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Studies have shown that blueberries in particular help protect the brain and may reduce the effects of age-related illnesses such as Alzheimer's disease and dementia. Aim for 1 cup of blueberries a day; they can be fresh, frozen, or freeze-dried. Pomegranates (or pomegranate juice without added sugar) are also a good source of antioxidants. Many fish, including salmon, are rich in the omega-3 essential fatty acids that are necessary for brain function. These acids also reduce inflammation. Aim for a 4-ounce serving 2 to 3 times per week. Avocados offer another source of healthy fat monounsaturated, which helps lower blood pressure and contributes to healthy blood flow. Nuts and seeds are great sources of vitamin E, which can help minimize the cognitive decline that accompanies age. Aim for 1 ounce each day of nuts or unhydrogenated nut butters. Raw or roasted doesn't matter, but be careful of salt content. Eating whole grains promotes cardiovascular health, which promotes blood flow throughout the entire body, including the brain. Aim for 1/2 cup of whole-grain cereal, 1 to 3 slices of bread, or 2 tablespoons of wheat germ each day. Beans help stabilize blood sugar (glucose), upon which the brain depends for fuel. Aim for 1/2 cup of beans every day. Aim for 2 to 3 cups per day of either hot or cold tea. The small amount of caffeine that tea contains can help enhance memory, focus and mood. Tea also contains antioxidants. Make sure the tea is loose leaf or in a tea bag: bottled or powdered teas are not effective. If you suffer from stress, you may need to reduce your caffeine intake as this can increase your anxiety/stress. Dark chocolate contains antioxidants and several natural stimulants, including caffeine, to enhance focus and concentration, and boost one's mood. Aim for 1/2 to 1 ounce (but no more than that) per day. The brain is made up of roughly 80% water; when your brain is chronically dehydrated, it does not function properly. To calculate how much water you need to drink each day, take your weight in pounds and divide it by 2. That is how much water you should drink each day, in ounces. If you weight 150 pounds, you'll need to drink 75 ounces of water each day. You may need to drink more water on days where you sweat more, for example, from exercise or hot weather. There is not enough scientific research to prove that any of the popular "brain boosting" supplements actually work. Ones that have potential include ginkgo biloba (improves blood flow), omega-3 fatty acids, Huperzine A, Acetyl-L-carnitine, vitamin E, and Asian/Panax ginseng.
Eat antioxidants. Eat healthy fats. Eat nuts and seeds. Eat whole grains. Eat beans. Drink freshly brewed tea. Eat dark chocolate. Drink enough water. Consider taking supplements.