Consistent consumption of highly processed foods can lead to cognitive decline: study

Throwing a frozen dinner into the microwave might be efficient in the moment, but it comes with a price, a new study indicates.

It might wreck your brain.

Overconsumption of processed foods has been blamed for a host of ills, and now cognitive decline can be added to the list. A daily diet consisting of more than 20% junk can jump-start cognitive decline, said the authors of a study presented Monday at the 2022 Alzheimer’s Association International Conference in San Diego.

That mouth-watering array of sauces, soups, frozen pizza, fries, sausages, burgers, hot dogs, processed pastries, cake, ice cream and candy that we love to chow down on could kill us prematurely — or at least compromise our brains.

Processed foods (Shutterstock/)

As if an increased risk of obesity, vascular problems, diabetes and cancer weren’t enough, the study found a correlation between high consumption of processed foods and impairment of a brain’s executive functioning — the region that processes information and makes decisions.

More than 10,000 people were studied over 10 years in Brazil, where ultraprocessed foods comprise 25% to 30% of total caloric intake. Before and after the study, the middle-aged and older participants were given cognitive tests and were asked about their diet.

Industrially made foods that contain oils, fats, sugars, starch, protein isolates and additives like flavorings, colorings, emulsifiers and other substances were included in the dirty definition.

At the end of the study, men and women eating the highest amount of ultraprocessed foods showed a 28% faster rate of global cognitive decline and a 25% faster rate of executive function decline when compared to people who ate the least amount of overly processed food.

“Independent of the amount of calories, independent of the amount of healthy food that you try to eat, the ultra-processed food is not good for your cognition,” said study coauthor Dr. Claudia Suemoto, an assistant professor in the division of geriatrics at the University of São Paulo Medical School, to NBC News. “I know that sometimes it’s easier to open a package and throw it in the microwave, but in the long run it’s going to cost you some years of life.”

Researchers not involved in the study said its results tracked with other findings.

“While in need of further study and replication, the new results are quite compelling and emphasize the critical role for proper nutrition in preserving and promoting brain health and reducing risk for brain diseases as we get older,” Rudy Tanzi, professor of neurology at Harvard Medical School and director of the genetics and aging research unit at Massachusetts General Hospital in Boston, and not part of the study, told CNN.

“The data is incredibly strong that foods that are not part of the Mediterranean diet — foods high in fats and sugar, and now we can add to this list foods that are highly processed — absolutely, positively do contribute to one’s risk of cognitive decline and ultimately dementia,” Andrew Budson, a Boston University neurology professor who was not involved in the research, told NBC News.

At the same time, it is a correlation, not a proof of cause and effect, an Alzheimer’s expert noted.

“An increase in the availability and consumption of fast, processed and ultra-processed foods is due to a number of socioeconomic factors, including low access to healthy foods, less time to prepare foods from scratch and inability to afford whole food options,” Percy Griffin, director of scientific engagement for the Alzheimer’s Association, said in a statement obtained by NBC News. “It’s troubling but not surprising to see new data suggesting these foods can significantly accelerate cognitive decline.”