Aluminum cookware has been around for a long time, but in the 1960s, safety concerns began to be raised over possible leaching of aluminum into food. The popularity of aluminum pots and pans is mainly based on two things: They are cheap, and they conduct heat very effectively. However, many suitable alternatives soon surfaced, such as stainless steel, porcelain, glass and iron.
The only poison that can leach into food by cooking with aluminum is the aluminum itself. The reason this became a concern is that large amounts of the material have been found in the brains of Alzheimer's patients, which proves that aluminum crosses the blood/brain barrier. This does not establish a causal link, which would be needed to say definitively that aluminum in the brain causes Alzheimer's disease.
The environment provides many sources of aluminum beyond cookware. It occurs naturally in soil and can be absorbed by produce grown there. In addition, aluminum is added to many consumer goods, including antacids, hemorrhoid medication and other over-the-counter medicines; baking powder; boxed cake mixes; deodorants and antiperspirants; douches; processed cheese; pickles; toothpaste; and table salts, to name just a few. In other words, it's nearly impossible to lead an aluminum-free life.
The body derives no benefits from aluminum, and in large quantities, it is harmful. The question then is one of quantity. If the food is not highly acidic or basic on the pH scale, less leaching occurs. "Leaching is most likely when the foods being cooked or stored are highly basic, like baking soda, or highly acidic, like tomato sauce, lemon juice, oranges or vinegar," according to the Tree Hugger website. In the case of tomato sauce, 3 to 6 milligrams of aluminum have been found per 100 g servings after being cooked in an aluminum pan. This is approximately 10 percent of the aluminum the average person consumes in a day.
About 99 percent of ingested aluminum is excreted by the kidneys, except in patients with renal failure, in which aluminum retention within the body is responsible for "dialysis dementia." In addition, dialysis patients often suffer from anemia and a specific form of metabolic bone disease, both due to aluminum retention.
Aluminum is on the "2007 list of top priority toxins in the United States (a list put out every year by the Agency for Toxic Substances and Disease Registry), and aluminum has been clearly identified as a toxin for the human nervous system, immune system and genetic system." Furthermore, "A study by the Australian Institute for Biomedical Research determined that over a period of seven or eight decades of drinking aluminum-treated tap water, a microgram of aluminum would accumulate in the human brain," writes Michael Brower and Warren Leon, from the Union of Concerned Scientists.
Aside from glass, stainless steel, modern enamel (which is cadmium-free) and iron, there is anodized aluminum. Anodization is a process by which aluminum is treated with a nonreactive hard coating of aluminum called aluminum oxidation, which does not leach, but it might still be prudent to avoid storing tomato sauce and other acidic substances in any aluminum vessel. Care should also be taken to discard aluminum ware that is damaged in any way, which can happen even with the anodized version.