How much food are we really throwing out?

By Birgitte Dalgaard, bird@tek.sdu.dk

- We don't know nearly enough about how much food we are throwing out and which initiatives are helping to reduce food waste, says Associate Professor Gang Liu from the SDU Centre for Life Cycle Engineering.

Along with colleagues from universities in Europe, the USA, and China, Gang Liu has examined all available food waste data in the literature between 1933 and 2015 for 84 countries. The results have been assembled in the report Missing Food, Missing Data? A Critical Review of Global Food Losses and Food Waste Data, which has been recently published in the prestigious journal Environmental Science and Technology.

Missing Food, Missing Data? A Critical Review of Global Food Losses and Food Waste Data

- We discovered that data collection is focused on a handful of countries, especially the USA, UK, and Nordic countries. Many research articles use old figures, and more than half of the articles are based exclusively on secondary sources. This signals a high degree of uncertainty in the existing global database on food waste, underlines Gang Liu.

Lack of knowledge in Denmark

Also in Denmark, we do not quite know how much food we actually throw into the trash bin. In his work looking through the data from around the world, Gang Liu came across a Danish report from the Copenhagen Resource Institute, which shows that existing Danish data on food waste are between 15-25 years old, while food waste data for the various stages of the supply chain, especially in wholesalers, are even older and rarer.

This lack of basic data and knowledge about food waste is an obstacle when we need to find the most effective strategies for reducing food waste. Taking consumer waste as an example, it is in people's homes where the most food is thrown out; however, most of the stop food waste initiatives are targeted at food waste in shops or restaurants.

Knowledge needed to achieve UN Goal

Food waste is a subject that attracts growing political and popular attention. The UN estimates that a third of our food, or around 1.3 billion tons per year is wasted from farm to table.

And this has a considerable impact on the environment. Food waste represents 8% of global CO2 emissions and costs a total of 750 million USD - same as the GDP of Turkey. In addition, the moral argument can be made that it is reprehensible to throw out so much food when so many people on the planet are starving.

In 2015, 193 world leaders agreed to 17 Global Goals for Sustainable Development. One of the Goals is to reduce food waste by half by 2030. In March, the Danish government followed this up with the "Action Plan for the UN's Global Goals".

UN target 12.3: By 2030, halve per capita global food waste at the retail and consumer levels and reduce food losses along production and supply chains, including post-harvest losses

- It's difficult for individual countries to set a concrete target for food waste when they don't know what the starting point is. Also, in order to counteract food waste you need to know what works the best. In Denmark, initiatives like Stop Madspild, Wefood and Too Good To Go are popping up, but to what extent are they actually working? asks Gang Liu and continues:

- When you consider the scale and trend of food waste today, there is no doubt that action has to be taken quickly. In the report, we recommend that on a national level we need to have more updated knowledge about how much food is being thrown out, set a concrete target based on that and find out where in the food supply chain to put which initiatives.