A total of 708 participants, between 63-79 years old, were included in this study. The subjects were randomly allocated to the walnut group (30-60 g/day) or the control group (abstention from walnuts). Researchers administered a comprehensive neurocognitive test battery at the beginning of the study and after 2 years.
Thanks to the functional magnetic resonance imaging, the study results showed that walnuts might delay cognitive decline in subgroups at higher risk, such as in elderly.