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We all eat them – ultra-processed foods such as Frozen pizza and ready meals make our busy lives so much easier. Plus, they’re damn good—who doesn’t love hot dogs, sausages, burgers, french fries, soda, cookies, cakes, candy, donuts, ice cream, and more?
However, if more than 20 percent of your daily calorie intake is ultra-processed food, you may be at increased risk of cognitive decline, new study established.
On a 2,000-calorie-per-day diet, this amount equates to about 400 calories per day.For comparison, a small french fries and Plain Cheeseburger from McDonald’s contains 530 calories.
The part of the brain involved in executive function — the ability to process information and make decisions — was hit especially hard, according to the study published Monday in JAMA Neurology.
In fact, the study found that men and women who ate the most ultra-processed foods experienced 28 percent faster overall cognitive decline and 25 percent faster decline in executive function compared to those who ate the least ultra-processed foods.
“While this is an association study and not intended to prove cause and effect, there are numbers or elements that reinforce the proposition that the acceleration of cognitive decline may be attributable to ultra-processed foods,” said research expert David Katz, Ph.D. Say. Preventive and Lifestyle Medicine and Nutrition, who were not involved in this study.
“The sample size was large and the follow-up was extensive. While the evidence is lacking, it’s strong enough that we should conclude that ultra-processed foods may be bad for our brains.”
However, there is an interesting twist. If the overall diet is of high quality — meaning the person also eats a lot of unprocessed, whole fruits and vegetables, whole grains and healthy protein sources — there’s a link between ultra-processed foods and cognitive decline, Katz said. The association disappears.
“Ultra-processed foods reduce diet quality, so in most cases their concentration in the diet is an indicator of poor diet quality,” Katz said. “Although it may seem atypical, it is clear that some participants did. The observed association between ultra-processed foods and brain function was weakened when the diet was high in quality.”
The study was published on Monday at 2022 Alzheimer’s Association International Conference In Santiago, more than 10,000 Brazilians were followed for 10 years. More than half of the study participants were female, white, or college-educated, and the average age was 51.
Cognitive tests, including immediate and delayed word recall, word recognition and verbal fluency, were administered at the beginning and end of the study, and participants were asked about their diet.
“In Brazil, ultra-processed food is 25 to 30 percent of the total calorie intake. We have McDonald’s, Burger King, we eat a lot of chocolate and white bread. Unfortunately, it’s not that different from many other western countries, said co-author Claudia Suemoto, MD, assistant professor in the Department of Geriatrics, Faculty of Medicine, University of São Paulo.
“58 percent of calories consumed by US citizens, 56.8 percent of calories consumed by UK citizens and 48 percent of calories consumed by Canadians came from ultra-processed foods,” Suemoto said.
According to the study, ultra-processed foods are defined as “industrial formulations of food substances (oils, fats, sugars, starches, and protein isolates) with little or no natural food ingredients, often including flavorings, colours, emulsifiers, and other Cosmetic Additives”.
Study co-author Natalia Gonçalves said: “People who consumed more than 20 percent of their daily calories from processed foods had a 28 percent faster decline in overall cognitive performance and a faster decline in executive function compared to those who consumed less than 20 percent. 25 percent,” said the researcher at the Department of Pathology, Faculty of Medicine, University of São Paulo.
In addition to the impact on cognition, ultra-processed foods are known to increase obesity, heart and circulation problems, diabetes, cancer and a shorter life.
“Ultra-processed food in general is bad for every part of us,” said Katz, president and founder of the nonprofit real health initiativea global alliance of experts dedicated to evidence-based lifestyle medicine.
Ultra-processed foods are often high in sugar, salt and fat, all of which promote Systemic inflammation, which is “probably the greatest threat to healthy aging of the body and brain,” said Dr. Rudy Tanzi, professor of neurology at Harvard Medical School and director Department of Genetics and Aging Research, Massachusetts General Hospital, Boston. He was not involved in the study.
“At the same time, because of their convenience as a quick snack, they can also replace foods rich in plant fiber, which is important for maintaining the health and balance of the trillions of bacteria in the gut microbiome,” added Tanzi, ” This is especially important for brain health and reducing the risk of age-related brain diseases like Alzheimer’s disease.”
How can you prevent this from happening to you? If your diet includes ultra-processed foods, try to combat them by consuming high-quality whole foods such as fruits, vegetables, and whole grains.
“The conclusion presented here is that ultra-processed foods are indeed an important ‘ingredient,’ but it is overall diet quality that should be the focus of public health efforts,” Katz said.
An easy way to ensure a quality diet is to cook and prepare food from scratch, Suemoto says.
“People need to know that they should cook more and prepare their own food from scratch. I know. We say we don’t have time, but we don’t really need that much time,” Suemoto said.
“It’s worth it because you’re going to protect your heart and protect your brain from dementia or Alzheimer’s disease,” she adds. “Here’s the take-home message: Stop buying ultra-processed stuff.”