We know that certain foods are protective of our physical health. But what you eat can also affect your ability to think and remember, especially as you get older. Can you make nutritional choices, for example, that reduce your chances of getting Alzheimer’s Disease? This intriguing possibility was addressed in a recent study.

That study, from Boston’s Brigham and Women's Hospital, found that what we eat can either help sustain our memories and reduce the chances of Alzheimer’s Disease, or it can increase our risk of diminishing mental abilities.

Six metabolites were associated with our abilities to think. Four that were sugars or derivatives of sugars dampened thinking.

Researchers identified several sets of metabolites — break-down products from the foods we eat — that seem to be associated with thinking ability. Some of them impaired cognitive performance as measured by standard test scores of the participants; others seemed to keep it sharp. Also noteworthy is the fact that the findings appear to apply to a diverse group of races and ethnicities.

Six metabolites were associated with our abilities to think. Four that were sugars or derivatives of sugars dampened thinking. While another metabolite, beta-cryptoxanthin, typically a byproduct of digesting fruit, was associated with better cognitive ability.

“It is possible that these metabolites are biomarkers of a more direct relationship between diet and cognitive function,” said lead author, Einat Granot‐Hershkovitz, in a statement.

The researchers noted that participants who followed the Mediterranean diet had higher levels of beta-cryptoxanthin and higher cognitive abilities. The Mediterranean diet also lowered the levels of the “sugar” metabolites which negatively impacted thinking.

The study was observational and so could only show a connection between diet and cognition. It could not establish a definite cause and effect relationship between these metabolites and a person’s thinking abilities. Future prospective studies will need to see if changes in diet — as seen in changing metabolite levels — can improve cognitive health.

“…[R]epeated research has shown that the Mediterranean diet is associated with better health outcomes, including cognitive health,” said Tamar Sofer, PhD, director of the Biostatistics Core Program in Sleep Medicine Epidemiology at the Brigham. “Our study further supports the importance of a healthy diet towards safeguarding cognitive function, consistent across races and ethnicities.”

The study is published in Alzheimer’s & Dementia.