Concerns with aluminum cookware come from the fact that measurable amounts of aluminum can migrate from the pot into the food. Several research studies have confirmed migration of aluminum from conventional aluminum cookware at a level of concern for our health. Aluminum is included in the 2007 list of top priority toxins in the United States (a list put out every year by the Agency for Toxic Substances & Disease Registry), and aluminum has been clearly identified as a toxin for the human nervous system (neurotoxicity), immune system (immunotoxicity), and genetic system (genotoxicity).
Anodization is a process in which chemical baths are used to prepare the surface of aluminum to receive an electrical charge that will increase the thickness of the oxide layer and make it harder, more durable, and less likely to corrode. Anodized aluminum is definitely less reactive than non-anodized aluminum and will leach less aluminum as a result, provided that the surface has not been damaged. Although it is more difficult to damage the surface of anodized versus non-anodized aluminum, its surface can still be damaged.
Although the non-stick properties of anodized aluminum have been a selling point for this cookware to consumers, most cookware in the marketplace using anodized aluminum does not feature this material on the surface that is in contact with the food; instead, they feature a specialized non-stick surface that may have potential toxicity problems much greater than anodized aluminum. Many manufacturers are taking advantage of the durability and quick heat-transfer properties of anodized aluminum by using this material on the exterior of their pots and pans, but they are leaving the non-stick tasks to another material (not anodized aluminum).
Given all of the potential health risk factors listed above-together with the environmental problems created by aluminum mining and manufacturing-I still favor stainless steel, enamel porcelain-coated pots, and certain ceramic cookware (those fired at high temperatures and without heavy metals or toxic color pigments in the glaze). Copper-bottomed pots or pots with a layer of copper in between the stainless steel are also fine. Some stainless steel cookware now comes with a layer of anodized aluminum sandwiched inside, and that cookware would also be fine from a health standpoint, even though the environmental problems with aluminum would remain.
It's important to wash all cookware carefully. For example, take care not to scour stainless steel pots too harshly when cleaning them as once the surface of the stainless steel has been damaged, the pot will leak nickel into the food that is being cooked. Stainless steel pads or brushes, for example, are too harsh in my opinion to risk using.
Inside the oven, stainless steel, tempered glass designed for oven use (for example, oven-safe Pyrex), and non-leaded ceramic are all good choices.
Rajwanshi P, Singh V, Gupta MK, et al. Leaching of aluminium for cookwares: A review. Environmental Geochemistry and Health. 1997;19(1):1-18.
Gramiccioni L, Ingrao G, Milana MR, et al. Aluminium levels in Italian diets and in selected foods from aluminium utensils. Food Additives and Contaminants. 1996; 13(7):767-774.