Greenhouse gas emissions linked to national dietary guidelines: Study

A new study that looked at the carbon footprints of seven countries revealed that greenhouse gas emissions are associated with national dietary guidelines.

The study, published in the Nutrition Journal, suggested that these guidelines vary significantly between countries, with the United States having the largest carbon footprint while India has the smallest.

These variations are based on the differences in recommendations for and consumptions of individual foods within the six main food groups - protein foods, dairy, grains, fruits, vegetables, and oils/fats.

The corresponding author Diego Rose said in a statement: "Many countries provide recommendations about foods that people should eat for a healthy diet and previous simulations have shown that if the public were to eat according to their government's recommendations, their diets would be both healthier and have a lower carbon footprint."

Rose added: "However, for the US the opposite has been shown; greenhouse gas emissions were simulated to go up if people followed dietary guidelines. This anomaly prompted us to investigate how dietary guidelines vary between countries and the consequent implications for greenhouse gas emissions."

For the study, a team of researchers at Tulane University compared the dietary guidelines and food consumption patterns of seven countries. These include Germany, India, the Netherlands, Oman, Thailand, Uruguay, and the United States.

Findings

The findings suggested that the carbon footprint of India's dietary guidelines was comparatively low, with the recommended diet associated with the equivalent of 0.86 kg CO2 per day, compared to the US' with 3.83 kg CO2 per day.

The carbon footprint of the US dietary guidelines was found to be about 1.2 times that of the Netherlands and about 1.5 times that of Germany.

The US vegetarian dietary guideline, while much lower than the main US guideline in terms of greenhouse gas emissions was still over twice that of India’s.

The greenhouse gas emissions associated with dairy food recommendations were equivalent to 0.17 and 1.10 kg CO2 per day, respectively.

The greenhouse gas emissions associated with the protein food recommendations ranged from 0.03 kg CO2 per day in India to 1.84 kg CO2 in the US, for recommended amounts of 75g per day and 156g per day, respectively.

Limitation

The limitation of the study is that it only considered a single environmental impact of diets, greenhouse gas emissions. Other environmental impacts, such as land and water use, should be considered when evaluating the overall impact of a diet, the authors mentioned