Consumption of highly processed diet can lead to memory deficits and rapid memory decline in the aging population has a greater likelihood of progressing into neurodegenerative diseases such as Alzheimer’s disease.
The researchers found that four weeks on a diet of highly processed food led to a strong inflammatory response in the brains of aging rats that was accompanied by behavioral signs of memory loss.
The journal Brain, Behavior, and Immunity published the study. For the study, the researchers used the diet mimicked ready-to-eat human foods that are often packaged for long shelf lives, such as potato chips and other snacks, frozen entrees like pasta dishes and pizzas, and deli meats containing preservatives.
A BIT ALARMING
They also found that that supplementing the processed diet with the omega-3 fatty acid DHA prevented memory problems and reduced the inflammatory effects almost entirely in older rats. Neuro-inflammation and cognitive problems were not detected in young adult rats that ate the processed diet.
Noting that the results were a little bit alarming, senior study author Ruth Barrientos (Ohio State University Institute for Behavioral Medicine Research) said that the findings showed that consumption of a processed diet can produce significant and abrupt memory deficits. This also cautions the people from limiting processed foods and increase consumption of foods that are rich in the omega-3 fatty acid DHA to either prevent or slow that progression.
THE STUDY
The research team randomly assigned 3-month-old and 24-month-old male rats to their normal chow (32% calories from protein, 54% from wheat-based complex carbs and 14% from fat), a highly processed diet (19.6% of calories from protein, 63.3% from refined carbs — cornstarch, maltodextrin and sucrose — and 17.1% from fat), or the same processed diet supplemented with DHA.
Activation of genes linked to a powerful pro-inflammatory protein and other markers of inflammation was significantly elevated in the hippocampus and amygdala of the older rats that ate the processed diet alone compared to young rats on any diet and aged rats that ate the DHA-supplemented processed food.
The older rats on the processed diet also showed signs of memory loss in behavioral experiments that weren’t evident in the young rats. They forgot having spent time in an unfamiliar space within a few days, a sign of problems with contextual memory in the hippocampus, and did not display anticipatory fear behavior to a danger cue, which suggested there were abnormalities in the amygdala.
National Institute on Aging, the National Institute of Dental and Craniofacial Research, and the Ohio Agricultural Research and Development Center supported the research. Co-authors include Michael Butler, Nicholas Deems, Stephanie Muscat and Martha Belury from Ohio State and Christopher Butt of Inotiv Inc. in Boulder, Colorado.
