Lead is bad for you, but many metals are vital to life. Some of these "good metals" are listed below. Cells usually need them in just miniscule amounts.
[Ca] Calcium. Did you know that this essential component of bones and teeth is a metal? In our bodies, calcium is abundant in bones and is critical for proper muscle and nerve function. Good dietary sources include dairy products, broccoli, figs, and sardines.
[Fe] Iron. Iron is not only found in skyscraper steel and frying pans, it is also in the bloodstream. Iron from foods like meat, beans, and spinach helps carry oxygen throughout our bodies.
[Cu] Copper. The metal copper is found in old pennies, high-quality plumbing, and electrical wires. It's also in lobster, crabs, beans, and nuts. In our bodies, copper helps mop up dangerous "free radicals," highly reactive chemicals that have been linked to an increased risk of cancer and heart disease.
[Mg] Magnesium. Magnesium is a metal used in flares and fireworks. Our bodies need magnesium for strong bones and teeth, as well as for muscle contraction and relaxation. Food sources include vegetables, especially dark green, leafy ones.
[Zn] Zinc. This metal is present in a range of household products, from batteries to cosmetics. In our bodies, many proteins need one or two zinc atoms to fold into the right shape. Zinc is important for controlling gene activity and regulating hormones. Good dietary sources include oysters, chickpeas, whole grains, and nuts.
[Co] Cobalt. Mixed with other metals, cobalt is used in jet engines. It also gives a brilliant blue color to pottery, glass, and tiles. Cobalt forms the core of vitamin B12 and is important in the body for making red blood cells. This metal is found in meat, dairy products, and leafy green vegetables.
[Mn] Manganese. This metal helps to give Sacajawea dollar coins their shiny, golden luster and amethysts their purple hue. In our cells, it helps break down fats, carbohydrates, and proteins to convert food into energy. Manganese is present in whole grains and cereal products.—K.J.