A large study of almost 35,000 people reports that environmental sustainability could be greatly enriched if we all began taking on more plant-based organic, healthier diets.
Many organizations, including the UN's Food and Agriculture Organization, advocate the urgent adoption of more sustainable diets at a global level. Such diets include reduced consumption of animal products, which have a higher environmental impact than plant-based products. This is mainly due to the high energy requirements of livestock farming as well as the very large contribution of livestock to greenhouse gas emissions. Intensive livestock production is also responsible for significant biodiversity loss due to conversion of natural habitats to grass and feed crops.
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To do this, researchers obtained information on food intake and organic food consumption from more than 34,000 French adults. They used what's called a 'provegetarian' score to determine preferences for plant-based or animal-based food products. The researchers also conducted production life cycle environmental impact assessments at the farm level against three environmental indicators: greenhouse gas emissions, cumulative energy demand and land occupation.
The good news is that this kind of dietary change is something that would benefit each and every one of us. The bad news is that this study doesn’t take into account the fact that we may have crossed the rubicon.
"We didn't look at other indicators such as pesticide use, leaching and soil quality which are relevant to the environmental impacts of productions systems," says Louise Seconda. "Therefore future studies could also consider these as well as supply chain and distribution impacts of food production."
All of this being said, your grandmother was right, you should be eating more greens and vegetables.