Life is about choices, and selecting the right nutrients plays a key role in maintaining a healthy body and brain. In general terms, you want to follow a diet rich in fruits and veggies and other unprocessed foods. Eating this way will improve blood flow and mental sharpness, and can reduce your risk for stroke, neurodegenerative diseases such as Alzheimer's and dementia, depression, schizophrenia, mood disorders and even Parkinson's.