Eating habits and sociodemographic factors impact household dietary greenhouse gas emissions reduction in Great Britain

Dietary changes can substantially reduce greenhouse gas emissions in Great Britain. Guidelines recommend reducing meat and dairy consumption while increasing plant-based foods, but household purchasing habits achieving these shifts are not well understood. Here we analysed food purchase data from ~30,000 British households (2012–2019), identifying 709 households that reduced their dietary greenhouse gas emissions by 34%. Using latent class analysis, we identified two distinct clusters among these households: plant-based adopters who reduced meat and dairy, adopting healthier diets; and households replacing meat with dairy and convenience foods, showing less healthy dietary changes. Plant-based adopters typically had higher education, higher incomes, were older (45+ years), and smaller in size. Households shifting toward dairy and convenience foods were older and smaller. Supporting healthy and sustainable diets requires targeted policies to enhance affordability, availability, and convenience of nutritious plant-based foods.