New findings are the first to calculate the level of food that goes uneaten in individual households. This waste has a clear economic impact, as well as effects on our health and the environment.
For several years, researchers have had a rough idea of how much food is wasted in the United States.
As the team behind the present investigation note, earlier studies have found that 30–40% of the U.S. food supply goes uneaten, leading to a loss of more than $160 billion.
But researchers have struggled to estimate food waste from individual households, due to a lack of wide-ranging, up-to-date data. New research, however, appears to have found the answer.
Professor Edward Jaenicke and doctoral candidate Yang Yu — from the Department of Agricultural Economics, Sociology, and Education at Pennsylvania State University — used a method of production economics to find that U.S. households are wasting nearly one-third of the food that they buy.
As well as costing the economy $240 billion each year, this waste is hitting individual households with a $1,866 annual cost.
In addition, the current level of waste has implications for our health, food production, and the environment.
Prof. Jaenicke and Yu report their findings in the American Journal of Agricultural Economics.
The study’s data were obtained from 4,000 households that took part in the U.S. Department of Agriculture’s National Household Food Acquisition and Purchase Survey (FoodAPS).
Each individual’s height, weight, age, and gender were used to determine the metabolic energy requirements needed to sustain their body weight.
In their investigation, Prof. Jaenicke and Yu employed a method of production economics that reflects the efficiency of a production process using input and output.
The survey data relating to food acquisition became the “input” and the energy required to maintain body weight became the “output.”
Figuring out the amount of food left uneaten was simply a matter of calculating the difference between purchased food and the amount needed to sustain body weight.
The two researchers found that the average U.S. household wastes 31.9% of the food that its members obtain.
Thanks to the amount of data available, Prof. Jaenicke and Yu were also able to determine differences in waste among households of various demographics.
In households that produced more food waste, members tended to have more healthful diets and a higher income.
“It’s possible that programs encouraging healthy diets may unintentionally lead to more waste,” Prof. Jaenicke explains, due to the perishable nature of fruits and vegetables.
The researchers observed lower levels of waste in households with higher levels of food insecurity, households situated farther from their main grocery store, and households in which members drew up shopping lists.
Households with more members also demonstrated less waste. Prof. Jaenicke believes that there is a simple explanation for this.
“People in larger households have more meal management options,” he says. “More people means leftover food is more likely to be eaten.”
Food and portion size may also play a role. “A household of two may not eat an entire head of cauliflower, so some could be wasted, whereas a larger household is more likely to eat all of it, perhaps at a single meal,” notes Prof. Jaenicke.
The findings could encourage less wasteful policies — especially if healthy eating initiatives are indeed leading to more uneaten food.
Prof. Jaenicke says that policymakers should consider how to “fine-tune these programs to reduce potential waste.”
Another important concern involves the effects of food waste on the climate. As Prof. Jaenicke emphasizes, it’s not just food that goes to waste.
“Resources used to produce the uneaten food, including land, energy, water, and labor, are wasted as well.”
“According to the [Food and Agriculture Organization of the United Nations], food waste is responsible for about 3.3 gigatons of greenhouse gas annually,” he continues, “which would be, if regarded as a country, the third-largest emitter of carbon after the U.S. and China.”
Now that researchers know roughly how much food the average household wastes, they can begin to dig deeper into the reasons and provide solutions that will not only benefit individual households, but the planet as a whole.
“We hope our methodology provides a new lens through which to analyze individual household food waste,” Prof. Jaenicke concludes.