(Warning: This post is a bit lengthy and technical. If you don’t like long reads – and congrats on knowing yourself well! – I still encourage you to learn about food waste in these shorter, well-written media articles, here, here and here.)
Food waste is a massive problem in this country. Enter the search term “food waste in the US”, and you see the stunning statistic mentioned over and over again: 30% – 40% of the food supply in the US is never eaten. This is happening while one in eight Americans struggles to put food on the table (i.e. report being “food insecure at least sometimes”). The less waste we create, the easier it’ll be to feed the world’s hungry without diverting more land and natural resources, all while slashing the tremendous burden food waste has on the environment.
But what does this 40% statistic even mean? How do I contextualize this number, and how much $$ are we talking about? What type of food goes uneaten more often and why? Where do we go wrong in the supply chain? Should we blame consumers for being ignorant and lazy, and can we realistically reach “zero waste”? With these questions in mind, I set out to do a DDD (deep data dive, DUH).
But first, let’s take a selfie – *ahem* excuse me, I meant – first let’s define terminology.
Food waste is difficult to study partly because we are all using different language to talk about it: food waste, food loss, kitchen waste, bio waste, etc. Two terms that are now more universally accepted:
Food loss: food that is lost in the supply chain before making its way to the market. Maybe they are eaten by pests, left to rot in the field due to a labor shortage for harvesting, or spoiled during storage and transportation. Examples: spoiled milk because of a break in the cold chain (temperature-controlled supply chain), or tomatoes crushed from improper handling or packaging.
Food waste: food discarded by retailers, restaurants, and consumers post-harvest and processing. You already know these: produce that doesn’t meet the “beauty standards” at grocery stores, restaurant leftovers not taken home, and that bag of lettuce that turned into lettuce soup in your fridge.
In developed countries like the US where we have better infrastructure, equipment and transportation, a greater share of the food is “wasted” (as opposed to “lost”), compared to less industrialized countries.
In the post below, I’ll try to be both colloquial and accurate so you don’t misunderstand I’m talking about.
Exactly how much food is wasted/lost varies by data source, but any way you cut it, a LOT of edible food goes uneaten.
- A widely cited 2014 USDA study estimated that 30% – 40% of the available US food supply is wasted, which equal about 133 billion pounds and $161 billion worth of food in 2010, or 360 grams (0.79 lb) per person per day. Again, note the word “waste”, as this study did not estimate food lost at the farm or farm-to-retail level.
- The same study (see p2 exhibit), as well as newer EPA data, show that food waste is the single largest category of trash going to landfills and incinerators. In 2015, 26% of municipal solid waste (by weight) was paper and cardboards, vs. 15% was food. But given some paper gets recycled, food becomes the no.1 contributor to landfills post-recycling (22% in 2015, to be exact.)
- A 2018 study by Conrad et al., which incorporates slightly more food items and likely more accurate measure of consumer food intake, found that about 422 grams (0.93 lb) of food per person per day (roughly 817 kcal) is wasted in the US, comparable in scale to the 2014 USDA study, as well as the 2017 study by Spiker et al. (Shout out to the authors Drs Conrad and Tichenor, who both graduated from my alma mater. Dr. Tichenor now teaches there too!)
- A 2009 study by Hall et al. found that per capita food waste has increased by 50% in the past 30 years, from 900 kcal/day in 1974 to 1,400 kcal/day in 2003. (You might notice that this caloric waste statistic is quite different from the numbers I cited above. I’ll spare you the details, but this study used different data sources and methods, so comparing them directly would be apple-to-orange. The important thing to note here is the time trend identified by Hall, who used consistent methodology across years.)
The healthier your diets are, the more you waste?
Conrad et al. found that unsurprisingly, fruits and vegetables (F&V) were wasted the most (by weight) out of the 22 food groups studied. (Of course, if you define “most” by monetary value, meat/poultry/fish might be first, per USDA). And largely because of this, the researchers found that higher diet quality is actually correlated with greater amounts of food waste, and greater amounts of wasted agricultural inputs (but less cropland waste).
The logic goes like this: F&V are fantastic for health, and they use less cropland to produce (such as compared to meat and dairy) but significant amounts of pesticides and irrigation water. And because they are wasted the most (from spoilage, etc), a healthier diet (which naturally includes a lot of F&V) is likely associated with more waste, and wasted pesticides and water. This finding is important in some nuanced ways:
- America definitely could go on a healthier diet, but blindly encouraging people to buy more F&V might lead to the unintended consequences of more food waste.
