Climate change and diet – Why Should our Dietary Habits Matter?

Climate change has been recognised as the biggest global health threat of the 21st century. Several health consequences of a changing climate have been identified with a high degree of certainty and will increase if no action is taken. Therefore, the need for action has never been clearer. Reducing greenhouse gas emissions (GHGEs) and transitioning to a low-carbon economy will require a global effort. It is not only how we choose to travel or heat our homes that have an impact on our carbon footprint. Indeed, the food system has also a strong effect on the environment and is becoming a major issue for policy makers. But why should what we eat matter and contribute to the increase of GHGEs?


What we eat affects not only our health, but also air, water, soil and overall the climate. During the life-cycle of food, numerous human-induced activities cause GHGEs from the farming process itself to manufacture, distribution and cold storage through to food preparation and consumption in the home and the disposal of waste. Every single step of production and distribution produces GHGEs and thus harm the environment. A report of the Food and Agriculture Organisation (FAO) of the United Nations has shown that accounting for all factors, livestock production causes 18% of the world’s global GHGEs. This represents more than the emissions of all the world’s cars, buses, planes, and trains combined. A recent study has shown that if the current trends continue, food production alone will reach, if not exceed, the global targets for total GHGEs in 2050.


In terms of food choices, animal-derived foods, such as meat, butter and eggs have a higher environmental impact, as the same amount of plant foods, such as fruits, vegetables and bread. Especially the meat production is harmful to the environment: the average production of 1 kg of industrial produced beef can be just as damaging to the climate as driving 250 kilometres. In addition, the global population is growing whereas the standard of living of countries such as China or India is also improving. Therefore, the food demand is constantly increasing which will also raise fuel expenditures to operate tractors, seagoing trawlers, refrigerators, fertilizer production, transportation and industrial food processing plants.   Moreover, researchers have found that plant-based diets reduced GHGEs that could decrease the impact climate change has also on the food production. For example, a recently published study in the UK has shown that a reduction of GHGEs of around 40% can be achieved by making realistic dietary changes towards a consumption of fewer animal products and processed snacks and more fruit, vegetables and cereals. Changing towards a more sustainable diet has also positive effects for our health. It has been shown that for example vegetarian, Mediterranean and pescatarian diets reduce substantially the risk of diseases such as type 2 diabetes, cancer and cardio-vascular diseases.


Diet is an important factor and determinant of health. Especially the industrialised countries are currently facing an epidemic as more and more people are becoming obese. The Organisation for Economic Organisation and Development (OECD) showed in the Obesity Report 2014 that 15% and 20% of children in France and Germany (30% in the USA) are overweight including obese underlining a rising trend.   Obesity is a risk factor for some of the leading causes of preventable death such as heart disease, stroke, type 2 diabetes, and certain types of cancer. Therefore, it represents a major health challenge and also an economic concern. On the other hand, low and middle-income countries are often facing a double burden of malnutrition meaning under- and overnutrition occurring simultaneously among different population groups. With the rapid increase in economic development, globalization, and urbanization, most of these countries may also be in the midst of a “nutritional transition” with major modifications in the food choices and eating habits that progressively become more westernised.


Good nutrition is an important protective factor against obesity and other related diseases. The difficult issue of diets are that our choices are influenced by many factors: culture, nutritional knowledge, price, availability, taste and convenience. In addition, most of the current dietary guidelines do not take into account the environmental impact. In a world with a growing population and increasing GHGEs, should we not consider the footprint of dietary guidelines to promote sustainable and healthy diets at the same time?

In France, a National Programme on Nutrition and Health (PNNS) has been established that is also charge for developing dietary guidelines. This programme is coordinated by the National Institute for Prevention and Health Education (INPES) and regroups several experts from different institutions. Different types of guidelines have been developed for a variety of public (for young and old people, pregnant women, etc.). Nevertheless, none of the guidelines took into consideration the environmental aspects of diets.

In Germany, the German Nutrition Society (DGE) is responsible for the dietary guidelines that were lastly published in 2013 and endorsed by the Ministries of Health and Agriculture. To date, the German dietary guidelines do not consider the footprint of diets. However, in a current press release, the German Nutrition Society welcomes officially the initiative to reduce meat consumption to promote health and environmental sustainability.

In the United States (US), the recently published dietary guidelines for Americans 2015 reflect both the healthy as well as the environmental potential benefits. Usually, the committee that was formed in 1983, takes only nutrition into account but this year, for the first time, they also considered the environmental impact by discussing the idea of environmental sustainability of diets. They suggested that Americans should consume a more plant-based diet and less animal-based foods. It is a first step in the right direction by promoting health and lesser environmental impact than the current average US diet.

Moreover, the Brazilian dietary guidelines, also recently published, have received much attention as they present an excellent example of promoting healthy and sustainable diets. They recommend briefly in around 80 pages to eat “minimally processed foods, mainly of plant origin, which are the basis for diets that are nutritious, delicious, appropriate, and supportive of socially and environmentally sustainable food systems”. In addition to the sustainable approach, the unique aspect of these guidelines is that they considered the social, cultural, economic and environmental aspects of meals and foods.

Overall, a shift to healthier and sustainable diets that are affordable to all social groups is just one of a number of actions that need to be taken in the fight against climate change. Improving our own health and the health of the planet can be a good argument and motivation for changing our dietary habits as we have the potential to make a significant difference.

Stefanie Schütte

Licence Creative Commons