Planetary health diet study ties plant-forward eating to lower heart risk
A 20-year Women's Health Initiative analysis linked closer adherence to the diet with lower cardiovascular risk in postmenopausal women.
By Tom Brennan · Health & Medicine Correspondent
3 min read
A 20-year planetary health diet study of 66,892 postmenopausal women found that those whose eating patterns most closely matched the plant-forward plan had lower cardiovascular disease risk, researchers reported. The finding matters because cardiovascular risk rises with age and tends to increase after menopause, according to Donya Shahamati, a doctoral student in public health at the University of California, Irvine.
The research, published in the American Journal of Preventive Cardiology, used data from the Women's Health Initiative. Shahamati is scheduled to present the findings at NUTRITION 2026, the American Society for Nutrition's annual meeting in National Harbor, Maryland, held July 25-28.
Women in the highest-adherence group had about a 28% lower risk of cardiovascular disease than women whose diets least resembled the Planetary Health Diet, the researchers found. The analysis also linked closer adherence with lower risk of coronary heart disease, stroke and heart failure.
What is the planetary health diet?
The Planetary Health Diet is a plant-forward eating pattern that emphasizes fruits, vegetables, whole grains, legumes, nuts and unsaturated fats. It limits red and processed meats, added sugars, refined grains and saturated fats, according to the researchers.
Shahamati said the results point to possible heart-health benefits without requiring a perfect or highly restrictive diet. She said people could move toward the pattern through practical swaps, such as eating more vegetables, using avocado or olive oil instead of butter, choosing oatmeal or whole-grain cereal, or having a meatless meal once a week.
How was the planetary health diet study done?
The investigators studied Women's Health Initiative participants who had no cardiovascular disease at the start of the analysis, between 1994 and 1998. The women, whose average age was about 63 at the beginning, also had complete diet, health and lifestyle information available for the study.
Researchers used a food frequency questionnaire collected at the start to calculate each participant's Planetary Health Diet Index score. Higher scores meant a woman's diet was more closely aligned with the Planetary Health Diet, and the team sorted participants into five groups based on those scores.
The women were followed for about two decades to track who developed cardiovascular disease. In the analysis, the researchers adjusted for factors that could affect heart risk, including age, race and ethnicity, education, income, smoking, alcohol use, physical activity, body mass index and total calorie intake.
Shahamati said the team examined overall cardiovascular disease and also looked separately at coronary heart disease, stroke and heart failure. The researchers reported that the pattern of lower risk was seen across those cardiovascular outcomes.
The study also found that moderate adherence was associated with lower risk, not only the highest level of adherence. Each 10-point increase in the Planetary Health Diet Index score was linked to additional risk reduction, the researchers reported.
The authors cautioned that the study was observational, so it cannot prove that the diet directly caused the lower cardiovascular risk. The research team is also studying diet quality over time in older adults to better understand healthy aging and chronic disease prevention, according to the American Society for Nutrition.
This story draws on original reporting from Medical Xpress.