Gaby
A new study by neurobiologists at the University of Southern California (USC) found that a diet high in fats and sugars can lead to irreversible memory impairments.
The USC team reached this conclusion after experiments on laboratory rats that were fed those diets from an early age. The researchers suspect a diet rich in simple sugars and saturated fats damages acetylcholine — a key neurotransmitter linked to memory.
“Not only in this study, but also in some of our previous work, we have seen that a diet of unhealthy foods causes memory impairments that are untreatable,” said co-author Scott Kanoski.
How the Study Was Conducted
The researchers worked with two groups of rats aged between 26 and 56 days. This developmental period corresponds to human adolescence, when many brain functions are still forming.
One group of rodents was fed a diet high in fats and sugars, while the other group was given healthier food, as reported by Science Alert.
In memory-recall tests, the rats on the high-fat, high-sugar diet were unable to identify new objects they had explored just a few days earlier. That failure did not occur in the control group. Worse, the memory problems persisted even after the rats were switched to a healthy diet for 30 days (a period corresponding to adulthood for the rodents).
What Else the Researchers Discovered
Neurobiologists also found that the rats consuming unhealthy food had reduced levels of a protein that transports acetylcholine to the hippocampus — the part of the brain that helps consolidate memories and spatial information.
Further experiments showed this protein decrease disrupted acetylcholine signaling, and the animals struggled with memory tasks.
“Acetylcholine signaling helps encode and remember events, akin to ‘episodic memory’ in humans, which allows us to recall events from our past,” explained lead author Anna Hays. “It seems that this signaling does not manifest in animals raised on a fatty and sugary diet.”
The study’s findings were published in the journal Brain, Behavior and Immunity.
What Other Scientists Are Saying
Other recent studies have linked diets high in processed foods to a greater risk of developing Alzheimer’s disease. Researchers have also connected unhealthy diets to a loss of appetite control. And obesity may impair the brain’s ability to register satiety.
The takeaway from these studies is simple: foods that are common in Western diets can be harmful to brain health. And that’s food for thought.
