With the average age of Americans increasing, the risk of Alzheimer's may also go up. In individuals aged 75 to 84, one out of five has Alzheimer's. In those older than 85, the rate is two out of five. And like heart disease, you're stuck with some risk factors like heredity. Fortunately, there are ways to keep your brain alive through better nutrition and exercise. Here's the latest research:

1. Go fish. The omega-3 fatty acids found in salmon, mackerel and halibut aren't just good for your heart. A handful of research studies suggest that the anti-inflammatory properties of fish are also beneficial in protecting the cell membranes in your brain. Aim for at least 5 oz of fatty fish (2-3 servings) per week.
2. Eat green. Researchers at Harvard found that nurses who ate the most green, leafy vegetables had slower cognitive decline than those consuming the least. Aim for three servings of raw or cooked spinach, kale, romaine and iceberg lettuce daily.
3. Avoid 'bad' fats. In two large population studies of older adults, the risk of Alzheimer's disease was doubled in those who consumed the most saturated fat compared to those who ate the least. Consumption of trans fat (found in margarine and processed foods) also increased the risk of Alzheimer's. Choose monounsaturated fat (canola, olive or peanut) over saturated fat (butter, bacon, beef, processed meats, etc).
4. Eat vitamin E-rich foods. While vitamin E supplements have not shown much benefit in preventing cognitive decline, vitamin E in foods may help. Gamma-tocopherol (found in leafy greens, nuts, whole grains and vegetable oils) has powerful anti-inflammatory properties. Snack on nuts and choose whole grains (such as whole wheat bread or bran cereal) when possible.
5. Move it or lose it. In the Harvard Nurse's Health study, participants over 70 who exercised scored higher on cognitive tests than those who didn't exercise. Regular exercise was found to help maintain memory. Go for at least 30 minutes of brisk walking daily, or most days of the week. Regular physical activity also lowers blood pressure, improves blood sugar and helps shrink your waistline.

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