Just how bad are ultraprocessed foods? Here are 5 things to know

May 13, 2024, 6:01 AM

Many people love the taste and convenience of ultraprocessed foods, but researchers are discovering...

Many people love the taste and convenience of ultraprocessed foods, but researchers are discovering some of these foods may affect your health negatively. Mandatory Credit: FreshSplash/iStockphoto/Getty Images via CNN Newsource

(CNN) — When you open a bag of nacho-flavored chips or cheese puffs, you probably know that you’re about to indulge in an unhealthy snack.

The dead giveaway? It’s the yummy, spicy, cheesy, neon-orange dust that coats each morsel and gets all over your fingers. Ditto for a frozen pizza and chicken nuggets.

But what about a granola bar? An applesauce pouch? String cheese? Flavored yogurt? Surely these foods — snacks that millions of children and adults eat every day — are not bad, right?

Well, it turns out that many fall under the category of ultraprocessed foods — depending on their exact ingredients. This type of food has been studied a lot lately, and the results aren’t great.

Ultraprocessed foods represent a relatively new way of categorizing foods. Proposed in 2009 by researchers at the University of São Paulo in Brazil, the system, called NOVA, is based not on what kind of food it is — meat, grains, vegetables, etc. — but rather on how processed it is.

NOVA separates foods into four groups, starting with natural and minimally processed foods in the first category to ultraprocessed foods, which use industrial formulations and manufacturing techniques, in the fourth.

“My operating definition for ultraprocessed (foods) is you can’t make it in your home kitchen because you don’t have the machinery and you don’t have the ingredients,” food policy expert Dr. Marion Nestle told CNN Medical Correspondent Meg Tirrell on the Chasing Life podcast recently. Nestle is the Paulette Goddard Professor of nutrition, food studies and public health, emerita, at New York University.

Listen to more of the conversation between Nestle and Tirrell here.

Ultraprocessed foods contain additives such as flavor enhancers, colors and thickeners — basically ingredients you wouldn’t usually use in your cooking. It makes them shelf-stable, easy to prepare (just heat and serve) and in many cases hard to resist. (The food industry pushes back on the NOVA system, saying there is no agreed-upon scientific consensus on the definition of ultraprocessed.)

Due to a confluence of historical, regulatory and economic factors, Nestle said, food companies in the 1980s “did a lot of work on trying to figure out what flavor and texture and color combinations would be most attractive to people and started producing foods that would make them lots of money.”

She said tens of thousands of new products have hit store shelves since then. “Most of them fail, but the ones that win, win big,” Nestle said.

Before you reach for that can of soda, bag of chips or frozen dinner, why not learn more about what you’re eating? Here are five things to know about ultraprocessed foods:

Ultraprocessed foods are linked to bad health outcomes

Eating a lot of ultraprocessed foods isn’t healthy.

“Now there have been more than 1,500 observational studies — all of them demonstrating a consistent finding, which is that eating ultraprocessed foods is linked to obesity, type 2 diabetes, heart disease, certain cancers, bad outcome from Covid-19, overall mortality,” Nestle said. “Any bad health problem you can think of that’s related to diet is related specifically to ultraprocessed foods.”

The most recent study, published Wednesday in The BMJ journal, analyzed more than 30 years’ worth of data and found that eating ultraprocessed foods was associated with a 4% higher risk of death by any cause, including a 9% increased risk of neurodegenerative deaths. Other studies have linked ultraprocessed foods to heart disease, type 2 diabetes, cancer and mental health disorders such as anxiety and depression.

Nestle pointed out that these studies have been observational and not designed to prove causation — that ultraprocessed foods caused these bad health outcomes.

“You can do that when you have a controlled clinical trial,” she said. “And guess what? We have one.”

Ultraprocessed foods cause weight gain

That one randomized, controlled clinical trial showed that ultraprocessed foods actually caused people to gain weight.

These types of studies are not easy or cheap to undertake, which is why they are not done more often. To conduct this one, Dr. Kevin Hall, a senior investigator at the National Institute of Diabetes and Digestive and Kidney Diseases, had 20 volunteers spend four weeks living at the National Institutes of Health Clinical Center in Bethesda, Maryland.

For two weeks, they ate a diet made up of 80% healthy ultraprocessed foods (think yogurt and whole wheat bread, not chips and soda). For the other two weeks, they ate a diet that contained no ultraprocessed foods. The diets were matched, among other things, for calories, sugar, fat, fiber and macronutrients. Participants did not know what exactly the study was measuring.

“We basically just asked people, you know, just eat as much or as little of the food that you’d like,” Hall told Tirrell. “You shouldn’t be trying to change your weight, (you) shouldn’t be trying to gain weight or lose weight. Just eat to the same level of appetite as you normally would.”

Researchers found that when the participants were on the ultraprocessed diet, they ate about 500 calories more per day than when they were on the minimally processed one. This difference in calories translated quickly to the scale. Participants gained on average 2 pounds during the two weeks on the ultraprocessed diet and lost 2 pounds on the minimally processed one. And their blood work showed lower markers of inflammation when they were on the latter.

“If you’re not familiar with nutrition research, you have no idea what an important finding this is,” said Nestle, who was not involved in the study. “Five hundred calories is huge.”

Hall said it’s unclear what drives people to consume more calories when they are on an ultraprocessed diet. “One of the things that we’re really interested in now,” he said, “is to figure out what the mechanisms were.”

