Research keeps telling us that what we eat has a big impact on the planet. In fact, a 2021 United Nations-backed study found that 34% of greenhouse gas emissions come from the food system. Given the urgency with which we need to address this warming world of ours, food choices can play a starring role for anyone who wants to participate less in contributing to climate change.
Food choices are also tricky. With many factors to consider—from ethics and access to nutrition and the latest fads—many of us cycle from one diet style to the next. But if your priorities are carbon footprint and/or nutritional value, then recent research from Tulane University may be of interest.
The study compared six popular diets on both nutritional quality and environmental impact. The researchers compiled diet quality scores using data from more than 16,000 adult diets in the United States collected by the CDC’s National Health and Nutrition Examination Survey and looked at vegan, vegetarian, pescatarian, paleo, and keto-style diets, with everything else being categorized as omnivore.
Keto and Paleo Tank for Eco Impact and Nutrition
Many of us know that red meat has a high carbon footprint—remember how Democrats want to take away everyone’s hamburgers because of climate change? (They don’t. Kind of.) So it may not be too surprising that the meat-forward keto and paleo diets ranked as the least sustainable of the six diets examined. And also probably not surprising that those diets scored the lowest for nutritional value as well.
As Tulane’s Andrew J. Yawn explains in a press release about the study:
“The keto diet, which prioritizes high amounts of fat and low amounts of carbs, was estimated to generate almost 3 kg of carbon dioxide for every 1,000 calories consumed. The paleo diet, which eschews grains and beans in favor of meats, nuts, and vegetables, received the next lowest diet quality score and also had a high carbon footprint, at 2.6 kg of carbon dioxide per 1,000 calories.”
Diego Rose, the study’s senior author and professor and nutrition program director at Tulane University School of Public Health and Tropical Medicine, says that…