If you look at a package of M&Ms, one of the most popular candies in the US, you’ll see some familiar ingredients: sugar, skimmed milk powder, cocoa butter. But you’ll see many more that aren’t so recognizable: gum arabic, dextrin, carnauba wax, soya lecithin and E100.
There are 34 ingredients in M&Ms, and, according to Mars, the company that produces the candy, at least 30 countries – from Ivory Coast to New Zealand – are involved in supplying them. Each has its own supply chain that transforms the raw materials into ingredients – cocoa into cocoa liquor, cane into sugar, petroleum into blue food dye.
These ingredients then travel across the world to a central processing facility where they are combined and transformed into tiny blue, red, yellow and green chocolate gems.
It’s becoming better understood that food systems are a major driver of the climate crisis. Scientists can examine deforestation for agriculture, or the methane emissions from livestock. But the environmental impact of ultra-processed foods – like M&Ms – is less clear and is only now starting to come into focus. One reason they have been so difficult to assess is the very nature of UPFs: these industrially made foods include a huge number of ingredients and processes to put them together, making it nearly impossible to track.
But it doesn’t mean it’s not important. As UPFs take over US grocery store shelves and diets– they now comprise 70% of food sold in grocery stores, and more than half of calories consumed – experts say that understanding their environmental toll is critical to build a more climate-friendly food system.
What we know
While scientists are only starting to examine the environmental impact of UPFs, what’s already known about them is worrisome.
“The more processed foods are, the more deleterious they are to human health and the environment,” said Anthony Fardet, a senior researcher at the French National Institute for Agriculture, Food and the Environment. The main reason, he explains, is that the ingredients are so energy intensive. When combined, the toll balloons.
Take M&Ms. The first step in creating the candies is farming for cocoa, sugar, dairy and palm.
It has been well-documented that agriculture for ingredients like cocoa drives ever increasing rates of deforestation across the globe. Since 1850, agricultural expansion has driven almost 90% of global deforestation, which has been responsible for 30% of global greenhouse gas emissions. Mars corporation has been called out in the past for the cocoa farming practices in their supply chain, and have since created sustainability plans, but these fail to address that large-scale agricultural practices like cocoa farming are, at their core, unsustainable.
Then there’s sugar, milk solids and palm fat – also major greenhouse gas emitters.
On top of that are the industrially made ingredients like food dyes – perhaps the signature of ultra-processing – which M&Ms contain 13 different types of. Blue M&Ms are colored with dyes E132 and E133; these dyes are mostly made in food dye manufacturing hotspots India and China, via a chemical reaction of aromatic hydrocarbons (which are petroleum products) with diazonium salt, catalyzed by the metals copper and chromium.
M&Ms for sale in Orlando, Florida, in 2019. Photograph: Jeff Greenberg/Universal Images Group via Getty Images
Creating soya lecithin, an additive made from soybean oil that’s used to change the consistency of chocolate, requires steps like degumming in a hot reactor, chemically isolating phospholipids, decolorization using hydrogen peroxide and drying under vacuum pressure. And dextrose, a sweetener, starts off as corn that gets steeped in acid before being milled, separated and dried. From there, it’s broken down into smaller molecules using enzymes and acids, and then recrystallized.
Mars declined to comment for this story.
While ultra-processed chocolate products are some of the worst offenders, other kinds of UPFs are taxing on the environment as well. Take for instance Doritos, which have 39 ingredients. Corn is the main ingredient, and for every acre grown, 1,000kg of carbon dioxide is emitted to the atmosphere. Like Mars, Pepsico, which makes Doritos, has developed its own sustainability promises, but many of these promises are underpinned by practices that are considered greenwashing, like “regenerative agriculture”. In reality, these sustainability promises undercut the dire need to better understand how UPFs affect our global climate.
As a result, some experts have started to calculate the environmental toll of UPFs.
CarbonCloud, a Sweden-based software company that calculates the emissions of food products, analyzed carbon disclosures from Mars, and estimated that M&Ms generate at least 13.2kg of carbon equivalents per kilogram of M&Ms produced. Mars produces more than 664m kg of M&Ms in the US each year, which would mean that if CarbonCloud’s calculations are accurate, the candies emit at least 3.8m tons of carbon dioxide – making up 0.1% of annual emissions in the US. (Mars does not report emissions by product, but according to their 2024 emissions report, they emitted 29m tons of carbon dioxide across the company.)
But this is only an estimate based on publicly available data; the true cost is probably much higher, experts say. There’s a “black box” when it comes to carbon accounting in the processed food industry, says Patrick Callery, a professor at the University of Vermont who researches how corporations engage with the climate crisis. “There is so much uncertainty as supply chains get complex.”
What we don’t know
Getting an exact measure of the environmental toll of UPFs is nearly impossible, given that, definitionally, UPFs consist of many ingredients and a high volume of opaque processes. Ingredients aren’t just mixed together like one would do to make a stew at home. Instead, these ingredients are chemically modified, some parts stripped away, and flavors, dyes or textures added in – and it’s unclear what the cost of these processes are because so many suppliers and components are involved.
Another reason is that all UPFs (again, definitionally) are the creations of food companies that have little incentive to disclose their environmental footprint and may not fully understand it to begin with.
For instance, Mars itself doesn’t farm cocoa, but instead relies on hundreds of farms that don’t always have accurate carbon accounting measures in place. This means that emissions from big food corporations may be underreported. David Bryngelsson, co-founder of CarbonCloud, said that corporations “don’t have actual data, so they use emissions factors, which are guesses”.
Callery says that corporations provide reports on simple things like transportation, which are easier to calculate, and often omit or convolute the agricultural emissions of their product. After all, reporting high emissions goes against the interests of large food corporations, so the complex calculations needed to determine the carbon footprint of large-scale agriculture and multi-step industrial chemical processes used to make UPF ingredients remain un-researched.
“The main point of ultra-processed foods is money,” said Fardet, pointing out that they’re designed to be attractive, easy and pleasurable to eat.
“Most of the people in the [food industry’s] value chain don’t care about climate change from an ideological point of view, but they do care about money,” said Bryngelsson. He explains that to shift those incentives, the value of foods and ingredients would need to incorporate their impact on our shared climate. But that would require government regulations and financial penalties based on the true environmental cost of UPFs, says Bryngelsson.
Why it matters
At just under $2, the price of M&Ms at the grocery store hardly reflects their true cost on the environment. But to address these problems with ultra-processed foods, more than just a few tweaks to the ingredient list are needed.
“Reducing the salt, or sugar of just one product is just greenwashing,” said Fardet. “We need to change the whole picture.” To do that, he suggested consuming more locally sourced, whole foods, which often take much less energy and transit to produce, and therefore have a much smaller carbon footprint.
Specialty goods that can’t be sourced locally, like chocolate, should make up a small fraction of our diet and come from traceable and ethical supply chains.
That’s not easy for all Americans, given the rising cost of food and the prevalence of food deserts and mediocre food retailers across the US.
That’s why it can’t just be up to individuals to make environmentally (and health) conscious choices, experts say. Instead, large food corporations need to be held responsible for the burden they place on society – particularly as it pertains to climate change. Sustainability practices, like the “Cocoa for Generations” plan outlined by Mars, or Pepsico’s “Pep+” initiatives are Band-Aids on broken bones. Large food corporations need to be phased out to make global food systems sustainable.
But perhaps more important is to change our understanding of the hidden costs of ultra-processed foods, says Fardet, whether it’s at home, in schools or through the banning the marketing of UPFs to children. Our food systems, Fardet said, “are absolutely not normal. The whole industry should pay the hidden costs.”
