Eating nuts a few times a week may help preserve cognitive function through a healthier gut microbiome
A new study published in Age and Ageing suggests that eating 3 to 7 servings of nuts per week may support cognitive health in older adults at risk of decline.
This prospective study followed 747 older adults (aged 55–75 years), all with overweight or metabolic syndrome, conditions linked to higher dementia risk. Researchers assessed participants’ baseline nut consumption using a detailed food questionnaire and profiled their baseline gut microbiota composition on the basis of stool samples. They then tracked the participants’ cognitive function over time using a comprehensive set of neuropsychological tests to explore potential links between nut intake, gut health, and brain function.
Over a six-year period, participants who ate 3 to 7 servings of nuts per week experienced significantly slower declines in global cognitive function compared to those who ate nuts less than once per week. Importantly, this cognitive benefit was accompanied by a more diverse gut microbiota. The study found that participants with moderate nut intake had higher microbial diversity and greater abundance of bacteria associated with the production of short-chain fatty acids. One such bacterium, Lachnospiraceae UCG-004, was also linked to better cognitive performance over time, highlighting a possible role for the gut-brain axis in mediating the effects of nut consumption.
These findings build on earlier research linking nut-rich diets to improved brain function and offer new evidence that gut health may be a key pathway. The results underscore the potential of moderate nut intake as a simple, diet-based strategy to support healthy aging.
Ni, J., Nishi, S. K., Babio, N., Belzer, C., Konstati, P., Vioque, J., Corella, D., Castañer, O., Vidal, J., Moreno-Indias, I., Torres-Collado, L., Guillem-Saiz, P., Fitó, M., Ruiz-Canela, M., Hernández-Cacho, A., Tinahones, F. J., & Salas-Salvadó, J. (2025). Nut consumption, gut microbiota, and cognitive function: findings from a prospective study in older adults at risk of cognitive decline. Age and Ageing, 54(7), afaf208.