This blog post discusses our team’s recently published peer-reviewed article. For the full article, please visit this page.
As we have discussed in previous blog posts, food waste is now recognized around the world as a pressing environmental, social and economic issue. Although food waste occurs at all stages of food production and consumption, some estimates suggest that up to 50% of food waste in Canada is generated at the household-level. As awareness around food waste grows, pressure is building to develop effective and timely solutions.
However, evidence-based suggestions and high-quality food waste data remain relatively scarce. Without a solid foundation and understanding of food waste, how can we inform narratives that encourage consumer behaviour change? So far, there is little academic literature that systematically observes household food waste generation in a Canadian context.
Our interdisciplinary team from various departments across campus sought to fill this gap by conducting a study among families with young children living in Guelph, ON.
Throughout the study, all families were asked to keep track of every food purchase receipt – from grocery stores and farmers markets to restaurants and take-away establishments – anywhere that food was purchased. Throughout this period, we collected each families’ household waste including their recycling, garbage and organics. This waste was then audited by a team of very dedicated (and brave!) graduate students in the first year, and by a professional audit company the second year. Each individual food item was separated, recorded and weighed. All food items were also classified as being either avoidable or unavoidable. For example, a whole banana would be peeled, and the peel would be considered unavoidable, whereas the actual banana would be avoidable. Our focus was on the avoidable portion of food waste – any food that was at some point edible. In the end, we had 316 unique avoidable food items. It was this list that formed the basis of our subsequent analysis.
What did we find?
Overall, the average household in our study generated approximately 2.98kg of avoidable food waste per week. Fruits and vegetables made up two thirds of this waste, followed by breads and cereal making up about a quarter of total waste.
That being said, it can sometimes be difficult to visualize food waste in terms of a weight value. In order to further contextualize these results, we examined the dollar value, nutritional losses as well as environmental impacts of what was thrown away.
In our study, one week of avoidable household food waste represented…
This is the recommended daily caloric intake for 1.7 children or 2.2 adults. This means that the average household in our study could have provided an additional five adult meals, or 7 child meals based on the edible items they wasted. The items wasted also represented significant losses of fibre, magnesium, calcium, vitamin D, vitamin B12, vitamin C and vitamin A – all nutrients that are often consumed below recommended intake levels in Canada. Weekly wasted food represented 2.3 servings of fibre, 2.5 servings of vitamin D, 1 serving of vitamin B12, 4.8 servings of vitamin C, 1.9 servings of vitamin A, 0.9 servings of calcium and 1.6 servings of magnesium.
In this case, wasted fruits and vegetables represented a significant missed health opportunity.
An extra $18 a week in a family’s pocket could go a long way!
23.3 kg of CO2.
This equates to 1.2 tons of carbon dioxide which is equivalent to one quarter of the emissions from a car being driven for a year, or 2.8 barrels of oil consumed.
6.7 m2 of land and 5000 L of water.
Consider that the average 5-minute shower uses 35 liters of water. Wasted avoidable food items represent close to 143 showers per week!
What does this mean?
These multiple valuation frameworks provide different means of communicating the impacts of food waste to both policy makers and the public at large. Our hope is that these new perspectives, based on detailed observations of family food behaviours rather than estimations derived from system-wide data, will enable more informed and urgent conversations around food waste in Canada.
von Massow, M., Parizeau, K., Gallant, M., Wickson, M., Haines, J., Ma, D. W. L., … Duncan, A. M. (2019). Valuing the Multiple Impacts of Household Food Waste. Frontiers in Nutrition. Retrieved from https://www.frontiersin.org/article/10.3389/fnut.2019.00143