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A new study of 45 meta-analyses on almost 10 million people found that eating ultraprocessed foods increases the risk of getting or dying from dozens of serious health problems.
“We found consistent evidence linking higher intakes of ultra-processed foods with over 70% of the 45 different health outcomes we looked at,” wrote senior author Wolfgang Marx in an email. Marx is a senior research fellow at Deakin University in Geelong, Australia, and works at the Food & Mood Center.
Heinz Freisling, a scientist at the International Agency for Research on Cancer of the World Health Organization, said in an email that eating about one serving, or 10 percent more ultraprocessed foods per day, was seen as a higher diet.
Freisling, who wasn’t involved in the study, said, “This proportion can be thought of as ‘baseline.’ For people who consume more than this baseline, the risk might go up.”
The researchers gave each study a score based on how strong or believable the evidence was. Scores ranged from “strong” to “no evidence” or “weak.” The review only looks at studies that came out in the last three years. The writers say that none of the studies were paid for by businesses that make ultraprocessed foods.
Author and lead author Dr. Melissa Lane, a postdoctoral research fellow at Deakin, said in an email, “Strong evidence shows that a higher intake of ultra-processed foods was associated with a about 50 percent higher risk of death from cardiovascular disease and common mental disorders.” Heart attacks, strokes, clogged arteries, and peripheral artery disease are all types of cardiovascular illness.
According to a study released Wednesday in the journal The BMJ, there was strong evidence that eating a lot of ultraprocessed foods could raise the risk of worry by up to 53% and the risk of dying young from any cause by 20%.
“It’s not a surprise that many studies show a link between eating ultraprocessed foods and a higher risk of different diseases,” said Fang Fang Zhang, an associate professor and chair of the division of nutrition epidemiology and data science at Tufts University in Boston and an expert in cancer epidemiology. She had nothing to do with the new study.
Zhang said, “Ultraprocessed foods are high in calories, added sugar, and sodium and low in fiber.” “We already knew that all of these things can lead to heart and metabolic health problems, weight gain, obesity, type 2 diabetes, and high blood pressure.”
However, Zhang had doubts about the results of studies on anxiety and sadness, which usually only include people who have already been diagnosed with those illnesses.
“People who are depressed or anxious may seek out ultraprocessed foods for a variety of reasons, such as to feel better,” she said. “Eating highly processed foods might not make you more likely to become depressed; we can’t say for sure.”
Has a mixed effect on some health problems
A study found strong proof that eating more ultraprocessed foods increased the chance of being overweight by 55%, having trouble sleeping by 41%, getting type 2 diabetes by 40%, and being depressed by 20%.
The study found that there wasn’t much evidence to suggest a link between eating ultraprocessed foods and asthma, gut health, or cardiometabolic risk factors like high blood fats and low amounts of “good” HDL cholesterol.
The study also found that there was little to no proof that ultraprocessed foods are linked to cancer. Zhang, who has studied the link between ultraprocessed foods and cancer, says that’s strange.
Being overweight puts you at risk for 13 different types of cancer. “Ultraprocessed foods make you gain weight, and being overweight makes cancer worse,” she said. Zhang co-wrote a study in August 2022 that found guys who ate the most ultraprocessed foods of any kind were 29% more likely to get colon cancer.
Research on ultraprocessed foods is still very new, which could explain why the result was so surprising, said Mathilde Touvier, research head at the French National Institute of Health and Medical Research and co-author of the study.
“We definitely need more studies to be able to improve the weight of evidence for things like cancer,” Touvier said. Touvier is also the lead researcher of the NutriNet-Santé cohort, which is a long-term study of the link between diet and health.
It’s not because there’s nothing there, she said; it’s just that we need to do more study.
The steps used to make ultraprocessed foods
Head of the Center for Epidemiological Studies in Health and Nutrition at the University of São Paulo in Brazil and a nutrition researcher, Dr. Carlos Monteiro, said that ultraprocessed foods are more than just “modified” foods. He had nothing to do with the new study.
“They are made up of cheap, often chemically changed ingredients like modified starches, sugars, oils, fats, and protein isolates, with little to no whole food added,” wrote Monteiro, a nutrition and public health professor, in a linked opinion.
When Monteiro created NOVA in 2009, a way to divide foods into four groups, he came up with the name “ultraprocessed food.” Group 1 includes things that haven’t been processed or have been processed very little, like fruits, veggies, eggs, and milk. Ingredients for cooking, like salt, plants, oils, and other similar things, are in Group 2. Processed foods that blend foods from groups one and two are in group three. Examples of this are canned goods and frozen veggies.
Ultraprocessed foods are in the fourth group. Monteiro said that they taste good and are appealing because they contain fake flavors, colors, thickeners, and other ingredients that have been “linked by experimental and epidemiological evidence to imbalances in gut microbiota and systemic inflammation.”
In the editorial, Monteiro said, “There is no reason to believe that humans can fully adapt to these products.” “Depending on how sensitive they are and how much ultra-processed food is eaten, the body may see them as useless or harmful, which could weaken or damage its systems.”
Researchers, scientists, and public health officials have become more worried about the rising number of ultraprocessed foods in the US, Australia, the UK, Canada, and many developing countries since Monteiro’s description came out.
“About 60% of adult diets are ultraprocessed, and two-thirds of the calories kids eat in the US are ultraprocessed,” Zhang said.
“It makes me think of when we first made cars,” she said. We do find them useful, but if we use them for everything and don’t exercise, we’ll have problems. To lower the amount of ultraprocessed food people eat to a better level, we need new plans.
What you can do to eat less ultraprocessed food
It’s simple: just buy real food and cook it at home. The pros say it’s that easy. But experts also agree that it’s hard to give up the ease of ready-to-heat and ready-to-eat foods in today’s busy world. Along with that, it’s hard to resist desire because more than 70% of the food in the US is ultraprocessed.
Monteiro suggested that governments and public health agencies should think about putting warning labels on the front of packages, limiting advertising, especially to children, and not selling ultraprocessed foods in or near hospitals and schools. At the same time, minimally processed foods should be made easier to get and cheaper.
Between then and now, Marx and Lane gave the following advice:
1) Read and compare labels, and try to pick foods that have been prepared less. Like, instead of spiced yogurt, try plain yogurt with fruit added to it.
2) What you leave out is just as important as what you add. Pay attention to what you can eat more of, like fresh, frozen, or canned fruits, veggies, beans, and other legumes.
3) Watch out for drinks. Beverages with added sugar are not good for you. Change them for water.
4) Instead of fast food chains, eat at neighborhood restaurants and coffee shops when you go out to eat. Food places in your area are less likely to make ultraprocessed foods.