Ultraprocessed foods are hard to avoid

Ultraprocessed foods are everywhere, and most of us consume them without even realizing it — even when you think you are eating something relatively healthy, such as baked potato chips or a peanut butter and jelly sandwich.

Using data from the National Health and Nutrition Examination Survey, researchers found that ultraprocessed foods make up more than half of American adults’ diets. For US children, that percentage is even higher, at 67%.

Ultraprocessed foods are cheap and convenient

Yup, that’s right: Truly eating “clean” costs more.

“To actually create the minimally processed menu, it was about 40% more expensive than the ultraprocessed menu,” Hall said. “That doesn’t even account for the time that it takes to make the foods, right? So, all those factors probably play a huge role in … the foods that we choose to eat in the real world.”

Not all ultraprocessed foods are bad

Some ultraprocessed foods can provide important nutrients, such as whole wheat bread and yogurt. And others, in Hall’s study, were shown not to increase caloric intake.

“The snacks were neutral in terms of how many calories (the participants) ate,” Hall said. “Which goes to show that not all ultraprocessed foods necessarily drive this effect.”

Hall’s team is conducting a new study to tease out which ultraprocessed foods are harmful and which are neutral, or even healthy.

Americans may soon get more help sorting through the health effects of ultraprocessed foods. The US Department of Agriculture and the US Food and Drug Administration will soon issue new Dietary Guidelines, which are updated every five years. Nestle said that the scientific advisory committee guiding this process has been asked to consider the connection between ultraprocessed foods and poor health outcomes.

We hope these five things help you understand ultraprocessed foods a bit more. Listen to the full episode here to find out how much ultraprocessed food Hall eats and what he feeds his children.

The-CNN-Wire™ & © 2024 Cable News Network, Inc., a Warner Bros. Discovery Company. All rights reserved.

KSL 5 TV Live


We're all guilty of slouching in our chairs. But did you know poor posture can cause serious health...

Emma Benson

Straightening up: How your posture affects your health

We're all guilty of slouching in our chairs. But did you know poor posture can cause serious health issues?

5 days ago

FILE: Marijuana plants are grown at Essence Vegas' 54,000-square-foot marijuana cultivation facilit...

Carla K. Johnson, AP Medical Writer

Daily marijuana use outpaces daily drinking in the US, a new study says

Millions of people in the U.S. report using marijuana daily or nearly every day, and those people now outnumber those who say they are daily or nearly-daily drinkers of alcohol.

5 days ago

A special humanitarian medical mission is underway in the Kingdom of Morocco involving 82 soldiers ...

Shara Park

Utah National Guard soldiers on humanitarian medical mission to Morocco

A special humanitarian medical mission is underway in the Kingdom of Morocco involving 82 soldiers from the Utah National Guard.

7 days ago

The first FDA-approved pill to treat postpartum depression was approved a few months ago, and it's ...

Jessica Guay, CNN

New hope for moms with postpartum depression

The first FDA-approved pill to treat postpartum depression was approved a few months ago, and it's already helping moms in the Pittsburgh area.

9 days ago

Diego Luna discusses his mental health struggles during his second season as a midfielder for Real ...

Emma Benson

‘It’s very difficult’: RSL’s Diego Luna opens up about mental health struggles

Luna, a California native and Olympic hopeful, is in his second season as a midfielder for Real Salt Lake. He admits the season was off to a rocky start. Pressures on and off the field, including becoming a father, were affecting his mental state.

9 days ago

TEMPE, ARIZONA - APRIL 17: Connor McDavid #97 of the Edmonton Oilers attempts a shot on goaltender ...

Stephen Whyno, AP Sports Writer

Connor Ingram wins the Masterton Trophy for perseverance and dedication to hockey

Connor Ingram, the goaltender for the Arizona Coyotes, has won the Bill Masterton Memorial Trophy after sharing his story with mental health struggles.

9 days ago

Sponsored Articles

Electrician repairing ceiling fan with lamps indoors...

Lighting Design

Stay cool this summer with ceiling fans

When used correctly, ceiling fans help circulate cool and warm air. They can also help you save on utilities.

Side view at diverse group of children sitting in row at school classroom and using laptops...

PC Laptops

5 Internet Safety Tips for Kids

Read these tips about internet safety for kids so that your children can use this tool for learning and discovery in positive ways.

Women hold card for scanning key card to access Photocopier Security system concept...

Les Olson

Why Printer Security Should Be Top of Mind for Your Business

Connected printers have vulnerable endpoints that are an easy target for cyber thieves. Protect your business with these tips.

Modern chandelier hanging from a white slanted ceiling with windows in the backgruond...

Lighting Design

Light Up Your Home With These Top Lighting Trends for 2024

Check out the latest lighting design trends for 2024 and tips on how you can incorporate them into your home.

Technician woman fixing hardware of desktop computer. Close up....

PC Laptops

Tips for Hassle-Free Computer Repairs

Experiencing a glitch in your computer can be frustrating, but with these tips you can have your computer repaired without the stress.

Close up of finger on keyboard button with number 11 logo...

PC Laptops

7 Reasons Why You Should Upgrade Your Laptop to Windows 11

Explore the benefits of upgrading to Windows 11 for a smoother, more secure, and feature-packed computing experience.

Just how bad are ultraprocessed foods? Here are 5 things to know