A study involving 110 lean and healthy students (aged 20-23) found that those randomly assigned to a high energy western-style diet for a week performed worse on a memory test compared to those who ate their normal healthy diet. Moreover, those on the unhealthy diet then showed a greater tendency to eat more sugary foods.
The students at the beginning and end of the study were given breakfast in the lab. Before and after the meal, they completed word memory tests and scored a range of high-sugar breakfast foods according to how much they wanted and then liked the foods on eating them.
The more desirable people found the sugary food when full, following the western-style diet, the more impaired they were on the cognitive test. It’s suggested that both reflect impairment in hippocampal function.
Reference:
Stevenson, R. J., Francis, H. M., Attuquayefio, T., Gupta, D., Yeomans, M. R., Oaten, M. J., & Davidson, T. (n.d.). Hippocampal-dependent appetitive control is impaired by experimental exposure to a Western-style diet. Royal Society Open Science, 7(2), 191338. https://doi.org/10.1098/rsos.191338
