Adults who consumed 20% or more of their daily calories from ultra-processed foods (UPFs) showed a 28% faster rate of global cognitive decline over eight years, according to Natalia Gomes Gonçalves, PhD, of the University of São Paulo Medical School in Brazil, and co-authors.
MedPage Today’s recent article entitled “Cognitive Decline Tied to Midlife Diet” reports that the researchers also showed a 25% faster rate in executive function decline.
“Intact cognitive function is key to successful aging,” they wrote in JAMA Neurology. “Therefore, despite the small effect size of the association between UPF consumption and cognitive decline, our findings are meaningful to cognitive health.”
The results were similar to findings published earlier this year that linked ultra-processed foods with dementia risk. Notably, risk was projected in that study to drop dramatically when replacing junk food with unprocessed or minimally processed foods.
“Middle age is an important period of life to adopt preventive measures through lifestyle changes, since the choices we make at this age will influence our older years,” Gomes Gonçalves said in an email to MedPage Today.
“This does not mean that older adults will not have benefits if they adopt a healthier lifestyle,” she added. “Research has shown over and over again that we benefit from healthy choices at any age.”
A diet of 20% or more of ultra-processed foods is common, she noted. “Considering a person who eats a total of 2,000 kcal a day, 20% of daily calories from ultra-processed foods are about two 1.5-ounce Kit Kat bars, or five slices of bread, or about a third of an 8.5-ounce package of chips,” Gomes Gonçalves wrote. In the U.S., 58% of daily calories come from ultra-processed foods. In the U.K. and Canada, that figure is 47-48%; in Brazil, it’s 30%.
Gomes Gonçalves and colleagues analyzed ultra-processed food consumption at baseline and subsequent cognitive decline among 10,775 people in the Brazilian Longitudinal Study of Adult Health. The participants were public servants ages 35 to 74 recruited in six Brazilian cities from 2008 to 2019.
Cognitive evaluations included immediate and delayed word recall, word recognition, phonemic and semantic verbal fluency tests, and the Trail-Making Test part B, which were conducted over a median follow-up of eight years. Individuals were tested up to three times every four years.
Age altered the effect between ultra-processed foods and cognitive function. People younger than 60 who ate 20% or more of their daily calories as ultra-processed foods showed a quicker global cognition decline than their same-age counterparts who consumed less junk food.
“The interesting thing about the NOVA classification system is that it classifies foods based on the industrial processing they go through,” Gomes Gonçalves observed. “To make healthier choices, one can dedicate more time to cooking meals from scratch at home.”
Reference: MedPage Today (Dec. 5, 2022) “Cognitive Decline Tied to Midlife Diet”
