Purpose: To examine older adults' perceptions of the link between physical activity (PA) and nutrition to the maintenance of cognitive health. Design and Methods: Forty-two focus groups (FGs) were conducted with 396 ethnically diverse (White, African American, American Indian, Chinese, Vietnamese, and Hispanic) community-dwelling older adults. FGs were audio recorded, transcribed verbatim, and coded using a constant comparison method. Responses pertaining to PA and nutrition were analyzed. Results: Participants noted a positive link between both PA and dietary practices and brain health, although some participants voiced skepticism regarding diet. Walking was most frequently cited as a recommended PA, but participants did not know the recommended frequency, duration, and intensity. Limiting portion sizes; preparing foods in healthier ways; eating more fish, fruits, vegetables, low-fat foods, and chicken; and eating less red meat and chicken with the skin were associated with brain health. Multiple dietary supplements were also discussed. More racial/ethnic differences were noted for PA than for diet. Implications: Interventions and media campaigns may benefit from explicitly linking PA and dietary habits with brain health and helping older adults understand that cardiovascular risk factors are also dementia risk factors. Emphasizing the total diet (vs. specific nutrients) and providing clear messages regarding the frequency, duration, and intensity of recommended PA would also be useful.