What’s the best type of pots and pans to use?
Stainless Steel or Cast Iron: Which Cookware Is Best? Is Teflon Safe?
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
In my last video, I expressed concerns about the use of aluminum cookware. So, what’s the best type of pots and pans to use? Stainless steel is an excellent option––the metal chosen in applications where safety and hygiene are considered to be of the utmost importance, such as kitchenware. But what about studies showing stainless steel can leach nickel and chromium into foods during cooking? (That’s what keeps the iron in the stainless steel unstained by rust.) The leaching is really only when they’re brand new. Metal leaching decreases with sequential cooking cycles and stabilizes after the sixth time you cook with it. Under more common day-to-day conditions, the use of stainless-steel pots is considered to be safe, even for most people who are acutely sensitive to those metals.
A little leaching metal can be a good thing in the case of straight iron, like a cast iron skillet, which can have the beneficial effect of helping to improve iron status, helping to potentially reduce the incidence of iron deficiency anemia among reproductive-age women and children. The only caveat is that you don’t want to be frying in cast iron. Frying isn’t healthy regardless, but at hot temperatures, vegetable oil can react with the iron to create trans fats.
What about using nonstick pans? Teflon, also known as polytetrafluoroethylene, is used as an inner coating material in nonstick cookware. Teflon’s dark history was the subject of a recent movie called Dark Waters, starring Mark Ruffalo and Anne Hathaway. Employees in DuPont’s Teflon division started giving birth to deformed babies before DuPont “removed all female staff” from the unit. Of course, they buried it all, hiding it from regulators and the public. Despite this significant history of industry knowledge about how toxic some of the chemicals used to make Teflon were, they were able to keep it all hidden. But eventually they were forced to settle for over a half a billion dollars after one of the chemicals was linked to kidney and testicular cancers, pregnancy-induced hypertension, ulcerative colitis, and high cholesterol.
“At normal cooking temperatures, [Teflon]-coated cookware releases various gases and chemicals that present mild to severe toxicity.” Here’s some of the different gases that are released at different temperatures, and the toxic effects that have been documented. You’ve heard of canaries in a coal mine? This is more like canaries in the kitchen, as cooking with Teflon cookware is well known to kill pet birds in the house; or Teflon-coated heat lamp bulbs wiping out half a chicken flock.
“Apart from the gases released during heating the cooking pans, the coating itself starts damaging after a certain period. It is normally advised to use slow heating when cooking in Teflon-coated pans,” but you can imagine how consumers might ignore that. And some of the Teflon can start chipping off if you’re not careful, and make its way into the food, though the effects of ingestion are unknown.
This is the only study I could find looking at the potential human health effects of cooking with nonstick pots and pans, and the use of nonstick cookware was associated with about a 50 percent increased risk of colorectal cancer. But that may be because of what they were cooking. Nonstick cookware is used in hazardous high-heat cooking methods, like broiling, frying, grilling, or barbecuing, mainly for meat, poultry, or fish, in which carcinogenic heterocyclic amines are formed from the animal protein. And then, the animal fat can produce another class of carcinogens, called polycyclic aromatic hydrocarbons––though it’s possible it was the Teflon itself, which contains suspected carcinogens like that C8 compound from the movie, also known as PFAO, perfluorooctanoic acid.
“Due to toxicity concerns, this chemical has been replaced with other chemicals such as GenX, but these new alternatives are also suspected to have similar toxicity.” But we’ve already so contaminated the Earth with it that now we can get it prepackaged in food before it’s even cooked––particularly in fish, dairy products, and meat, which is now the main source of human exposure to these toxic pollutants. Of those, seafood is the worst. In a study of diets from around the world, fish and seafood were major contributors of the perfluoroalkyl substances, as expected, given that everything eventually flows into the sea. Though the aquatic food chain is the primary transfer mechanism for these toxins into the human diet, “food stored or prepared in greaseproof packaging materials,” like microwave popcorn, may also be a source.
