A new study has found that unhealthy food and drink options such as store-bought cake, sweet treats and alcohol account for nearly a quarter of diet-related greenhouse gas emissions.
A team from the University of Leeds looked at the effect of poor diet, beyond simply the impact on the individual's health. The research, which analysed at more than 40,000 branded items and 3000 generic food products, found that by choosing unhealthy options, you also increase your carbon footprint.
The study's lead author, Dr Holly Rippin, a post-doctoral researcher based at the university's School of Medicine, said "big cultural changes" are required to combat the climate crisis.
"We all want to do our bit to help save the planet and the decisions we make can contribute to that cause," she said.
"It's true that we do need big cultural changes – such as significantly reducing our consumption of meat and dairy products which together contribute around 46 per cent of our diet-related emissions.
"However, our work shows that small changes can also produce big gains. You can live a more environmentally sustainable life by just cutting out sweets and drinking less coffee."
The study looked at the greenhouse gas emissions linked to production and transport of certain foods and then cross referenced it with the nutrient value of those foods, based on World Health Organisation guidelines.
The findings showed that sweets, cakes and biscuits were responsible for around 8.5 per cent of food-related greenhouse gases, while beverages such as tea, coffee and alcohol added another 15.1 per cent.
The study, published in scientific journal PLOS One, also analysed the food consumption of 212 adults over three separate 24-hour periods.
Diets that included meat were found to produce 59 per cent more greenhouse gas emissions than vegetarian diets, and men's diets were shown to contribute 41 per cent more greenhouse gases than women.
"Other studies have suggested that men's higher diet-related emissions reflected their need for more energy," said Darren Greenwood, a senior lecturer in biostatistics at Leeds University. "Unfortunately, it appears that they look to get those calories from meat rather than lower impact foods."
Professor Janet Cade from the University's School of Food Science and Nutrition, agreed with the findings, stating: "This detailed study confirms that diets that are better for the planet's health are better for our own personal health too.
"It also raises more issues around the labelling of food as different brands of the same product vary in their environmental impact."