An ounce of prevention is worth much more than a pound of cure. A healthy dose of preventive medicine is as near as your local farmers' market. Fresh fruits and vegetables are proven winners in the fight to stave off dementia, and some research even suggests that these powerful plant foods may turn back the cognitive clock.

• Broccoli, cauliflower, and other cruciferous vegetables are great for memory.
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• Spinach and other leafy greens are among the richest sources of folate (a B vitamin) which appears to play a major role in preventing stroke, which accounts for 25 percent of dementia cases. Folate may also reduce the risk of Alzheimer's disease by helping the body break down homocysteine, an amino acid that is toxic to nerve cells.
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• Nuts are high in fat, but it's the right kind of fat.. cholesterol lowering, artery protecting, inflammation-fighting fat. Other smart choices for a healthy brain include monounsaturated oils like olive and canola, and fatty fish such as salmon, mackerel, and tuna.

• For antioxidants blueberries beat out about 50 other fresh fruits and vegetables. They also combat inflammation. That combination is powerful in the fight against Alzheimer's disease.
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• Fruit and vegetable juice are protective. A study found that older adults who drank at least three glasses of juice a week had a 75 percent lower risk of Alzheimer's disease compared to those who drank juice less than once a week.