And in 2019, Oral-B Glide dental floss was tested. 6 out of 18 dental floss products they tested showed evidence of Teflon-type compounds. Here’s the list. So, did those who used those kinds of floss end up with higher levels in their bloodstream? Yes, apparently so. Higher levels of perfluorohexanesulfonic acid were found in Oral-B Glide flossers. There’s lots of environmental exposures in the modern world we can’t avoid, but we shouldn’t be making things worse by adding it to consumer products. But hey, at least it gives us some power to lower our personal exposure to these harmful chemicals.
Please consider volunteering to help out on the site.
- Guarneri F, Costa C, Cannavò SP, et al. Release of nickel and chromium in common foods during cooking in 18/10 (grade 316) stainless steel pots. Contact Derm. 2017;76(1):40-48.
- Kamerud KL, Hobbie KA, Anderson KA. Stainless steel leaches nickel and chromium into foods during cooking. J Agric Food Chem. 2013;61(39):9495-501.
- Kulkarni SA, Ekbote VH, Sonawane A, Jeyakumar A, Chiplonkar SA, Khadilkar AV. Beneficial effect of iron pot cooking on iron status. Indian J Pediatr. 2013;80(12):985-9.
- Alves C, Saleh A, Alaofè H. Iron-containing cookware for the reduction of iron deficiency anemia among children and females of reproductive age in low- and middle-income countries: A systematic review. PLoS ONE. 2019;14(9):e0221094.
- Kala AL, Joshi V, Gurudutt KN. Effect of heating oils and fats in containers of different materials on their trans fatty acid content. J Sci Food Agric. 2012;92(11):2227-33.
- Sajid M, Ilyas M. PTFE-coated non-stick cookware and toxicity concerns: a perspective. Environ Sci Pollut Res Int. 2017;24(30):23436-23440.
- Richter L, Cordner A, Brown P. Non-stick science: Sixty years of research and (in)action on fluorinated compounds. Soc Stud Sci. 2018;48(5):691-714.
- Lim X. The fluorine detectives. Nature. February 13, 2019.
- Boucher M, Ehmler TJ, Bermudez AJ. Polytetrafluoroethylene gas intoxication in broiler chickens. Avian Dis. 2000;44(2):449-53.
- Kontou N, Psaltopoulou T, Soupos N, et al. The role of number of meals, coffee intake, salt and type of cookware on colorectal cancer development in the context of the Mediterranean diet. Public Health Nutr. 2013;16(5):928-35.
- Sznajder-Katarzyńska K, Surma M, Cieślik I. A Review of Perfluoroalkyl Acids (PFAAs) in terms of Sources, Applications, Human Exposure, Dietary Intake, Toxicity, Legal Regulation, and Methods of Determination. J Chem. 2019.
- Haug LS, Thomsen C, Brantsaeter AL, et al. Diet and particularly seafood are major sources of perfluorinated compounds in humans. Environ Int. 2010;36(7):772-8.
- Pérez F, Llorca M, Köck-schulmeyer M, et al. Assessment of perfluoroalkyl substances in food items at global scale. Environ Res. 2014;135:181-9.
- Vestergren R, Cousins IT. 12 - Human dietary exposure to per- and poly-fluoroalkyl substances (PFASs). In: Rose M, Fernandes A, eds. Persistent Organic Pollutants and Toxic Metals in Foods. Woodhead Publishing; 2013:279-307.
- Boronow KE, Brody JG, Schaider LA, Peaslee GF, Havas L, Cohn BA. Serum concentrations of PFASs and exposure-related behaviors in African American and non-Hispanic white women. J Expo Sci Environ Epidemiol. 2019;29(2):206-17.
Video production by Glass Entertainment
Motion graphics by Avocado Video
- aluminum
- animal fat
- animal products
- barbecuing
- blood pressure
- cancer
- carcinogens
- cholesterol
- colitis
- colon cancer
- cooking methods
- dairy
- fish
- frying
- heavy metals
- high blood pressure
- hypertension
- industrial pollutants
- iron
- kidney cancer
- meat
- men's health
- oils
- persistent organic pollutants
- polycyclic aromatic hydrocarbons
- popcorn
- pregnancy
- seafood
- testicular cancer
- trans fats
- ulcerative colitis
- vegetable oil
- women's health
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
In my last video, I expressed concerns about the use of aluminum cookware. So, what’s the best type of pots and pans to use? Stainless steel is an excellent option––the metal chosen in applications where safety and hygiene are considered to be of the utmost importance, such as kitchenware. But what about studies showing stainless steel can leach nickel and chromium into foods during cooking? (That’s what keeps the iron in the stainless steel unstained by rust.) The leaching is really only when they’re brand new. Metal leaching decreases with sequential cooking cycles and stabilizes after the sixth time you cook with it. Under more common day-to-day conditions, the use of stainless-steel pots is considered to be safe, even for most people who are acutely sensitive to those metals.
