Food Waste: A Major Contributor to Climate Change
Dana Gunders was one of the first people to raise the alarm about how much food goes to waste and the subsequent impacts on our environment, food security, and the economy. As a Senior Scientist at the Natural Resources Defense Council, she authored the landmark report about food waste, called Wasted and testified before Congress on the topic. She is the author of Waste-Free Kitchen Handbook and currently serves as the Executive Director of ReFED, a collaboration of businesses, nonprofits, foundations, and government leaders that analyze the problem of food waste and develop practical solutions. Dana was interviewed by Arty Mangan of Bioneers.
ARTY MANGAN: Before 2012, there were very few people aware of the issue of food waste until you wrote a report about it. How did you get interested in the topic?
DANA GUNDERS: I was working on a sustainable agriculture project at the NRDC, and I was put in charge of the waste group, which was looking at plastics waste in farming. But as part of that research, I started stumbling upon the numbers of how much food was going to waste. We were trying to get farmers to be five or ten percent more efficient with their water and to use a little less fertilizer, but on the other hand almost half the food grown was not being eaten. I thought it was crazy that that much food was going to waste and no one was talking about it or working on it. That lit my fire on the topic.
ARTY: How is food waste defined?
DANA: There’s still not full agreement on how to define it; at ReFED, we define food waste as any food that goes to the landfill, incineration, down the drain, or does not get harvested. But we use the term “surplus foods,” which we define to be any food that goes unsold or uneaten across the food system including in homes.
Where does that food go? Only about three percent gets donated; most of it goes somewhere else whether it’s composting or anaerobic digestion or some of the waste destinations that I mentioned. Even if something is being recycled or composted, that’s not necessarily the best use of that product. So, we want to frame how much is surplus in the first place and then look at where it’s going.
ARTY: How much food is wasted?
DANA: At ReFED, we have done an updated analysis, and our estimate is that about 35 percent of food falls into that surplus category of being unsold or uneaten. When you look at just what’s going to the landfill or incineration that is about 24 percent.
ARTY: The book Drawdown: The Most Comprehensive Plans Proposed to Reverse Global Warming places food waste near the top as a contributor to greenhouse gas emissions. What are the impacts of food waste on climate?
DANA: The impacts are enormous. In their most recent analysis, Drawdown ranked reducing food waste as the number one solution to climate in one of their two scenarios. It takes a huge amount of resources to produce food, especially beef and dairy products. They have a really high greenhouse gas impact in their production. So, when we don’t use those products, all of that goes for naught. When food goes to landfills – in the US, food is the number one product entering landfills – it decays and produces methane, a powerful greenhouse gas.
The World Resource Institute predicts that we will need 56 percent more food in 2050 than we need today. Where is that food going to come from? Will we cut down more rainforests and native grasslands in order to plant more food, or will we just make better use of the food we’re already growing? By reducing food waste, we can reduce the amount of land that needs to be converted for agriculture and that is an important climate benefit.
ARTY: What are some of the other resources that are squandered when food is wasted?
DANA: Agriculture is the number one user of water around the world, so when we use water to grow something that doesn’t get eaten, it’s a huge waste. Our estimate is that for the US, the equivalent of about 14 percent of our freshwater goes to wasted food.
ARTY: I would guess that very few people know that food is the number one thing going to landfills. It’s an interesting commentary on our society. In a sense, affluence encourages waste. In what way does our culture encourage food waste?
DANA: In many different ways. In the US, food is a lower percent of our budget than in any other country. So, from a strictly financial incentive perspective, we don’t have the same incentive to conserve food as in other places.
Another is that we place a huge value on choice and on variety in our culture. The cost of that in terms of how much food we need to keep around so that we can have that choice and have that variety is enormous. The average grocery store carries about 50,000 different products, and they do that so you can walk in and have your choice any time of day. At its core is our expectations as consumers.
In our culture, we don’t have a mindfulness towards waste or wasting less than we do for some other issues. If I were to walk down the street and throw out a half sandwich on the sidewalk, people would think I was crazy, but if I throw it into the garbage, they wouldn’t think much of it. Littering has a really tall profile in our consciousness, but throwing food out doesn’t. We need to become more mindful as a society around the value and impact of what we’re throwing out.
ARTY: What are some of the practical strategies for reducing waste at home?
DANA: My favorite statistic that has been proven in several different studies is that 75 percent of Americans say they waste less than the average American. They don’t think they do it. The challenge is to convince people to manage their food with a mindset of not wasting.
The other challenge is that you really have to think upstream because once you have a rotten tomato or a science experiment in the back of your fridge, it’s too late. The way that you reduce waste is to actually manage your food better from the start. And that begins with shopping.
Strategy number one is to be realistic when you’re shopping. Shopping is the point when you commit to the food. Many of us are aspirational when we’re in the grocery store. We are going to eat better, we’re going to cook more, we’re going to feed our kids better, and then the realities of the week happen and some of the food doesn’t get used. So, being realistic when you’re shopping about the specific week ahead of you is a helpful way to reduce what eventually gets thrown out.
The best strategy is to plan your meals and to use a shopping list. That is extremely effective in wasting less food. It’s also a tall order for some people, so if that’s not you, then just taking a look in your cart before you check out and make sure you have an actual time you can imagine using that food that week. The number one strategy is to be realistic when you’re shopping.
