There is increasing interest in growing and eating foods with a lower carbon footprint as climate change effects become more widely known. Currently, the food system is a substantial contributor to environmental problems. Changing these food systems in the future could positively impact both population health and environmental sustainability, with dietary choices playing an important role. However, there is little information on the carbon footprint of actual American diets and how they relate to diet quality.
A new research paper looks at several popular diets and what it costs the environment to follow any of them, contrasting with their real-life benefits regarding diet quality.
Study: Popular diets as selected by adults in the United States show wide variation in carbon footprints and diet quality. Image Credit: alphaspirit.it / Shutterstock
Introduction
Modern agriculture significantly contributes to the unstable health and sustainability scenario brought about by climate change. Consumer demand could drive future trends in food production. An earlier study showed that about one in seven people in the USA would change their dietary patterns to promote environmental sustainability.
This begs the question, which diet pattern is the most sustainable as well as healthy? The current study, published in the American Journal of Clinical Nutrition, attempts to classify six diets – vegan, vegetarian, pescatarian, paleo, keto, and others – by these parameters.
The data came from the NHANES (2005-2010) study that analyzed individual 24-h dietary recall data in a nationally representative survey measuring the health and nutritional status of the US population. First, the scientists calculated the carbon footprint – the greenhouse gas emissions (GHGEs) – as kg of carbon dioxide equivalents (kg CO2-eq), per 1000 kcal. To assess diet quality, they also looked at two scores, the Healthy Eating Index (HEI) and the Alternate Healthy Eating Index (AHEI).
Earlier research has shown that plant-based diets are the greenest. Similarly, replacing some meat with plant foods may reduce the GHGEs. In this study, the United States Department of…