During a university lecture several years ago, we were shown a painting of a 36-year-old man living at the dawn of the 19th century who weighed more than 700lb. His body, a professor said, was an example of “food waste”.
This framing may seem shocking, as it did to us in the audience, but the idea is not necessarily fringe. There is a growing body of literature focused on fat people as “metabolic food waste”.
The logic goes like this: weight is directly linked to how much people eat, eating too much food has a measurable environmental impact and anyone who is deemed to be overweight is, therefore, a bigger burden on the environment.
This idea can now be found in scientific studies. In May, a paper published in Nature argued that overeating – assumed to be the reason for increasing average body size – has a large environmental impact.
The researchers came up with a calculation for “excess calories consumed by obese and overweight people” in Italy. They then worked out the greenhouse gas emissions from the production and consumption of this food.
The study concluded in Italy led to “an additional emission burden of about 24% and 12% for obese and overweight adults [respectively]”. It called for more attention on preventing obesity to help decrease emissions.
Geography professor Julie Guthman writes in her book Weighing In that as obesity was turned into a crisis, some environmentalists started to see reducing environmental impacts as more to do with individual choices and action – including around food consumption and body size – than broader societal change.
In this worldview, shrinking waistlines and lower environmental footprints become desirable twin goals. Individual food choices are highlighted and thinness is put on a pedestal at the expense of focusing on the social and environmental policies that shape people’s diets and environments.
“The fat body is seen as evidence of food system failure,” said Virgie Tovar, a fat activist and writer. “People who are perceived as ‘hurting the planet’ become vilified and, when it comes to higher weight people, there’s already this bigotry in place that says fatness is about excess and is about overconsumption that is largely about an immoral relationship to food and food systems.”
Tovar and many other experts say that much of the way fatness is popularly conceived stems from a reliance on the body mass index (BMI) measurement system.
Categories such as “overweight” and “obese” are calculated from people’s BMI, a metric devised in the 19th century and based on white men’s bodies. BMI does not account for differences in body types across race and gender, yet it is “weaponized”, Tovar said, to marginalize people – disproportionately Black women – whose bodies don’t conform to it.
The arbitrary nature of these metrics was illustrated by a 1997 decision to adjust the cutoffs for BMI categories, newly categorizing several million people as “obese” overnight and contributing to obesity’s “epidemic” status.
Dr Katherine Flegal, an epidemiologist and former Centers for Disease Control and Prevention scientist, says while “overweight” and “obesity” are defined in terms of BMI, it’s not clear that a higher BMI means someone is consuming more food. This poses a problem for sustainability metrics such as “metabolic food waste”, which use BMI to calculate “overeaten” food’s environmental impact.
Body size cannot be reduced to a “calories in, calories out” framing. “There is data showing that, at a population level, it’s not like people in bigger bodies are eating thousands of more calories every day,” said Dr Jennifer Brady, director of the nutrition and dietetics department of Acadia University.
Recent research points to a host of other reasons, including the endocrine-disrupting chemicals found in everything from food packaging and plastics to personal care products, as well as other additives, which play a role in determining body size. Fat people have also always existed: “We are a natural part of human diversity,” Tovar said.
Linking obesity to environmental harms becomes yet another way in which people are stigmatized due to their body size, say experts, in addition to the discrimination they experience in workplaces, healthcare settings and public spaces.
“There is this consistent effort to link the behaviors of people who are seen as socially undesirable to consequences being experienced by society as a whole,” said Marquisele Mercedes, a public health and anti-fat bias researcher.
This thinking reaches into policy discussions. A report from last year’s UN food systems summit says a main driver of obesity is “excessive consumption of energy-dense foods” and refers to the “related problems of food waste caused by the production and consumption of cheap but non-nutritious foodstuffs”.
A 2019 report from the World Resources Institute modeled a series of diets for reducing emissions, one of which was the “skinny diet” – cutting calories with the aim of “a 50% reduction in the numbers of obese and overweight people”. While the authors concluded this diet would not be an important strategy for closing the emissions gap, the fact they spend time considering it shows the popularity of this framing.
“People are held individually responsible for ‘fixing’ their bodies, and the focus becomes the individual and not social structures – substantive things like environmental toxins and water systems get thrown out of the picture”, said Dr Emily Yates-Doerr, an anthropologist who has studied the racialized impacts of obesity interventions.
People have focused on eating, says Guthman, “because it’s the easiest way to think about food systems and the easiest thing to do, is to say, ‘OK, I’m going to try to change people’s dietary habits’, even though it’s never easy to do that”.
While focusing on individual diets may not be an effective solution to addressing the environmental impacts of food systems, what it is effective at doing is scapegoating certain bodies for societal problems like climate change. “Instead, we should be asking how to design food and nutrition policies that inspire collective action and structural change,” Yates-Doerr said.
Guthman calls for much tighter restrictions on toxic agricultural chemicals and harmful food additives. Involving affected community members in policymaking processes is important to creating more relevant and impactful policies, Yates-Doerr added.
“When we’re talking about sustainability, people who are clearly concerned about the planet need to have this conversation in a way that incorporates fat people as fully human, not as failed thin people,” Tovar said.
Austin Bryniarski is a food systems researcher and writer and works at the Public Justice Food Project.
Samara Brock has worked for more than 15 years in sustainable food systems for NGOs, foundations and government and is completing a PhD focused on organizations working to transform the global food system.