Plant-based diets that include lots of sweets and refined grains could increase the risk of heart disease, a new Harvard University study found.
Previous research on the impact of plant-based diets treated plant foods equally, even though some such as refined grains and sugar-sweetened beverages are associated with a higher risk of heart disease.
In the new study, the researchers created three versions of a plant-based diet: an overall plant-based diet consisting of of all plant food and reduced animal food intake; a diet that consisted of healthy plant foods such as whole grains, fruits and vegetables; and a plant-based diet consisting of less healthy plant foods such as refined grains.
Researchers used a baseline sample of 73,710 women from the Nurses’ Health Study, 92,320 women from the Nurses’ Health Study 2, and 43,259 men from the Health Professionals Follow-Up Study. Participants with coronary heart disease at baseline were excluded along with those with cancer, stroke, and coronary artery surgery.
The research showed that 8,631 participants developed coronary heart disease. A higher intake of a more healthy plant-based diet rich in whole grains, fruits, and vegetables, was associated with a substantially lower risk of heart disease. But a plant-based diet that emphasized less healthy plant foods like sweetened beverages, refined grains, potatoes and sweets had the opposite effect, the study found.
“It’s apparent that there is a wide variation in the nutritional quality of plant foods, making it crucial to take into consideration the quality of foods in a plant-based diet,”said Ambika Satija, a postdoctoral fellow at the Harvard University School of Public Health and the study’s lead author.
The study was published in the Journal of the American College of Cardiology.
Source: American College of Cardiology