Greenhouse gas emissions associated with national dietary guidelines vary widely between countries, with US guidelines having the largest carbon footprint and India’s the smallest, according to a study involving seven countries published in open access. Journal of Nutrition. These variations are due to differences in recommendations and intakes for individual foods within the six major food groups—protein foods, dairy foods, grains, fruits, vegetables, and oils/fats.
Diego Rose, corresponding author, said: “Many countries provide recommendations about what foods to eat for a healthy diet, and previous simulations show that if the public eats according to their government’s recommendations, their diets will be both healthier and have a lower carbon footprint. But , showed the opposite in the United States; greenhouse gas emissions were simulated to increase, if people followed dietary guidelines. This discrepancy prompted us to investigate how dietary guidelines vary between countries and the implications for greenhouse gas emissions.”
To investigate the differences in greenhouse gas emissions associated with different dietary guidelines, a team of Tulane University researchers compared the dietary guidelines and food intake patterns of seven countries: Germany, India, the Netherlands, Oman, Thailand, Uruguay, and the United States.
The authors found that the carbon footprint of India’s dietary guidelines was relatively low, with 0.86 kg of CO equivalent associated with the recommended diet.2 per day, 3.83 kg CO compared to the US2 Every day. The carbon footprint of US dietary guidelines was found to be about 1.2 times that of the Netherlands (2.86 kg CO equivalent).2 per day) and about 1.5 times that of Germany (equivalent to 2.25 kg of CO2 daily). The US Vegetarian Dietary Guidelines, however, are much lower than the main US guidelines in terms of greenhouse gas emissions (1.80 kg CO equivalent).2 per day), was still twice as high as in India due to high US dairy recommendations.
The authors also found that the main difference between the dietary guidelines of different countries is the wide range of daily recommended amounts for each food group, especially protein and dairy. Daily recommended amounts of dairy products range from 118ml per day for Oman to 710ml per day for the US. The greenhouse gas emissions associated with these two recommendations were 0.17 and 1.10 kg CO equivalents.2 daily, respectively. Greenhouse gas emissions associated with protein food recommendations are 0.03 kg CO2 1.84 kg CO per day in India2 In the United States, the recommended amounts are 75 grams per day and 156 grams per day, respectively.
The guidelines also varied in terms of which foods were included in each food group. Protein food recommendations in Germany and Uruguay included only animal protein, the United States and Thailand recommended a full spectrum of plant and animal protein foods, while India recommended only plant protein. The US Vegetarian Guidelines recommend plant proteins, as well as dairy and eggs.
Brittany Kovacs, lead author, said: “Because there is wide variation in the global warming impact of these individual foods, what foods people eat and how much of them affect the carbon footprint of the Dietary Guidelines. For example, beef consumption in Uruguay, mutton and lamb protein foods 31 %, whereas in Germany it is only 16%. Thus, our calculated greenhouse gas emissions for protein food recommendations in Uruguay are 53% higher than in Germany, even though the volume recommendations for protein foods as a food group in both countries are almost the same.”
Diego Rose added: “The US vegetarian guidelines are almost identical to the recommendations of the main US guidelines except for the protein group — which recommends legumes, soy, nuts and seeds as well as eggs — resulting in an overall carbon footprint that is less than half that.”
The authors caution that the study only considered the single environmental impact of food, greenhouse gas emissions. Other environmental impacts, such as land and water use, should be considered when assessing the overall impact of food. The study is limited to the daily quantitative recommendations of the dietary guidelines of seven countries, which may limit its generalizability to other countries.
Brittany Kovacs said: “These findings hold insights for the future development of dietary guidelines and highlight the importance of incorporating sustainability considerations such as reducing protein food and dairy recommendations and/or including more plant-based alternatives to animal-based products. More sustainable, yet healthier. -based, by incorporating considerations into dietary recommendations, it is possible to influence the environmental impacts of the larger food and agriculture sectors in different countries and globally.