Ultra-processed foods are designed to be cheap, convenient, and keep us energized and full until the next meal.
But increasingly, health experts are discovering these foods aren’t great at keeping us satisfied, or even alive, long-term.
A new study from researchers at the Centers for Disease Control suggests that many Americans are relying on junk foods to stay alive, and it’s damaging their hearts.
It may be the case that the more factory-made ultra-processed food we eat — like granola bars that last for months on the shelf, canned ravioli loaded with thickeners and stabilizers, and soft drinks sweetened with high-fructose corn syrup — the weaker our hearts perform.
“These foods are engineered to taste so good,” study author Dr. Zefeng Zhang, an epidemiologist at the CDC, told Insider, before his study came out in the American Journal of Clinical Nutrition in October.
But that gustatory excitement comes at a hidden cost.
Ultra-processed foods are often not only nutrient-poor, they also prompt people to keep eating after they’re full. This may be because the foods override natural fullness sensors in the body, and also because they are designed to be eaten and digested so quickly.
“Ultra processed food often lacks fiber,” Zhang said. That means people “don’t feel as full as with real food.”
Zhang and his colleagues discovered a huge number of people are relying on ultra-processed foods for sustenance
Zhang’s study relied on rigorous national health and nutrition surveys carried out every year by the CDC, in which researchers ask people questions about what they eat, and also take stock of their overall health with a physical exam.
For the study, Zhang and his team of four other investigators looked at more than 11,200 people surveyed across the US between 2011 and 2016. The study participants were not a perfectly accurate representative sample of Americans, demographically speaking. Researchers asked more of their questions to minority, low-income, and elderly people across the US, hoping to gather useful information about their respective health issues, which haven’t been well studied or understood in the past. (For example, about 25% of the original study respondents were over 60 years old.)
They discovered that many of these people are relying on ultra-processed goods to stay alive. More than half of the daily calories of the people surveyed came from ultra-processed foods.
The team’s work also suggests people’s hearts aren’t thriving on these convenience foods. For every 5% increase in processed foods consumption, there was a corresponding .13 decrease in a person’s cardiovascular health score. In other words, the dose of processed foods people are eating appears to really matter for their heart health.
Researchers still don’t know exactly why processed food is so bad for our health. But what is clear, from Zhang’s research and other studies, is that people who eat more processed foods tend to also have more heart issues, die earlier deaths, contract more cancers, and gain extra weight.
But processed foods are also useful, especially when people are busy, or where money is tight.
“Ultra-processed food has a lot of advantages,” US National Institutes of Health nutrition researcher Kevin Hall previously told Business Insider, when his blockbuster study was released, suggesting people who rely on ultra-processed foods may eat about 500 more calories every day.
“It’s cheap. It sticks around for a while. You don’t have to have all the fresh ingredients on hand, which might spoil. You don’t have to have all the equipment to prepare these meals from scratch.”
Ultra-processed foods tend to have at least five ingredients
Scientists typically define ultra-processed food as “industrial formulations typically with five or more — and usually many — ingredients.”
Staples like vegetables, beans, meats, cheeses, and other produce are all examples of unprocessed, or minimally processed foods. Ultra-processed foods have been broken down from these whole or fresh forms, and transformed into convenience foods.
“Ultra processed foods often have high amounts of added sugar, sodium, and saturated fat, as well as chemical additives,” Zhang said.
These foods may be treated with thickeners, colors, stabilizers, glazes, and additives. They could be extruded, molded or pre-processed for frying, before they’re packed in cans or wrappers. They might contain high-fructose corn syrup, protein isolates, or interesterified oils (replacements for trans fats, which are now widely banned).
Examples include many packaged granola bars and breakfast cereals, carbonated soft drinks, candy, margarine, energy drinks, flavored yogurts, chicken nuggets, and hot dogs.
This research did not explore in depth which ultra-processed foods might be the most harmful, and it’s difficult to tease out how much people’s diet choices might interact with their other life choices or circumstances (like activity level, access to food, income, or family history).
It’s also tough to know from a study like this if there might be some degrees of quality difference between different processed foods, but evidence suggests they’re not great overall.
Even small changes in snacking habits can make a difference
Zhang suggests that even a small daily change to an eating routine could help.
If a 5% increase in ultra-processed foods can harm heart health, then a minor decrease in ultra-processed food consumption, like replacing a packaged snack with some fruit, vegetables, or nuts, might help your heart.
“Grab a snack on whole grain bread,” he suggested, instead of opting for the white fluffy stuff (just make sure it includes the words “whole grain” and is not a refined grain product.)
He says even if you “change a little bit,” in a way that your wallet and schedule can afford, those subtle differences can add up over time to better overall health.