As our lifestyles become increasingly toxic, holistic practitioners are recognizing chemical and heavy metal toxicities as a key participant in the pathology of various chronic health conditions. In an attempt to clean up our environment and facilitate detoxification, we become aware of the need for clean air, water, food and a relatively chemical-free home environment. Toxic cookware is not always a topic broached with individuals, but considering the frequency with which individuals use cookware, it looks like it may be a pertinent part of the evaluation.
The prized ingredient of a vast majority of non-stick cookware, Teflon®, like many ingenious inventions, was discovered on accident. Teflon® came about when a Dupont chemist checked on a frozen sample of tetrafluoroethylene while experimenting with Freon® refrigerants and discovered a polymerized waxy solid, later patented as Teflon® and chemically known as polytetrafluoroethylene (PTFE). As non-stick cookware became increasingly common in American households, various academic and governmental studies sought to understand how PTFE responded to the high temperatures employed in most cooking. Unfortunately, it was found that PTFE released various toxic fumes at low temperatures and in a short period of time, routinely exposing millions of households to toxic substances. Coined as “polymer-fume fever” as early as 1951, the decomposition of pyrolysis in PTFE has been found to cause influenza-like symptoms, but some individuals may experience more severe pulmonary conditions. It has been suggested that the pathology of polymer-fume fever involves pro-inflammatory cytokine release, neutrophil activation, and oxygen radical formation, leading to pulmonary edema and pulmonary vascular permeability. The question of why Teflon® has remained present in most non-stick cookware, despite years of literature proving its toxicity, remains an enigma. The Washington Post reported in 2006 that Teflon® would be removed from all cookware by 2015; however, most consumers do not replace cookware often and, therefore, it can be reasonably assumed that Teflon® will remain in most consumers’ kitchens for years to come. As practitioners concerned about the effects of toxicity in health and healing, it is important to educate patients about the presence of PTFE in their own kitchens.
The prevalence of aluminum in the environment, occupational settings, and many cosmetics blurs the ability to pinpoint aluminum toxicity to cookware alone, and therefore, many continue to use aluminum cookware without concern. One author appropriately coined this the “aluminum age” and exposure, inevitable. Studies point to aluminum being a neurotoxin, and it certainly has found its way into the discussions of Alzheimer’s disease, estrogen-dominated cancers, and autism. How prevalent of a role it may play in these issues remains highly debatable (a discussion for another time), but regardless, aluminum seems to be something we should add to our ‘avoid’ list whenever possible. We also know that food remains the primary source of human exposure, aside from occupational exposure, so it only seems reasonable that we can aim to eliminate sources that are within our control, including aluminum cookware.
Copper is notoriously found in cookware because of its ability to conduct heat well and remains a favorite among commercial chefs. However, like aluminum, copper cookware will react with acids and salt, resulting in copper-tainted foods. Although an essential micronutrient, copper possesses oxidative-reductive properties that render it a contributor to oxidative stress, when present in excess. Recent studies are pegging copper as a possible target in the pathology of Alzheimer’s disease (AD) and Parkinson’s disease (PD), due to the efficiency by which astrocytes absorb, store and export copper. Astrocyte damage and dysfunction plays an important role in the development of neurodegenerative disease, such as AD and PD, raising concern about the healthfulness of routine use of copper cookware.
Cast iron has generally been regarded as a healthy form of cookware. It has even been recommended as a means of increasing iron consumption in menstruating women and others with the potential for iron-deficiency, owing to the fact that ferrous iron is released into acidic foods as they are cooked in cast iron. One study found a decrease in iron-deficiency anemia from 32.1 percent to 5.3% when routinely cooking acid foods in cast iron cookware for 12 weeks. While this may seem like a healthy outcome, there are many other individuals, including men and menopausal women, who would not benefit from excess iron, which is not easily eliminated. Iron is an oxidative agent, meaning excess iron can contribute to oxidative stress, cellular damage and long term health consequences, including cardiovascular disease.
Traditionally, stainless steel has been considered a safer option for cookware. Recent studies, however, are challenging this recommendation as various grades of stainless steel have been shown to leach nickel and chromium into cooked foods. Most commercial stainless steel is characterized as 18/10 or 18/8 stainless steel, representing the percentage of chromium and nickel alloys, respectively. Additional metals found in stainless steel cookware could include molybdenum, titanium, copper, iron and vanadium. Studies have found that nickel and chromium concentrations in acidic foods cooked in stainless steel often exceeded the tolerable upper limit for these metals, making a notable contribution toward increased cases of allergic contact dermatitis. Excess dietary nickel has also been implicated in eczema and other types of dermatitis. Higher grade surgical stainless steel is less likely to pose any significant risk of nickel or chromium toxicity and may be a safer option for sensitive individuals.
At this point, the task of finding safe cookware can seem daunting to the conscience consumer and concerned practitioner. Ceramic and enamel-coated cookware do not seem to pose any significant toxicities…. as of yet. Glass (so long as a verified lead-free product is chosen) is also an inert ingredient, not likely to pose any problems. More recently, titanium has been suggested as a safe, non-reactive material, but good luck trying to find it! It is also worth noting that not all the aforementioned materials may pose significant health risks to all individuals. For example, properly cared for cast iron may be perfectly safe for iron-deprived individuals, while a high grade stainless steel may not be a problem for those not sensitive to nickel or chromium. It is when health problems persist and metal toxicities are present that we must consider the impact cookware may have in individual cases. Food for thought indeed.
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