We all understand the importance of choosing healthy food for our families, but much of our efforts can be undermined if we’re preparing it in certain kinds of cookware. Chemicals, metals, and glazes used in manufacturing cookware can easily leach harmful toxins into our food and put our health at risk. Understanding just a few simple points about what to look for in cookware, as well as what to avoid, can help you make better choices so you can cook without concern.
Solid aluminum cookware has been used for generations because of its excellent ability to conduct heat. You can recognize aluminum cookware because it has a dull, pale gray appearance and it’s very lightweight; even a large pot will be easy to carry with one hand. The problem with aluminum cookware, however, is that research shows that when heated, it leaches trace amounts of aluminum into food. This is a very serious concern because aluminum, like all heavy metals, is a neurotoxin, and accumulation over time can cause harm to the brain and nervous system. Acidic ingredients like tomatoes, tomato sauce, citrus juices, and vinegar also react with the aluminum surface, making it easier for the metal to leach into food. This has even been shown to happen when aluminum foil comes into contact with acidic foods, such as covering the top of lasagna.
What has become more common today is cookware made from anodized aluminum. During anodization, cookware made from aluminum is exposed to a polymer infusion process that causes the metal to form a thick, dark gray layer of aluminum oxide on the exterior that makes the cookware considerably heavier. Because of the polymer infusion, anodized cookware has a non-stick surface. Manufacturers claim that the aluminum in anodized cookware does not leach into food because it is contained within the hard oxide coating. Because no independent tests have shown this to be true and the risks of aluminum toxicity are so great, I recommend that all aluminum cookware of any kind be avoided, this includes disposable aluminum pie pans and those turkey baking tubs that show up in grocery stores every year at Thanksgiving. You’ll also want to avoid cooking anything inside aluminum foil, including potatoes. (Yes, you can make a great baked potato without wrapping it in aluminum.)
Get rid of your non-stick cookware. Don’t panic. There are other ways to prevent food from sticking to cookware that aren’t harmful to your health and work just as well. Coconut oil is a great choice, especially for stainless steel frying pans or for greasing baking dishes.
The original non-stick coating, Teflon, was created by DuPont in 1946 and has since branched off into similar non-stick surfaces by other names such as Silverstone, Tefal, Anolon, Circulon, and others. The main problem with Teflon is that it’s made with a chemical known as perfluorooctanoic acid (PFOA) or C8 in the manufacturing world. When cookware with Teflon is heated above 500oF, it releases PFOA fumes into the air. PFOA, just one chemical in a family of perfluorinated chemicals or PFCs, accumulates in the body and has been shown to cause cancer, liver damage, and death in animal exposure testing. It’s also found in the inner bag lining of microwave popcorn, Stain Master carpet fibers, and many other products. The Environmental Protection Agency has created a voluntary program to phase out the use of PFOA in consumer products, in which DuPont has agreed to participate, and asked the eight corporations that make the chemical to stop. In the meantime, DuPont has since been ordered to pay millions of dollars to three cancer patients in West Virginia and Southern Ohio, after a jury found the company had intentionally dumped PFOA into the Ohio River, contaminating the water supply of surrounding communities. In total, DuPont faces 3,500 additional lawsuits from local residents.
The Cast Iron Question
People have been using cast iron cookware for hundreds of years, and although it’s very heavy to handle, it’s actually quite affordable. The problem lies in the fact that any food cooked in cast iron cookware takes up trace amounts of iron. This is especially the case with tomato-based, citrus, vinegar, or other acidic ingredients. If you have a condition such as hemochromatosis, where the body accumulates excess iron instead of excreting it, you need to avoid cast iron cookware. While it may not pose a danger to the rest of us, it’s important to understand that high levels of stored iron in the body is one of the strongest indicators of carotid artery disease (even more so than cholesterol), as well as heart disease and cancer.
Cast iron cookware also needs to be “seasoned” by the owner, a process where flaxseed oil is rubbed into the entire surface — not just the cooking surface — and baked in the oven for an hour. The heat causes the flaxseed oil to polymerize or solidify among the iron, creating a natural, non-stick surface. The best results are achieved if the cookware is seasoned at least three times. Pre-seasoned cast iron cookware is widely available, but it’s almost entirely seasoned with soybean oil, which is genetically modified and can cause thyroid problems, so it should be avoided.
Cast iron cookware should never be cleaned with soap to preserve the seasoned surface. Water and a clean cloth are enough. Wipe thoroughly to avoid rusting. If rust does appear, remove with coarse salt and water. You can find more detailed instructions on care and seasoning for cast iron cookware online.
