Planetary Health Diet Reduces Risk of Cardiovascular Disease, CHD, Stroke, HF

The Planetary Health Diet is associated with a lower risk of overall cardiovascular disease, coronary heart disease (CHD), stroke, and heart failure (HF) among postmenopausal women, according to the results of a 20-year study.1

The Planetary Health Diet, created by the EAT-Lancet Commission in 2026, is designed to optimize human health without sacrificing the earth’s environment. The diet is structured with an expected future population of 10 billion people – to protect land and nutrition access, the diet is flexible and sustainable, focusing on whole plant foods, healthy fats, and very low amounts of animal products.2

“Our results suggest that people may not need to follow a perfect or very restrictive diet to see potential heart-health benefits,” Donya Shahamati, MS, a doctoral student in public health at the University of California, Irvine, said in a statement. “This is especially important for postmenopausal women, because cardiovascular risk increases with age and tends to rise after menopause.”1

How was the study structured?

Shahamati and colleagues analyzed data from the Women’s Health Initiative Observational Study (WHI-OS), a prospective cohort of postmenopausal women in the US. Among the women in this program, the team enrolled those with complete baseline dietary data and follow-up information through February 2025. Patients with known cardiovascular disease at baseline, implausible total energy intake, or missing dietary data or follow-up time, were excluded.1,3

The team utilized mean Planetary Health Diet Index (PHDI) as the main exposure, which was calculated via dietary intake reported on the WHI food frequency questionnaire. The team examined PHDI as both quintiles and a continuous score. These data were used to represent each patient’s alignment with the EAT-Lancet dietary recommendations. The study’s primary outcome was incident total cardiovascular disease, defined as the first occurrence of CHD, stroke, or HF. Secondary outcomes included CHD, stroke, ischemic stroke, hemorrhagic stroke, and HF.3

A total of 66,892 postmenopausal women were included in the analytic sample. Baseline PHDI scores ranged from 35-123 (mean +/- SD [standard deviation]; 75.5 +/- 10.3). Mean PHDI scores increased across all quintiles, from roughly 61 in Q1 to 90 in Q5.3

How the Diet Changed Cardiovascular Outcomes

Over a median of 19.6 years (interquartile range [IQR], 8.9-26.8), 5033 incident total cardiovascular disease events occurred. Crude incidence rates decreased across all PHDI quintiles for most outcomes; after adjusting for covariates, Shahamati and colleagues found that higher PHDI scores were associated with lower hazards of most cardiovascular disease outcomes. Total cardiovascular disease saw lower hazards from Q2 through Q5 compared with Q1 (Q2 HR, 0.86; 95% CI, 0.78-0.95; Q5 HR, 0.72; 95% CI, 0.64-0.81; P-trend <.001). This pattern remained consistent for CHD, stroke, ischemic stroke, and HF. For each 10-point higher PHDI score, the hazard was lower for total cardiovascular disease, CHD, stroke, ischemic stroke, and HF. The team did not find a statistically significant association with hemorrhagic stroke.3

Ultimately, Shahamati and colleagues determined that women in the highest PHDI quintile had a 28% lower hazard of total cardiovascular disease versus those in the lowest quintile over long-term follow-up. The team noted that these findings are generally consistent with prior longitudinal cohort studies, which found inverse associations between PHDI scores and cardiovascular disease outcomes in other populations.3

“Moving to a more plant-forward, higher-quality diet can be accomplished through small, realistic changes,” Shahamati said in a statement. “These changes might include filling half the plate with vegetables more often; using avocado or olive oil in place of butter; choosing oatmeal or whole-grain cereal for breakfast; or trying a meatless meal once per week.”1

References

1. American Society for Nutrition. Plant-forward planetary health diet linked to lower heart disease risk. Eurekalert! July 25, 2026. Accessed July 31, 2026. https://www.eurekalert.org/news-releases/1136409

2. Roeder A. Planetary Health Diet: Better for you, better for the planet. Harvard T.H. Chan. September 12, 2024. Accessed July 31, 2026. https://hsph.harvard.edu/news/planetary-health-diet-better-for-you-better-for-the-planet/

3. Shahamati D, Yang B, Liu S, et al. Association between the Planetary Health Diet Index and risk of cardiovascular diseases in postmenopausal women: Findings from the Women’s Health Initiative Observational Study. American Journal of Preventive Cardiology. Published online July 17, 2026:101750. doi:10.1016/j.ajpc.2026.101750