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Planetary Health Diet focuses on human/planet sustainability

People who eat minimally processed foods may be at lower risk of premature death, study finds
HEALTH STUDY: Harvard T.H. Chan School of Public Health have announced findings of a large study evaluating the impact of eating what scientists call a Planetary Health Diet.

A study led by the Harvard T.H. Chan School of Public Health published on June 10, 2024, in The American Journal of Clinical Nutrition may prove author Michael Pollan right, when he said, "eat food, mostly plants," in his book, In Defense of Food

The study concluded that people who eat a mostly plant-based, sustainable diet may substantially lower their risk of premature death in addition to their environmental impact. 

A media release from the school stated that researchers have named the dietary pattern outlined in the report, which "emphasizes a variety of minimally processed plant foods but allows for modest consumption of meat and dairy foods,” the Planetary Health Diet (PHD).

According to the release, it is the first large study to directly evaluate the impacts of adherence to recommendations in the landmark 2019 EAT-Lancet report, which found that a diet rich in plant-based foods, with fewer animal-sourced foods, confers both improved health and environmental benefits.

Climate change has our planet on track for ecological disaster, and our food system plays a major role,” stated corresponding author Walter Willett, professor of epidemiology and nutrition. “Shifting how we eat can help slow the process of climate change. And what’s healthiest for the planet is also healthiest for humans.”

There have been many studies looking at the planetary and human health impacts of diets that emphasize putting a majority of leafy greens, seeds, nuts, grains and legumes on one's plate, but the studies have not been long term.

According to the release, researchers used health data from more than 200,000 women and men who were free of major chronic diseases at the start of the study and completed dietary questionnaires every four years for up to 34 years. 

Researchers scored participants' diets based on intake of 15 food groups, including whole grainsvegetables, poultry and nuts.

The study found that the risk of premature death was 30 per cent lower in participants most closely adhering to PHD. Every major cause of death, including cancerheart disease and lung disease, was lower with greater adherence to this dietary pattern, the release stated.

Researchers noted that land use reduction is particularly important as a facilitator of reforestation, which is seen as an effective way to further reduce levels of greenhouse gases that are driving climate change.

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