A little leaching metal can be a good thing in the case of straight iron, like a cast iron skillet, which can have the beneficial effect of helping to improve iron status, helping to potentially reduce the incidence of iron deficiency anemia among reproductive-age women and children. The only caveat is that you don’t want to be frying in cast iron. Frying isn’t healthy regardless, but at hot temperatures, vegetable oil can react with the iron to create trans fats.
What about using nonstick pans? Teflon, also known as polytetrafluoroethylene, is used as an inner coating material in nonstick cookware. Teflon’s dark history was the subject of a recent movie called Dark Waters, starring Mark Ruffalo and Anne Hathaway. Employees in DuPont’s Teflon division started giving birth to deformed babies before DuPont “removed all female staff” from the unit. Of course, they buried it all, hiding it from regulators and the public. Despite this significant history of industry knowledge about how toxic some of the chemicals used to make Teflon were, they were able to keep it all hidden. But eventually they were forced to settle for over a half a billion dollars after one of the chemicals was linked to kidney and testicular cancers, pregnancy-induced hypertension, ulcerative colitis, and high cholesterol.
“At normal cooking temperatures, [Teflon]-coated cookware releases various gases and chemicals that present mild to severe toxicity.” Here’s some of the different gases that are released at different temperatures, and the toxic effects that have been documented. You’ve heard of canaries in a coal mine? This is more like canaries in the kitchen, as cooking with Teflon cookware is well known to kill pet birds in the house; or Teflon-coated heat lamp bulbs wiping out half a chicken flock.
“Apart from the gases released during heating the cooking pans, the coating itself starts damaging after a certain period. It is normally advised to use slow heating when cooking in Teflon-coated pans,” but you can imagine how consumers might ignore that. And some of the Teflon can start chipping off if you’re not careful, and make its way into the food, though the effects of ingestion are unknown.
This is the only study I could find looking at the potential human health effects of cooking with nonstick pots and pans, and the use of nonstick cookware was associated with about a 50 percent increased risk of colorectal cancer. But that may be because of what they were cooking. Nonstick cookware is used in hazardous high-heat cooking methods, like broiling, frying, grilling, or barbecuing, mainly for meat, poultry, or fish, in which carcinogenic heterocyclic amines are formed from the animal protein. And then, the animal fat can produce another class of carcinogens, called polycyclic aromatic hydrocarbons––though it’s possible it was the Teflon itself, which contains suspected carcinogens like that C8 compound from the movie, also known as PFAO, perfluorooctanoic acid.
“Due to toxicity concerns, this chemical has been replaced with other chemicals such as GenX, but these new alternatives are also suspected to have similar toxicity.” But we’ve already so contaminated the Earth with it that now we can get it prepackaged in food before it’s even cooked––particularly in fish, dairy products, and meat, which is now the main source of human exposure to these toxic pollutants. Of those, seafood is the worst. In a study of diets from around the world, fish and seafood were major contributors of the perfluoroalkyl substances, as expected, given that everything eventually flows into the sea. Though the aquatic food chain is the primary transfer mechanism for these toxins into the human diet, “food stored or prepared in greaseproof packaging materials,” like microwave popcorn, may also be a source.
And in 2019, Oral-B Glide dental floss was tested. 6 out of 18 dental floss products they tested showed evidence of Teflon-type compounds. Here’s the list. So, did those who used those kinds of floss end up with higher levels in their bloodstream? Yes, apparently so. Higher levels of perfluorohexanesulfonic acid were found in Oral-B Glide flossers. There’s lots of environmental exposures in the modern world we can’t avoid, but we shouldn’t be making things worse by adding it to consumer products. But hey, at least it gives us some power to lower our personal exposure to these harmful chemicals.
Please consider volunteering to help out on the site.
