At the end of 2016, Australian researchers published a study in Journal of the Australasian College of Nutritional and Environmental Medicine showing a connection between the food we eat and the size of our hippocampus.
The hippocampus is the part of our brain that plays important roles in memory (short-term, long-term, and spatial). In Alzheimer’s disease, the hippocampus is one of the first regions to suffer damage.
The researchers studied 255 men between the ages of 60 and 64 years. Each participant completed a food frequency questionnaire, had an MRI scan done, then 4 years later, had a second MRI scan done.
After analyzing the hippocampus size of each participant in both scans and comparing that with dietary intake, the researchers discovered that those who ate a typical Western diet (lower amounts of nutrient-dense food and higher amounts of unhealthy food) ended up having lower volume in the left hippocampus.
The reverse was also true: those who ate better, had larger hippocampal volume. In fact, the connection was pretty specific.
Every one standard deviation increase in healthy ‘prudent’ dietary pattern was associated with a 45.7 mm3 larger left hippocampal volume, while higher consumption of an unhealthy ‘western’ dietary pattern was (independently) associated with a 52.6 mm3 smaller left hippocampal volume.
And while the study didn’t conclude that diet directly caused the difference in hippocampal volume, if the relationship is causal, it shows how much more important it is for us to have a healthy diet, particularly as we age.