Cast iron cookware with an enamel surface is available. While the food does not make contact with the iron, there have been reports that the enamel contains toxic metals like lead and cadmium, so be sure to do your research if considering purchasing it.
Carbon Steel Clarity
This cookware is seasoned and cared for in exactly the same way as cast iron, except that it isn’t nearly as heavy to handle. Avoid cooking acidic dishes containing tomatoes, citrus, or vinegar in both cast iron and carbon steel, as the food can taste slightly metallic afterward. Enameled versions are also available, but be careful to research cookware makers for the presence of lead or cadmium in their manufacturing process.
Stainless Steel Stats
As the most common cookware used today, stainless steel is the result of chromium being added to steel, an alloy of carbon and iron. Often nickel — and sometimes molybdenum — are added to prevent pitting and damage from corrosion. Because stainless steel is a poor conductor of heat, nearly all cookware will have a base added to the exterior of the bottom that contains either an aluminum or copper core encased in more stainless steel. Copper and aluminum are excellent conductors of heat, and being encased in a stainless steel core on the outside of the cookware at the bottom prevents their toxic properties from leaching into food. Some stainless steel cookware may even have an exterior copper clad bottom.
The most common type of stainless steel cookware is the 18/10 gauge, meaning that its construction includes 18% chromium and 10% nickel. The 18 designation system, however, has now been replaced by a 300 rating series where 316 is the same as the old 18/10 rating. Although generally safe, there has been some concern about nickel and chromium leaching into food, particularly due to acidic ingredients. A 2013 study published in the Journal of Agriculture and Food Chemistry showed that the risk increases with acidic dishes that cook for at least two hours or more. New cookware will leach the most, then level off after the sixth usage. You can purchase stainless steel cookware that does not contain any nickel. Under the old system, it was classified as 18/0. The downside is that it will be more prone to pitting, damage, and corrosion, so it won’t last as long, but the upside is that it will cost a lot less.
An easy way to tell if stainless steel contains nickel is to use a magnet. Stainless steel is magnetic before nickel is added. If the magnet sticks to the pot or pan, you can be sure it contains no nickel, but if the magnet fails to attach, then it does contain nickel. Even so, all stainless steel will still contain chromium. Perhaps the best thing to do to avoid leaching is to not cook acidic or tomato-based dishes in stainless steel and opt for enamel-coated carbon steel or enamel-coated cast iron for those foods instead.
Wary about Ceramic Ware
Glazed earthenware and ceramic ware are excellent choices for baking. Be careful, however, as the glaze used in some brands (especially if it’s made in China or Mexico) has been found to contain lead and cadmium. Always read the manufacturer’s labels for pledges of quality construction. If you can’t find a lead-free, cadmium-free commitment in the manufacturer’s literature, then absolutely call the company and inquire.
No Guessing with Glassware
The hand-down best choice for all bakeware is glassware. There are no metals or glazes to worry about. Be sure to use glassware for your loaf pans, pie pans, casserole dishes, 9×13, and 8×8 pans, as well. Even consider replacing some of your stainless steel or ceramic mixing bowls with clear glass bowls. Pyrex and Anchor Hocking both have an excellent line of quality products.
Putting it Together
In addition to glass bakeware, to finish filling out the most efficient and safest set of kitchenware, you might also want to consider enamel-coated, carbon steel baking sheets and roasting pans (Granite Ware), as well as frying pans, because glassware isn’t made for the stovetop. You’ll also be served well with an excellent set of high quality stainless steel pots and pans, with or without nickel, but be sure to never prepare acidic or tomato-based dishes in them. Always use an enamel-coated carbon steel or cast iron pot or Dutch oven for those foods. If baking in a metal dish or tray, using parchment paper is a great way to create a safe barrier between the food and metal surface. It will also save on the cleanup.
Knowing what goes into your cookware, as well as your food, is what makes a healthy meal. By educating yourself and making the right choices, dinner won’t just bring pleasure to your palate, but peace to your mind.
For more information on Dr. Sadeghi’s services and public presentations please visit him at Be Hive of Healing Integrative Medical Center. You can also sign up for his monthly holistic health newsletter or get a copy of his yearly wellness journal, MegaZEN. Dr. Sadeghi is the author of two books, Within: A spiritual awakening to love and weight loss, and The Clarity Cleanse: 12 steps to finding renewed energy, spiritual fulfillment, and emotional healing.