Dietary and nutraceutical plant chemicals relevant to cognitive functions are diverse in structure; examples are shown that occur in turmeric (curcumin), grapes and red wine (resveratrol), blueberries (cyanidin), tea (epigallocatechin gallate), citrus fruit (nobiletin), coffee (caffeine and trigonelline), saffron (crocetin) and sage and rosemary (rosmarinic acid, carnosic acid, α‐pinene, and 1,8‐cineole)