Your daily decisions about food have an impact on the environment
Eating is something we do every day, and food is such an everyday topic, of course: we make decisions about these on a daily basis. Perhaps this is why many of us never come to think about the environmental impact of the decisions we make about what we eat. The carbon footprint and other environmental impacts of different foods can be studied using life-cycle analysis. This looks at the complete supply chain from raw material production to the dinner table. It shows that eating contributes more than a third of the total impact of private consumption, trumping both housing and transportation.
Juha-Matti Katajajuuri, senior research scientist, MTT Agrifood Research Finland
Nutritional advice offered in industrialised nations today generally emphasises the idea of a healthy, balanced plateful of vegetable-rich nutrition. Foods based on plant raw materials are, as such, less harmful to the environment than foods based on animal raw materials.
Yet the extent of the difference in impact between a mixed and a vegetarian diet is open to debate, and there is no simple answer: some studies suggest the difference is relatively small, while others claim it is very significant. The variance in outcomes is explained by differences in the calculation methods applied and in the composition of the mixed or vegetarian diets considered. Foods are usually compared by weight to calculate their relative environmental impacts, which only provides part of the picture: nutritional content and volume should also be considered. It is not meaningful to compare a kilo of meat to a kilo of vegetables. Nevertheless, it is clear that seasonal vegetables are the foundation of a climate friendly diet, and as the growing season approaches, you can soon eat anything the fields and forests yield without having to worry too much about the environment.
Discarded food is an environmental burden we can avoid
People often think that transportation and packaging have a major role to play in the total environmental impact of food. Research shows that this is not the case, however. For instance, a study of the production chain for a Finnish chicken product shows that all transportation, including the shipping of soy from Brazil, makes up only four per cent of the lifetime environmental impact of the product studied. Of the four per cent, distribution to shops and stores in Finland accounted for roughly half. In fact, transporting food across oceans in huge ships is extremely efficient per kilo of product.
This means that transportation in itself does not explain the environmental friendliness of local food. Instead, the advantages of local food lie in the support it gives to diverse production and to local economies and employment. We used to talk about how tomatoes are imported by airplane, but the truth is that today air freight is a rare exception and nearly all imported tomatoes come to Finland by land or sea. Often agriculture plays the single most important role in the environmental impact of food, and so the type of food we eat and the conditions and manner in which it is produced are paramount.
In fact, producing food that will be end up discarded is more harmful to the environment than producing packaging. For example, throwing just half a slice of rye bread or a single slice of ham in the bin causes greater harm to the environment than the manufacture and waste management of the packaging. Many are actually surprised that it is impossible to determine the environmental friendliness of packaging based on the material used: the most ecological of all types of packaging are the ones that ensure minimal wastage of food because they help us avoid the preventable environmental impacts of food production.
Juha-Matti Katajajuuri, senior research scientist
MTT Agrifood Research Finland, Biotechnology and Food Research, Sustainable Bioeconomy team
The author is the leading Finnish scholar on calculating the carbon footprint of food and how this can be further developed. He is currently Project Leader in the three-year Foodprint project, which is developing practical and harmonised science-based guidelines for calculating the carbon footprint of foods.