As life expectancy rises worldwide, so does the prevalence of dementia. Consequently, there is a great need for knowledge regarding preventive measures. Nutritional intake is likely to influence cognitive health, but the specific role of different food items remains unclear. Two large prospective studies previously investigated the relation between several types of vegetables and cognitive decline.¹·² Both studies showed an association between green leafy vegetables (spinach, kale, collards and lettuce) and a slower rate of cognitive decline. The research discussed in this article aimed to identify the individual nutrients that may contribute to the underlying protective mechanisms of green leafy vegetables.