Granted, no one should be surprised by a study that suggests that McDonald’s is bad for your health, but occasionally a study (or a movie) comes along that shocks even us: in this case, a study suggesting that fast food purveyors are not only scrambling your eggs, but also potentially scrambling your brain.
A new study of rats from the University of North Carolina has found that consuming a fast-food like diet for just four days could make neurons in the hippocampus overactive and disrupt the ability of the brain to receive glucose, thereby interfering with memory functions as a result. The findings suggest that memory is more vulnerable to poor nutrition than previously thought, with changes appearing well before weight gain sets in.
We were a little startled by the speed of the impact, and so were the researchers. “We knew that diet and metabolism could affect brain health, but we didn't expect to find such a specific and vulnerable group of brain cells, CCK interneurons in the hippocampus, that were directly disrupted by short-term high-fat diet exposure," said Juan Song, a member of the UNC Neuroscience Center and lead researcher on the project. "What surprised us most was how quickly these cells changed their activity in response to reduced glucose availability, and how this shift alone was enough to impair memory."
The study did reveal a possible way to reverse the damage. When researchers restored glucose levels in the brain - or used intermittent fasting to regulate energy use - the neurons calmed down and memory performance improved. All in all, the study suggests that memory circuits are highly sensitive to diet - and a high-fat, saturated-fat–rich diet may increase the risk of neurodegenerative diseases like dementia and Alzheimer’s.