The brain's oxygen needs are not as simple as getting enough oxygen. Maintaining healthy oxygen levels in the brain is a matter of two things: providing enough beneficial oxygen and combating a different, potentially harmful type of oxygen called free radicals. In both efforts, nutrition can help.
Free Radicals & Antioxidants
Free radicals are actually a type of oxygen that is extremely unstable and can damage the cells of the body, including brain cells. Antioxidants help keep free radicals under control by preventing them from attacking other cells of the body or brain. Without the support of antioxidants, free radicals can cause cognitive decline and possibly lead to stroke and neurodegenerative diseases such as Parkinson's and Alzheimer's disease. Antioxidants also help protect the red blood cells that carry oxygen to the brain.
Fruits & Vegetables
Fruits and vegetables in general are high in antioxidants. In a 2001 annual meeting of food scientists at the Institute of Food Technologists, citrus fruits such as oranges and lemons and cruciferous vegetables including broccoli and cabbage were associated with a reduced risk of stroke. Blue and purple fruits and vegetables, like blueberries and eggplant, are high in a type of antioxidant called proanthocyanidins, considered particularly beneficial to the brain. These proanthocyanidins are able to cross the blood-brain barrier and can therefore protect against both water-soluble and fat-soluble free radicals, preventing oxidative damage to both the walls and interiors of the cells. They are also the first antioxidants to attack free radicals, leaving other antioxidant vitamins, such as C and E, free to perform their normal metabolic functions.
Vitamin E-Rich Foods
Vitamin E, contained in high concentrations in nuts, seeds and soybeans, helps supply the brain with beneficial oxygen in a number of ways. As the main fat-soluble antioxidant the body contains, it plays a leading role in preventing oxidative damage to the brain. It also helps break down blood clots, helping restore the free flow of blood and the oxygen it carries to the brain. Vitamin E also supports the strength and functioning of red blood cells, the part of blood responsible for carrying oxygen to the cells of the brain and body. Other significant food sources of vitamin E include brown rice, free-range eggs, oats and fresh wheat germ. Lesser amounts can also be found in Brussels sprouts, broccoli and dark leafy green vegetables.
The body requires iron to produce hemoglobin, the red blood cell protein responsible for transporting oxygen to the cells and tissues of the body and brain. Heme iron -- the form of iron most easily absorbed and utilized by your body -- is found mostly in meat, fish and poultry. You can find nonheme iron in plant-based foods, such as spinach and lentils. While your body can't absorb nonheme iron as easily as heme iron, you can still use it to make hemoglobin.