Fad diets like keto and paleo have a number of experts emphasizing the benefits of each. However, when it comes to its effects on our health and the health of our planet, not all diets are created equal.
Scientists at Tulane University, who examined the nutritional quality and environmental impacts of popular diets in the United States, based on a survey of 16,000 adults, found that the ketogenic and paleolithic diets are the worst based on their carbon footprint and value general nutrition.
Nutritional quality of fad diets
In terms of nutritional quality, the pescatarian diet scored the highest, followed by the vegetarian and vegan diets. The omnivore diet, which was the most common among respondents, fell between the two ends of the spectrum in terms of nutritional quality and climate impact.
Impact on the environment of keto and paleo diets
“It is estimated that the ketogenic diet, which prioritizes large amounts of fat and low amounts of carbohydrates, generates almost 3 kg of carbon dioxide for every 1000 calories consumed”, explain the scientists in a statement about their findings .
“The paleo diet, which replaces grains and beans in favor of meats, nuts and vegetables, received the second lowest score for diet quality and also had a high carbon footprint, with 2.6 kg of carbon dioxide per 1,000 calories.”, they point out.
The Vegan Diet Versus the Keto and Paleo Diets
While a vegan diet has the least impact on the climate, generating 0.7kg of carbon dioxide for every 1,000 calories consumed, less than a quarter of the emissions generated by a ketogenic diet. Vegetarian and pescatarian diets follow. These findings are in line with the results of previous investigations.
“We suspect negative climate impacts because they are meat-centric, but no one has really compared all these diets, as they are chosen by individuals, rather than prescribed by experts, against each other using a common framework.says Professor Diego Rose, director of the nutrition program at the university’s School of Public Health and Tropical Medicine, who led the investigation.
Reduce CO2 emissions by changing your diet
If one-third of all people following an omnivorous diet switched to a vegetarian diet on any given day, it would be equivalent to reducing emissions from about 340 million miles driven by passenger vehicles, according to Rose and her colleagues.
Such reductions would be of considerable significance over time, given that one-third of greenhouse gas emissions are generated by the global food system. Beef production is especially carbon intensive, while also driving deforestation in places like the Amazon.
Similarly, when people on omnivorous diets switched to a more plant-based Mediterranean diet or a DASH diet (the latter is low in fatty meat and recommended for people with hypertension), both the carbon footprint and the food quality scores nutrition have improved, experts say.
Food and carbon footprint
“Climate change is arguably one of the most pressing issues of our time, and many people are interested in switching to a plant-based diet.says Rose.
“Based on our results, this would reduce your footprint and be healthy overall. Our research also shows that there is a way to improve your health and footprint without giving up meat entirely.”, emphasizes.