I decided that my health might be worth a little time spent investigating what should and should not touch my food when it is cooked or stored. The results were sometimes surprising.

Many of us are concerned about using aluminum cookware. More than half of all cookware sold today is made of aluminum, usually coated with nonstick finishes or anodized to harden the structure and make it more scratch-resistant. Although there is no direct evidence that aluminum causes Alzheimer's disease, there is enough controversy that we seniors might prefer to avoid exposure to the metal. Anyone using uncoated aluminum pans for cooking and aluminum foil for food storage would take in about 3.5 milligrams of aluminum daily.

Contrast this to the use of over-the-counter antacid tablets, which can deliver 50 milligrams of aluminum per tablet, and buffered aspirin, which can contain about 10 to 20 milligrams of aluminum per tablet! However, consumer advocates caution that use of aluminum pans for cooking or storing any highly acidic or salty foods—for example, tomatoes, vinegar, lemon juice, rhubarb, applesauce or sauerkraut—can cause significantly more of the metal to leach into food, even to the extent of pitting the container's surface. Even using fluoridated water while cooking in aluminum can seriously increase the leaching of aluminum.

Although nonstick coatings will wear and chip with hard use, the Food and Drug Administration claims that these particles pass unchanged through your body and pose no health hazard. Note that these pans heated at high temperatures will give off fumes, but these are less toxic than those released by ordinary cooking oils. However, the products of highly heated or burned cooking oils have been found in some studies to be carcinogenic.

Stainless steel cookware has a hard, nonporous surface that seems to resist wear for years. It is usually made of iron and chromium and may contain nickel or titanium, adding to the special hardness and resistance to high temperatures. Because stainless steel does not conduct heat evenly, these pots are often made with copper or aluminum bottoms. Although the manufacturers claim there are no health hazards from leaching of these metals, they also caution against allowing acidic or salty foods to remain in them for long periods.

Consumer advocate Debra Lynn Dodd states in her book Home Safe Home that "if stainless steel cookware is scoured only once with an abrasive powder or steel wool, small amounts of highly toxic metals such as chromium or nickel may leach into every food cooked in it thereafter."

Copper cookware is an excellent conductor of heat and usually is lined with tin or stainless steel. The FDA cautions against using unlined copper because the metal is easily dissolved by some foods; in sufficient quantities this can cause nausea, vomiting and diarrhea.

Cast iron skillets have been in use for centuries. Cooking with cast iron can provide a source of iron, an important nutrient. In fact, foods cooked in unglazed cast iron may contain twice the amount of iron they would otherwise. For those who need to control the amount of iron they intake, beware.

Enamel-coated iron and steel is stain- and scratch-resistant and doesn't contain lead—except in some glazes for slow-cookers or crock-pots. However, the amount of lead that leaches into food from these pots does not exceed FDA standards. Those who prefer to avoid any lead in their food might want to buy lead-free, enamel-coated pots. Lead has not completely disappeared; although not ubiquitous, check the canned goods in your local supermarket. "Soldered cans have a top and bottom rim with a wide seam that peeks out at the edge of the label," says Debra Lynn Dodd. "A lead-free soldered can has a flat, thin, neat seam with a characteristic narrow black or blue line running down the middle."

Microwaving food adds the questionable use of various plastics. Plastic containers from prepared microwavable meals are meant for one-time use and should not be reused. Margarine tubs, whipped topping bowls and other plastic containers can warp or melt, possibly releasing harmful chemicals into food. Beware of cling films where they might melt into the food. Wax paper, oven cooking bags and parchment paper should be safe. Use glass or glass ceramic cookware that is labeled for microwave use. To check if pottery or dinnerware is microwave safe, place the empty item in the microwave alongside a cup of water in a glass measure. Microwave on high for one minute. If the dish is cool, it is safe to use.

So what's safe? Glass, cast iron, porcelain enamel-coated cast iron or stainless steel, or terra cotta (if the glaze doesn't contain lead). For instant no-stick finishes, use parchment paper in baking pans and spread liquid lecithin (in nonstick cooking sprays) in frying pans. Bon appetit!