A second is to freeze your food. The freezer is like a magic pause button, and you can freeze so many more things than you may realize. Fresh bread does really well in the freezer, especially if you slice it. Then you can take each individual slice out and toast it when you are ready to use it. Pasta, pasta sauce, cheese if you shred it, eggs if you take them out of the shell and scramble them but don’t cook them, milk as well. Leftovers, maybe you cooked too much and you ate some the next day, but now you’re sick of it. Just throw it in the freezer and take it out a week later.
Number three is understanding the dates on food – “sell by”, “use by”, and “best by.” Many people misinterpret those dates and throw food out prematurely. Those dates are not about the safety of the food and they’re not federally regulated. They’re a message from the brand that this food is at its top quality until that date. But they are not meant to say the food is bad or will make you sick after that date. Typically, if the food looks fine, smells fine, tastes fine, even after the date, it’s okay to consume.
The exceptions to that rule are those products that pregnant women should avoid, which are deli meats, ready-to-eat sandwiches, and sushi-type products.
ARTY: What are some of the ways state or federal policies unintentionally result in food waste?
DANA: Many food safety laws are creating quite a bit of waste. For instance, you can’t donate anything that’s been out for more than four hours. Food safety laws tend to be very local per state, so it varies, but generally speaking, the food safety rules are very cautious and very broad. If anything is left out for four hours or needs to be maintained at X temperature, and if it’s been three degrees below that, then you can’t donate it or sell it.
We now have a lot more precise technology to monitor temperature exposure of foods than we used to, but I don’t think the food safety laws have caught up with that. They are still very broad; I think there’s an opportunity for the rules to be more precise by monitoring temperature.
Around the country, different states have different rules. One of the most egregious is Montana, which requires a sell-by date on milk that is 12 days after it’s produced, whereas most milk gets a date that’s between 21 and 28 days after it’s produced. Montana also requires milk to be discarded after that date. So, you have a huge amount of milk going to waste in Montana because of that law.
Mislabeling – labels have to be right, and so they can cause waste if, for example, the label didn’t include an allergen that was supposed to be included.
ARTY: What are some current policies that are successfully reducing the problem?
DANA: One of the key policies that we think is very low-hanging fruit is a federal law that would standardize date labeling to address some of the confusion and create two labels; one that indicates the date about the quality of the food and a second that indicates the date about the safety of the food.
There have been bills introduced on this. They include a clause that says that no state can restrict the sale of any product because of the quality date. If it’s just about the quality of the product that’s not going to make anyone sick, there should be no reason that you can’t sell that product even after the date.
It also enables education of consumers on what these dates really mean. If you see a date that says “best before” or “best if used by”, those are recommendations. It’s not about the safety of the food. If it looks fine, smells fine, tastes fine, then you can eat it. But if you see a label that says “use by” – which is currently proposed – that indicates that there’s an increased risk if you consume the food after that date, so be more careful. Right now, we can’t say that definitively because there’s no common definition or common usage around the country.
There are two federal bills that were recently introduced; one is called the Zero Food Waste Act – introduced in both the House and Senate – that puts funding into state and local and even nonprofit efforts to reduce food waste in a variety of ways. The second one is called the Compost Act, which provides funding for composting and infrastructure. We’ll see where they go.
ARTY: Beyond policies, are there any other innovations in the food system that would reduce food waste?
DANA: We talked about grocery stores having to manage 50,000 different products; that’s a big data problem. The application of machine learning is doing a very good job of identifying patterns for each of those products that perhaps the human buyers can’t do as readily. They track sales impacts, for example, if cheese is on sale, you may wind up selling more pears. Things like that help make inventory control more efficient and reduce waste.
There are some apps that have been sweeping across Europe and now in the US as well that help both grocery stores and restaurants do flash sales via the app for products that they’re about to throw out or take off their shelves. For example, the restaurant that has six sandwiches at the end of the night leftover can now sell them via this flash sale app rather than throwing them out. Similarly, grocery stores, right before they’re about to take a product off the shelf, can do a flash sale via an app. The businesses don’t feel like they’re cannibalizing their own sales, but rather feel like they are bringing new people into the store.
There are hyper-spectral imaging technologies now that can very quickly evaluate how ripe a fruit is. It essentially sees inside of foods and so you can tell if an avocado or strawberry has been bruised, or has a longer shelf life, or if it’s riper than you think it is, etc. That information can then be used to route some products to shorter shelf life destinations and other products to longer destinations.
There are also innovative business models such as Imperfect Foods and Misfit Markets, and Full Harvest that are creating an alternative marketplace for some of the excess produce and other foods as well.
Over the pandemic, we saw those companies really shine because they can take just about anything and offer it up on their sites and send it to you. When the pandemic first hit, they were selling popcorn because all the movie theatres had closed down and the distributors were sitting on extra popcorn. Imperfect Foods was able to sell the popcorn in bags to people in their homes. They were able to also take something like 40,000 extra cheese and cracker trays from United Airlines and sell them. That level of flexibility in a business model is really useful when it comes to reducing food waste.
ARTY: How is ReFED addressing the problem?
DANA: One of the biggest challenges on this topic is people don’t know what to do, they don’t know where to start, and they don’t know what’s going to be most effective. We provide data to help people identify and prioritize actions that they can take to reduce food waste. That looks very different if you’re a farmer or if you’re a restaurateur or somebody in your own home. So, we try to quantify the impacts of different solutions.
Our work really has three components. One is to provide the data and insights that will help drive action. The second is to bring more capital and innovation into the space, private investment, philanthropic and public funding that can help scale up solutions. The third is to engage stakeholders. We really try to be a hub and connector in this space to help convene and drive action, because there’s so many different entities from municipal governments to private investors to food companies working on the topic.