Aug. 9, 2021 -- A new study finds a link between eating plant-based foods rich in certain nutrients and a lower risk of heart disease.

The study, which observed more than 200,000 men and women over 30 years, shows that those who regularly ate more plant-based foods rich in what are known as lignans had a much lower risk of developing coronary heart disease than those who did not.

Plant-based foods such as whole grains, fruits, vegetables, seeds, nuts, red wine, and coffee contain lignans, molecules that have antioxidant and anti-inflammatory effects, explains Yang Hu, a research fellow at the Harvard T.H. Chan School of Public Health in Boston.

"Lignan is an estrogen-like molecule, so it exerts some estrogenic effects which are cardioprotective. It also has ant-inflammatory properties," Hu says.

Hu and his team studied data on eating patterns of more than 200,000 men and women who were free of heart disease and cancer at the beginning of the observation period. Food frequency questionnaires were filled out every 2 years and how many lignan-rich foods they ate was tracked.

Over time, the researchers found a significantly reduced risk of coronary heart disease among those who ate more plant-based foods rich in lignans. This was true for both men and women, and for various types of lignans.

The study also showed that when fiber was added to the diet, the protective association with diets higher in the lignan-rich plant foods was increased.

Participants with higher lignan intake were older, fitter, leaner, and had were less likely to have high blood pressure and high cholesterol.

Hu plans to take his research further to explore why fiber may help lignan molecules create their protective benefits..

The makeup of your gut matters, too, Hu says, because the lignans must go through the gut bacteria to reach the blood system.

"This opens another avenue of research because we can take further steps to see how the gut microbiota and fiber interact with the production of lignans and how these might affect disease risk for other conditions, such as diabetes." he added.

Nutrition expert David J.A. Jenkins, MD, professor of Medicine and Nutritional Sciences at the University of Toronto, who authored an editorial that appeared with the publication, says these new findings reaffirm the value of eating a variety of plant foods.

Jenkins also advocates eating such foods in a less-processed form, because they have higher amounts of their antioxidant, anti-inflammatory compounds.

"You are far better off eating your apple than having apple juice, and you’re far better off having your banana than making it into a smoothie," he says.