Extract taken from:
If your mind wanders or you have memory lapses here and there, you may need more zinc and iron in your diet. A lot of research has linked decreased iron and zinc levels with poorer mental performance in children, but new studies on adults suggest these same elements help keep grown-ups’ minds sharp as well. Marginally low iron reserves reduced adults’ ability to concentrate, and lower levels of zinc slowed test participants’ ability to recall words.
What to eat: Good sources of iron include red meat (preferably lean), oysters, fortified cereals, pumpkin seeds, pistachios, tofu, and blackstrap molasses. (For better iron absorption from plant foods, pair them with good sources of vitamin C, such as orange juice.) For zinc, choose red meats, oysters, dark-meat poultry, pork, pumpkin seeds, soy nuts, and wheat germ.