“The study results suggest that people who ate one serving of green, leafy vegetables had a slower rate of decline on tests of memory and thinking skills than people who rarely or never ate them. The study results also suggest that older adults who ate at least one serving of leafy green vegetables showed an equivalent of being 11 years younger cognitively.”
Mas, from 2015: Lots of leafy greens might shield aging brains, study finds
Nutrition questions? Go see Dr. Greger — he’s got you covered.