Numerous epidemiologic studies suggest that dietary consumption of fish or of ω-3 fatty acids (the putative “active ingredient” in fish) may reduce the risk of late-life dementia including Alzheimer disease (AD). However, clinical trials have failed to demonstrate disease-modifying effects in mild to moderate AD,1,2 diminishing enthusiasm for ω-3s for brain health during aging. A study in this issue of JAMA Neurology by Yassine et al3 revisits this topic with a clinical study aimed at testing the hypothesis that the ω-3 fatty acid docosahexaenoic acid (DHA) has clinically relevant “antiamyloid” effects in the aging brain.