"Vitamin B12 has a number of roles including helping in the formation of myelin," Sahelian says. Myelin forms layers or a sheath around the nerve fibers and acts as insulation. Sahelian points out that B12 is mainly found in meats (beef, pork, lamb, veal, fish, and poultry), and an as result, vegetarians may be deficient. This deficiency could lead to nerve damage, memory loss, low moods, and mental slowness. His advice? Shoot for between 3 and 100 micrograms a day.
It worked for nutritionist Molly Kimball's grandmother. "Sometimes as people age, they have impaired absorption of B12," says Kimball, a nutritionist at the Ochsner Clinic's Elmwood Fitness Center in New Orleans. In fact, B12 deficiency can present as similar to Alzheimer's disease, she says. "My grandmother couldn't make sense until her doctor supplemented her B12," she tells WebMD.
Filling Up on Folate
Folic acid or folate is another important B vitamin for the brain, says Sahelian. "Getting adequate folate can make one a little more alert, and improve memory and focus." It helps lower blood levels of the amino acid homocysteine that is known to damage brain cells, he explains. It's found in abundant supply in many foods including beans, fruits, green leafy vegetables, lentils, and whole-wheat cereals. Shoot for 400 micrograms a day, he says.
Stirring Up Serotonin With B6
Vitamin B6 helps convert 5-hydroxy-tryptophan (5HTP) in into the mood chemical serotonin and it also helps in making dopamine. "These are big mood and alertness chemicals," he says. Aim for roughly 2 to 10 milligrams a day if you supplement. B6-rich foods include bell peppers, cranberries, turnip greens, cauliflower, garlic, tuna, mustard greens, and kale.
Magnesium is an important brain nutrient because it protects the brain from neurotoxins," says City Island, N.Y.-based Carolyn Dean, ND, MD, author of The Miracle of Magnesium. "Some enlightened surgeons give extra magnesium to their patients before and during surgery, especially brain surgery, for this reason," she tells WebMD. The dosage for protecting the brain in general is 300 milligrams one to three times a day. According to Dean, nuts, seeds, dark leafy greens, and whole grains have magnesium, but most other foods have little, she says. "Cooked and processed foods also lose a lot of magnesium making it a very deficient mineral."