Food waste (FW) as a topic had touched our lives long before we met. While Monika was personally shocked and surprised to see people waste food in US (having moved for school) and impressed by Dr. Jonathan Foley’s idea of waste reduction as solution to meeting food demands for growing population; Martine had already taken a step further by writing a theory paper looking at FW in an economic framework. Not surprisingly she followed with some quantitative work for the European Commission, FAO and African Journal of Agricultural and Resource Economics followed suit. However something was missing. All the works thus far used FAO food waste and lost percentages as given and fixed. This didn’t feel right and lead to a general uneasiness regarding the approach and reaching out to Prof. Thomas Hertel (figure below) dealing with a similar questions.
Together Martine and Monika decided to explore it and were able to rope in Thom to join to band. The big question was how does consumer FW respond to the affluence of consumers? Enter the data challenges - while data on monetary measures is relatively abundant, the same can’t be said about that on FW! The more we read on FW the more we realized there was no single consistent definition of FW and while some countries had some limited data, nothing ensured that comparing FW across any two countries was comparing apples to apples. FAO being the most cited source on FW, we turned attention to this source but the more we dug into the details underlying the FAO FW numbers, the less we were convinced that it would serve the purpose.
The prime hurdle therefore became definitional in nature - what definition of FW to use? The answer (figure below) came from most unusual of the places – a café. While waiting for lunch, Monika noticed people being served a plate of food, most ate a portion of the food on their plate, but what was left was not used for human consumption. This became our definition – food meant/available for human consumption but not eaten!
While we got financial support and our intern Linda for this work (thanks to Thom), we were not funded well enough to launch surveys visiting cafes across the globe! So how do we measure FW for many countries? The answer came from a study done for US – measure FW as difference between food available to eat and food consumed, where consumption was measured as food needed to maintain Basal metabolic rate, physical activity lifestyle and gains in weight overtime. This was brilliant! We started looking for a consistent source of bodyweight data, and along came World Health Survey from World Health Organization. FAO data on Food Balance Sheets was taken as a measure of food availability and the difference was FW.
Things started to fall in place bit by bit. Data available for a set of 63 countries showed a very clear relationship (figure below) between FW thus obtained and actual individual consumption (AIC) expenditure (from World Bank International Comparisons Project data).
This relationship told us that globally consumers were wasting almost 19% of calories available instead of 8% estimated using FAO’s fixed fraction approach! Not only that, it told us how soon consumers started to throw food away when they become richer. All combined together, these were results worth sharing and had implications not just for policy but also theory. PLoS ONE saw this potential. The attention that followed from international and national media (one example) gives testimony to the general interest in the subject. We also hope that popular reporting and debate on these findings get people’s attention to act towards reducing food waste in homes, canteens and other eating places; and for institutions to think about setting incentives throughout supply-chain stages that help achieve these objectives.