Adopting a planet-friendly diet rich in fruits, vegetables, and whole grains can significantly reduce the risk of premature death, while also helping to combat climate change, according to a new study. The research found that individuals who closely follow this diet can lower their risk of early death by nearly one-third. In addition to the health benefits, this diet also dramatically reduces the release of greenhouse gases that are contributing to environmental degradation.
“Eating more whole plant foods, less animal foods, and less highly processed foods is better for people and the planet alike,” said Dr. David Katz, a specialist in preventive and lifestyle medicine who was not involved in the study. Dr. Katz, founder of the nonprofit True Health Initiative, emphasized that adhering to a dietary pattern that supports planetary health is also associated with meaningful reductions in all-cause mortality.
The Environmental Impact of Food Production
Food production plays a significant role in the climate crisis. The process of raising livestock for human consumption requires vast amounts of agricultural land and contributes to deforestation, biodiversity loss, and water pollution. Ruminant animals such as cattle, sheep, and goats are particularly problematic, as they emit large quantities of methane—a greenhouse gas that is 80 times more potent than carbon dioxide in terms of warming the planet over a 20-year period.
According to the United Nations Environment Programme, a single adult cow can emit up to 500 liters of methane per day through belching and flatulence. When combined, these emissions contribute to nearly 15% of total global greenhouse gas emissions.
However, the study found that following a planet-healthy diet can significantly reduce the environmental impact of food production. The research showed that such a diet could cut land use by 51%, greenhouse gas emissions by 29%, and fertilizer use by 21%, while also extending the lives of those who adhere to it.
A Diet That Benefits Both People and the Planet
Walter Willett, the corresponding author of the study and a professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health, highlighted the dual benefits of a planet-first diet: “Changing how we eat can help slow climate change, and fortunately, what’s healthiest for the planet is also best for us.”
The study, published in The American Journal of Clinical Nutrition analyzed data from over 200,000 men and women who participated in long-term government studies such as the Nurses’ Health Study I and II, and the Health Professionals Follow-Up Study. Participants provided dietary information every four years for 34 years, allowing researchers to gather a substantial amount of data.
The researchers then scored the participants’ diets based on the intake of 15 food groups, focusing on foods that are environmentally friendly, such as whole grains, tubers, vegetables, whole fruits, legumes, soy-based foods, and unsaturated plant oils. Conversely, foods that require large amounts of land, such as cattle and other livestock, were also measured, along with added sugars, which are known to have several health risks.
Significant Findings and Health Benefits
The study found that individuals in the top 10% of adherence to the Eat-Lancet planetary diet were 30% less likely to die prematurely from any cause compared to those in the bottom 10%. Additionally, the most adherent participants had a 28% lower risk of neurodegenerative mortality, a 14% lower risk of dying from cardiovascular disease, a 10% lower risk of dying from cancer, and a 47% lower risk of dying from respiratory diseases, even among non-smokers.
“These findings show just how linked human and planetary health are,” Willett said. “Eating healthfully boosts environmental sustainability — which in turn is essential for the health and well-being of every person on Earth.”
The results of this study underscore the importance of dietary choices not only for personal health but also for the health of the planet. By adopting a planet-first diet, individuals can reduce their risk of early death while also playing a critical role in mitigating the effects of climate change. This dual benefit makes the planet-friendly diet a powerful tool for promoting both human health and environmental sustainability.
