A new study by Harvard T.H. Chan School of Public Health highlights the substantial benefits of the Planetary Health Diet (PHD). This diet, which emphasizes minimally processed plant foods and allows modest consumption of meat and dairy, is found to reduce the risk of premature death by approximately 30% and significantly lower environmental impacts.
The study, published online in The American Journal of Clinical Nutrition on June 10, is the first large-scale evaluation of the recommendations from the 2019 EAT-Lancet report. Researchers named the dietary pattern the Planetary Health Diet (PHD).
Long-term adherence and environmental impact
The study analyzed health data from more than 200,000 individuals enrolled in the Nurses’ Health Study I and II, along with the Health Professionals Follow-Up Study. These participants, initially free of major chronic illnesses, regularly completed dietary surveys every four years for a span of up to 34 years.
It revealed a notable 30% decrease in the risk of premature mortality among the top 10% of participants who adhered most closely to the PHD, in comparison to the lowest 10%. This decrease in risk extended across significant causes of mortality such as cancer, heart disease, and lung disease.
The environmental benefits were equally significant. Those with high adherence to the PHD had a 29% reduction in greenhouse gas emissions, a 21% decrease in fertilizer needs, and a 51% reduction in cropland use. This is important for facilitating reforestation, which helps reduce greenhouse gases driving climate change.
Dietary choices and environmental impact
Walter Willett, the study’s corresponding author, emphasized the critical role of dietary choices in addressing climate change. He noted that the U.S. Department of Agriculture does not consider the environmental impacts of dietary choices in its guidelines. Willett stated, „Our study shows how closely linked human and planetary health are. Eating healthfully boosts environmental sustainability—which in turn is essential for the health and well-being of every person on earth.“
The study underscores the dual benefits of the PHD for personal health and environmental sustainability. By reducing reliance on animal-based foods, the PHD helps mitigate environmental degradation while promoting better health outcomes.
In related news, another Harvard study suggests that daily consumption of olive oil may help prevent dementia and cognitive decline. Additionally, research published in JAMA Network Open indicates that women following the Mediterranean diet experienced a 23% decrease in overall mortality risk.
Harvard scientists have also partnered with Google’s DeepMind AI lab to create a sophisticated virtual rat model. This innovative simulation accurately mirrors natural rat movements and provides an unprecedented tool for exploring complex brain functions.
These studies collectively highlight Harvard’s commitment to advancing health and environmental sustainability through rigorous scientific research.