- Guarneri F, Costa C, Cannavò SP, et al. Release of nickel and chromium in common foods during cooking in 18/10 (grade 316) stainless steel pots. Contact Derm. 2017;76(1):40-48.
- Kamerud KL, Hobbie KA, Anderson KA. Stainless steel leaches nickel and chromium into foods during cooking. J Agric Food Chem. 2013;61(39):9495-501.
- Kulkarni SA, Ekbote VH, Sonawane A, Jeyakumar A, Chiplonkar SA, Khadilkar AV. Beneficial effect of iron pot cooking on iron status. Indian J Pediatr. 2013;80(12):985-9.
- Alves C, Saleh A, Alaofè H. Iron-containing cookware for the reduction of iron deficiency anemia among children and females of reproductive age in low- and middle-income countries: A systematic review. PLoS ONE. 2019;14(9):e0221094.
- Kala AL, Joshi V, Gurudutt KN. Effect of heating oils and fats in containers of different materials on their trans fatty acid content. J Sci Food Agric. 2012;92(11):2227-33.
- Sajid M, Ilyas M. PTFE-coated non-stick cookware and toxicity concerns: a perspective. Environ Sci Pollut Res Int. 2017;24(30):23436-23440.
- Richter L, Cordner A, Brown P. Non-stick science: Sixty years of research and (in)action on fluorinated compounds. Soc Stud Sci. 2018;48(5):691-714.
- Lim X. The fluorine detectives. Nature. February 13, 2019.
- Boucher M, Ehmler TJ, Bermudez AJ. Polytetrafluoroethylene gas intoxication in broiler chickens. Avian Dis. 2000;44(2):449-53.
- Kontou N, Psaltopoulou T, Soupos N, et al. The role of number of meals, coffee intake, salt and type of cookware on colorectal cancer development in the context of the Mediterranean diet. Public Health Nutr. 2013;16(5):928-35.
- Sznajder-Katarzyńska K, Surma M, Cieślik I. A Review of Perfluoroalkyl Acids (PFAAs) in terms of Sources, Applications, Human Exposure, Dietary Intake, Toxicity, Legal Regulation, and Methods of Determination. J Chem. 2019.
- Haug LS, Thomsen C, Brantsaeter AL, et al. Diet and particularly seafood are major sources of perfluorinated compounds in humans. Environ Int. 2010;36(7):772-8.
- Pérez F, Llorca M, Köck-schulmeyer M, et al. Assessment of perfluoroalkyl substances in food items at global scale. Environ Res. 2014;135:181-9.
- Vestergren R, Cousins IT. 12 - Human dietary exposure to per- and poly-fluoroalkyl substances (PFASs). In: Rose M, Fernandes A, eds. Persistent Organic Pollutants and Toxic Metals in Foods. Woodhead Publishing; 2013:279-307.
- Boronow KE, Brody JG, Schaider LA, Peaslee GF, Havas L, Cohn BA. Serum concentrations of PFASs and exposure-related behaviors in African American and non-Hispanic white women. J Expo Sci Environ Epidemiol. 2019;29(2):206-17.
Video production by Glass Entertainment
Motion graphics by Avocado Video
- aluminum
- animal fat
- animal products
- barbecuing
- blood pressure
- cancer
- carcinogens
- cholesterol
- colitis
- colon cancer
- cooking methods
- dairy
- fish
- frying
- heavy metals
- high blood pressure
- hypertension
- industrial pollutants
- iron
- kidney cancer
- meat
- men's health
- oils
- persistent organic pollutants
- polycyclic aromatic hydrocarbons
- popcorn
- pregnancy
- seafood
- testicular cancer
- trans fats
- ulcerative colitis
- vegetable oil
- women's health
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Stainless Steel or Cast Iron: Which Cookware Is Best? Is Teflon Safe?
LicenseCreative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Content URLDoctor's Note
This is the second in a three-video series on cookware. The first was Are Aluminum Pots, Bottles, and Foil Safe?, and the next is Are Melamine Dishes and Polyamide Plastic Utensils Safe?
What about pressure cooking? I covered that in Does Pressure Cooking Preserve Nutrients?
So what is the safest way to prepare meat? See Carcinogens in Meat.
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