- Conventional wisdoms tell us that a plant-based diet is better for the environment, and by most measures (e.g., land, emission, etc), it certainly is. But this study shows us that F&V wasted in high proportions carry significant environmental impacts too, especially in the agricultural input department.
- What we ought to do, from a health and environmental perspective, is to simultaneously eat more F&V and waste less of them – which is v hard.
More food is wasted by you and me (don’t blame the retailers and the farmers), yet that doesn’t mean we are just horrible humans.
See this table I made using the USDA data. For just about every group, more food is wasted at the consumer end rather than the retail level. And as said by Dr. Sarah Taber, who famously debunked the ugly food movement: “Farms aren’t tossing perfectly good produce. You are.”
We don’t even really need data to tell us how we waste so much food, do we? “We were too busy to cook this week!” “I like the look of a full fridge!” “Half of this salad isn’t good to take home!” “Opps, forgot the leftover all the way in the back!” “This brown apple looks disgusting!” “Expired milk will kill me!” blah blah blah.
Ugh, humans, we are so terrible. But you know what, we are only human. While surely some people throw away food because they just don’t give a crap, powerful psychology is at play that explains our behaviors. For example, we all think we are doing a better job than the next guy. This 2015 survey from Johns Hopkins found that 73% of respondents reported that they waste less than the average American household, and only 3% reported wasting more – which, makes no sense mathematically (73% can’t be better than the average, because “average” by definition means 50%).
Additionally, we hold some stubborn and misled opinions about food waste. A 2016 study by Qi and Roe found that while 77% of Americans surveyed “feel guilty when throwing away food,” nearly 70% of them believed that throwing away food past the package date “reduces the chance someone will get sick” and 60% agreed that “some food waste is necessary to make sure meals taste fresh and good.” (I strongly recommend everyone check out this National Geographic article that summarizes common food waste perceptions.)
Understanding people’s perceptions and attitudes about why we throw away food is essential because they tell us how to fix this problem: some people need more education (e.g., about food labeling), and others may be nudged by better messaging (e.g., “reducing waste can save me $$”).
Ok, does this mean retailers share no blame? Absolutely not. Retailers and restaurants need to accept their fair share of the food waste problem, but the waste there is due to different factors, such as unpredictable consumer demand and inefficient business operations and replenishment policies. These problems require different solutions by government and the private sector (example), and EPA has launched some small but laudable goals and strategies.
Even if we really tried, we probably can’t (and maybe shouldn’t) get to zero waste.
Though we didn’t even get into the weeds on the environmental impact of our food waste problem in the US, one can imagine it is enormous. Yet the economics of food waste is important to grapple with, as there is a practical limit to how much food waste we can prevent, reduce and recover. Again, the USDA study categorizes these factors well, namely:
- “Technical factors”: most food is perishable. While much can be done to prevent waste and more helpful technology is emerging, some food will inevitably go to waste and spoiled food does pose safety concerns.
- “Temporal and spatial factors”: is it possible to rescue all wasted food given the distance they need to travel? Given how widespread yet dispersed our food waste issues are, can our efforts realistically reach millions of households?
- “Individual consumers’ tastes, preferences and food habits”: any parent knows how much food gets thrown on the floor by toddlers, and some people just really hate sandwich crusts! ¯\_(ツ)_/¯
- “Economic factors”: the cost, time, and resources needed to recover and redirect wasted food toward other uses. If they ultimately exceed the economic value of the food waste saved (even if we include the cost of the environmental externalities), can we justify that?
Obviously, the amount of our current food waste is nowhere near the level where these questions meaningfully matter (in my opinion). Yet it’s often good to temper expectations, and undoubtedly, these are all questions that businesses, policymakers and consumers already confront with on a smaller scale, whether intentionally or unintentionally. (Example: this might be a 2-seconds calculation in someone’s head: “there’s some food going bad in the fridge unless I eat it today. I know that throwing it away costs money and is bad for the environment, but I really just don’t have energy to cook right now, so I’m going to order a takeout – which costs more money – but it’s worth it to me.”)
Ok, thank you for making it to the end to my deep-ish dive (which my laptop keeps auto-correcting to deep dish). Many amazing books, like this one, have been written about this topic, which you should absolutely read. Tips to reduce food waste deserve its own post, so I’ll be writing about that another time. But if you simply can’t wait, well, just Google 🙂