Ultra-processed American foods are extremely unhealthy. Here’s what you need to know | Well actually

Buying yogurt, bread, and granola bars may seem like a healthy decision. Dairy seems to be a calcium-boosting choice for kids, whole-grain bread is better than white bread, and granola bars seem much better for you than chips or gummy bears — and in many ways, they are. are.

But a growing number of foods sold in grocery stores — even those that appear healthy — are what scientists now call “ultra-processed”: fruit yogurts loaded with sugars, flavorings and thickeners like guar and locust bean gum; or packaged bread, with ingredients like soy lecithin and monoglycerides slipped in alongside the flour and water.

These industrially formulated products, which are often high in fats, starches, sugars and additives, now account for 73% of the U.S. food supply. Yet research increasingly links ultra-processed foods to myriad health problems, such as diabetes, obesity, cancer and depression. Despite these risks, the average American gets more than 60% of their daily calories from ultra-processed foods – more than in any other country in the world.

A new way of thinking about nutrition

The term “ultra-processed foods” first appeared in 2009 when Brazilian nutritionist Carlos Augusto Monteiro published an article that made a bold argument: “The problem is not so much the food, nor the nutrients, as the transformation. »

Most foods are processed in some way, whether it’s an apple waxed to shine extra at the grocery store or milk pasteurized for safety. Processing in itself isn’t bad – in fact, vitamin fortification and preservation techniques (like canning and fermentation) have made the food supply safer and rid much of the world of hunger by ensuring nutritious, shelf-stable foods are available all year round. round.

But while some foods are “minimally processed” (like shelled nuts or washed vegetables) and others are simply “processed” (think canned fish, frozen vegetables, or cheese), Monteiro identified another type of processing that emerged in the 1980s and 1990s: ultra-processed foods (like many breakfast cereals, packaged snacks and sugary drinks) – which, he writes, are industrially formulated to be “edible, tasty and habit-forming”.

For years, nutritionists have focused on the nutrients in food: potassium and fiber are good, while sugar, salt, and saturated fat can be a concern in large amounts. But in the early 2000s, Monteiro and his colleagues at the University of São Paulo noticed that rates of diet-related diseases (like obesity and type 2 diabetes) were increasing, even though Brazilians were buying less sugar.

They argued that while eating large amounts of sugar wasn’t necessarily good for consumers, there was much more to it than that. Even though fruits, like mangoes and bananas, are high in sugar, no one eats a dozen of them in one sitting. But something about ultra-processed foods, like packaged candy bars and cookies, made it difficult to eat just one. Scientists will later wonder whether this has to do with the “food matrix” or the chemical and molecular structure of foods: the sugars in whole foods like fruit are packaged alongside dietary fiber and vitamins that make them recognizable and more satisfying for our body.

A growing body of evidence

Since Monteiro and his colleagues first defined ultra-processed foods, or UPFs, dozens of researchers have wondered: What effect do they have on the human body? And why?

For years, scientists have conducted observational studies on the associations between diet and health outcomes. But the most compelling evidence that UPFs actually did something different from other foods finally came in 2019 when Kevin Hall, a senior scientist at the National Institute of Diabetes and Digestive and Kidney Diseases, published the first randomized study and controlled on ultra-processed foods. .

For four weeks, 20 healthy adult volunteers agreed to follow an ultra-processed or minimally processed diet for two weeks, then switch to the other diet. Importantly, the diets were matched nutrient for nutrient – ​​those on an ultra-processed diet would consume as much sugar, fiber, fat, salt and carbohydrates as those on a minimally processed diet – and both groups were encouraged to eat as many or as many nutrients as possible. little as they wanted.

At the end of the study, Hall found that participants had consumed 500 more calories each day during the ultra-processed diet weeks and gained more weight. Something about ultra-processed foods has made people hungry and want to eat more.

This is a monumental discovery at a time when the food industry was funding research aimed at shifting the blame for obesity from diet to exercise.

Since then, the evidence that ultra-processing has negative health effects has continued to grow.

A 2022 study published in the British Medical Journal found that men (but not women) who consumed a high amount of UPF had a 29% higher risk of colorectal cancer (findings that attracted particular attention then that the rate of colorectal cancer in young adults is increasing). At the European Society of Cardiology Congress in Amsterdam in August 2023, a research team presented a study concluding that a 10% increase in daily UPF intake was linked to a 6% increase in the risk of cardiac disease. And in September, a Harvard study found that women who ate the most UPF were 50 percent more likely to develop depression than those who ate the least.

Earlier this year, researchers from Deakin University in Australia, Johns Hopkins University, the Sorbonne and others published a general review of existing research on the health impacts associated with food consumption ultra-processed. They found that UPFs were directly linked to 32 adverse health outcomes, including hypertension and anxiety. The article suggests that consumption of ultra-processed foods is strongly linked to cardiometabolic diseases, common mental health problems and higher mortality rates.

“Although the associations between consumption of ultra-processed foods and other health conditions are less certain, such as respiratory and gastrointestinal health, certain cancers, and intermediate cardiometabolic risk factors, this does not mean that these links are unimportant,” said postdoctoral researcher Melissa Lane. researcher at Deakin University’s Food and Mood Center and one of the study’s authors, said in an email. “Rather, they highlight areas where further study is needed to clarify these potential impacts.”

Because UPFs are made up of dozens of ingredients that are relatively new to the food supply, “the possibilities for physiological effects are endless,” said Josiemer Mattei, a professor of nutrition at the Harvard TH Chan School of Public Health.

Why do the UPF do what they do?

The concept of ultra-processed foods has been a useful lens that scientists can use to assess the impacts of industrially manufactured products, said Leigh Frame, executive director of the Office of Integrative Medicine and Health at George Washington University. But as researchers dig deeper, they begin to distinguish between types of UPF.

Last year, a Harvard study found that refined breads, sauces, condiments, artificially sweetened and sugary drinks, animal products, and ready-to-eat meals were most closely associated with higher risk. high risk of developing type 2 diabetes (as opposed to type 2 diabetes). other UPF such as cereals, wholemeal breads, fruit products and yogurts). Similarly, another Harvard study published last year found that consumption of UPF – but particularly artificially sweetened foods and drinks – was associated with a risk of developing depression.

“One of the challenges is that UPF includes all sorts of ingredients and compounds, and these can act in many ways in the body,” Mattei said.

As scientists try to delve deeper which UPFs have the worst health impacts – to ask the question Why UPFs do what they do — they also try to conduct more rigorous research, like Hall’s study (although Mattei notes that “as evidence accumulates on the potential adverse effects of UPFs,” he may become unethical to conduct future trials). Stronger data could ultimately shape nutrition policy in the United States.

To change food policies in the United States, “you basically have to have a randomized controlled trial that definitively shows that this is happening, and we don’t really have that yet,” said Frame, who says the National Institutes studies of Health are getting closer. However, given the poor state of funding for nutrition science in the United States, she says, the bar is high.

Although researchers are wary of UPFs, Frame says she doesn’t think any food should be 100 percent banned. “Such forbidden food only causes problems, including increased desire,” she said. “I’m more concerned about the overall diet than any individual food.” If people can increase the amount of minimally processed whole foods they eat relative to UPF, that’s a win.

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