More information
There's more on the link between a vegetarian diet and improved heart health at the American Heart Association.
SOURCES: Connie Diekman, M.Ed., RD, LD, FADA, FAND, food and nutrition consultant and former president, Academy of Nutrition and Dietetics; Lona Sandon, PhD, RDN, LD, FAND, program director and associate professor, Department of Clinical Nutrition, School of Health Professions, UT Southwestern Medical Center, Dallas; JAMA Network Open, July 25, 2023