CNN —
We all eat them — highly processed foods like frozen pizza and ready-to-eat meals make our busy lives that much easier. Besides, they’re just plain delicious – who isn’t sensitive to hot dogs, sausages, burgers, fries, sodas, cookies, cakes, candies, donuts, and ice cream, just to name a few?
If more than 20% of your daily calorie intake comes from highly processed foods, however, you may be increasing your risk for cognitive decline, according to a new study.
This amount would equate to about 400 calories per day on a 2,000 calorie per day diet. For comparison, a small order of fries and a regular cheeseburger from McDonald’s contains a total of 530 calories.
The part of the brain involved in executive function — the ability to process information and make decisions — is particularly hit, according to the study published Monday in JAMA Neurology.
Men and women in the study who ate the most highly processed foods had a 25% faster rate of decline in executive function and a 28% faster rate of overall cognitive decline compared to those who ate the least amount of highly processed food.
“Although this is an association study, not designed to prove cause and effect, there is a number or evidence that supports the proposition that some acceleration of cognitive decline may be attributable to highly processed foods,” said Dr. David Katz , an expert in preventive medicine and lifestyle nutrition, who was not involved in the study.
“The sample size is significant and the follow-up extensive. “Although there is no evidence, this is strong enough to conclude that highly processed foods are probably bad for our brains.”
However, there was an interesting twist. If the overall diet quality was high — meaning the person also ate lots of unprocessed, whole fruits and vegetables, whole grains and healthy sources of protein — the association between highly processed foods and cognitive decline disappeared, Katz said.
“Ultra-processed foods reduce the quality of the diet, and so their concentration in the diet is an indicator of poor diet quality in most cases,” Katz said. “As informal as it seems, apparently some of the participants made it. And when diet quality was high, the observed association between highly processed foods and brain function was reduced.”
The study followed over 10,000 Brazilians for up to 10 years. Just over half of the study participants were female, white or college-educated, and the average age was 51.
At the beginning and end of the study, a cognitive test was administered, which included immediate and delayed word recall, word recognition and verbal fluency, and the participants were asked about their diet.
“In Brazil, highly processed foods make up 25% to 30% of total calorie intake. We have McDonald’s, Burger King and we eat a lot of chocolate and white bread. It’s not very different, unfortunately, from many other Western countries,” Dr. Claudia Suemoto, assistant professor in the department of geriatrics at the University of São Paulo School of Medicine, when the study abstract was released in August.
“Fifty-eight percent of the calories consumed by United States citizens, 56.8 percent of the calories consumed by British citizens and 48 percent of the calories consumed by Canadians come from highly processed foods,” Suemoto said.
Ultra-processed foods are defined as “industrial formulations of food substances (oils, fats, sugars, starches, and protein isolates) that contain little or no whole food and typically include flavors, colors, emulsifiers, and other cosmetic additives,” according to the study. .
Those in the study who ate the most highly processed foods were “more likely to be younger, female, white, have higher education and income, and were more likely to have never smoked and less likely to be current alcohol consumers,” the study found. .
In addition to impacting cognitive function, highly processed foods are already known to increase the risk of obesity, heart and circulatory problems, diabetes, cancer and a shorter lifespan.
“Ultra-processed foods in general are bad for every part of us,” said Katz, president and founder of the nonprofit True Health Initiative, a global alliance of experts dedicated to evidence-based lifestyle medicine.
Ultra-processed foods are typically high in sugar, salt and fat, which promote inflammation throughout the body, which is “perhaps the most significant threat to healthy aging in the body and brain,” said Dr. Rudy Tanzi, professor of neurology at Harvard. School of Medicine and Director of the Genetics and Aging Research Unit at Massachusetts General Hospital in Boston. He did not participate in the study.
“Meanwhile, as convenient as a quick meal, they also replace eating high-fiber foods that are important for maintaining the health and balance of the trillions of bacteria in your gut microbiome,” added Tanzi, “the which is particularly important. important for brain health and reducing the risk of age-related brain diseases such as Alzheimer’s disease.”
How can you avoid this happening to you? If you include highly processed foods in your diet, try to counter them by also eating high-quality, whole foods such as fruits, vegetables and whole grains.
“The conclusion suggested here is that highly processed foods are indeed an important ‘ingredient,’ but the exposure that should be the focus of public health efforts is the overall quality of the diet,” Katz said.
An easy way to ensure diet quality is to cook and prepare your food from scratch, Suemoto said.
“We say we don’t have time, but it really doesn’t take that much time,” Suemoto said.
“And it’s worth it because you’ll protect your heart and you’ll protect your brain from dementia or Alzheimer’s disease. That’s the message: Stop buying things that are over-processed.”
