A new study has revealed that following a diet based on fruits, vegetables and whole grains can have positive impact on human health and help save the planet.
According to the study, published Monday in The American Journal of Clinical Nutrition, this planet-friendly diet reduces the risk of early death by nearly one-third, while reducing greenhouse gas emissions.
Double Benefit
Commenting on the study results, Dr. David Katz, a specialist in preventive and lifestyle medicine, told CNN: “Eating more whole plant foods, less animal foods, and less highly processed foods is better for people and planet alike.”
Katz, who was not involved in the study, added: “In this paper, we see that same message amplified: adhering to a dietary pattern conducive to the health of the planet and sustainability is associated with meaningful reductions in all-cause mortality.”
Food and Climate Change
Food production is related to the climate crisis, according to experts. For example, raising livestock for human consumption uses large swathes of agricultural land. Moreover, it plays a role in deforestation, biodiversity loss, and water pollution.
Animals produce harmful gases, including methane, accounting for 32% of human-caused methane emissions. Methane is a greenhouse gas that can cause 1 million premature death every year. It is also 80 times more powerful than carbon dioxide in warming the planet, according to the UN Environment Program.
Experts point out that one adult cow can emit up to 500 liters of methane a day. Hence, livestock can generate around 15% of global greenhouse gas emissions.
Planet-friendly Diet
On the other hand, adopting a planet-friendly diet can reduce cropland use by 51%, lower greenhouse gas emissions by 29%, and cut fertilizer use by 21%. Furthermore, it prolongs the lives of humans, as the study revealed.
In this regard, the study’s corresponding author Walter Willett said: “Changing how we eat can help slow climate change, and fortunately what’s healthiest for the planet is also best for us.”
Willet, who is a professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health in Boston, added: “For every major cause of death we looked at, there was a lower risk in people with better adherence to the planetary health diet.”
Dietary Guidelines
The study relied on the analysis of dietary data from more than 200,000 individuals to see how it compared with the Eat-Lancet dietary guidelines, which focus on higher consumption of fruits and vegetables, whole grains, legumes and other plant-based proteins while reducing meat and dairy to small portions.
Over 34 years, study participants filled dietary questionnaires every four years. After that, researchers scored the diets based on the intake of 15 food groups.
Planet-friendly foods, including whole grains, tubers, vegetables, whole fruits, legumes, soybean foods and unsaturated plant oils, such as olive oil, consume fewer resources to grow. The study also measured foods that use large amount of land, including cattle, and to a lesser extent sheep, goats, and poultry, as well as intake of added sugar.
The scope of this study was larger than previous studies that examined the impact of the planetary health diet. In this respect, Willet said: “This is a substantially larger and much longer study which has repeated assessments of diet over more than three decades, which allows more statistical precision.”
Study Results
According to the study, the top 10% of people who followed the Eat-Lancet dietary guidelines were 30% less likely to experience premature death from any cause than those in the bottom 10%.
Moreover, individuals who strictly followed the planetary health diet 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 a respiratory disease, Willet said.
“The findings show just how 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,” he added.
