A recent study by Tulane University suggests that the brain-boosting benefits of the Mediterranean diet might be due to changes in gut bacteria.
Published in Gut Microbes Reports, the research found that people following a Mediterranean diet had different gut bacteria patterns than those eating a Western diet. These changes were linked to improved memory and cognitive performance.
“We know that diet affects brain function, but this study looks at how that happens,” said lead author Dr. Rebecca Solch-Ottaiano from Tulane’s Clinical Neuroscience Research Center. “Our findings suggest that what we eat can influence cognitive performance by changing the gut microbiome.”
In the study, rats were fed a Mediterranean-style diet rich in olive oil, fish, and fibre for 14 weeks. This led to increases in beneficial gut bacteria and decreases in harmful bacteria, compared to rats eating a Western diet high in saturated fats. These bacterial changes were linked to better performance on memory tests.
Specifically, higher levels of certain bacteria were associated with better cognitive performance, while increased levels of others were linked to poorer memory function.
The rats on the Mediterranean diet also showed better cognitive flexibility (the ability to adapt to new information) and improved working memory compared to those on the Western diet. They also had lower levels of “bad” LDL cholesterol.
This study is the first to compare the effects of Mediterranean and Western diets on gut bacteria and cognitive function in a rodent model. The researchers used young rats to model the effects of diet during a critical developmental period, with diets reflecting human consumption. The Mediterranean diet clearly benefits memory, cognitive flexibility, and gut health.
“Our findings suggest that the Mediterranean diet could potentially improve academic performance in adolescents and work performance in young adults,” said Dr. Demetrius M. Maraganore, co-author of the study. “Although these results are based on animal models, they are consistent with human studies linking the Mediterranean diet to better memory and reduced dementia risk.”
The researchers emphasize the need for more extensive human studies to confirm these effects and better understand the complex relationship between diet, gut bacteria, and brain function.
Key Components of the Mediterranean Diet:
- Olive oil as the primary fat source
- Plenty of vegetables, fruits, and whole grains
- Fish and lean proteins
- Limited red meat and saturated fats
- High fiber intake from various plant sources