I switched to cast-iron skillet/griddle (dont know what it's technically called) recently for my omelette because I read somewhere that non-stick coating can leak carcinogen during cooking

For cast-iron pan, I see how it is recommended to season it via the oil-bake method - the coating that will then help avoid food sticking to the pan and for its longer shelf life

I want to understand that, will the oil, when heated to high temperatures for the effect of seasoning, will that oil become a carcinogen? Am I borrowing (carcinogen) from peter(cast-iron) to pay paul(non-stick)?

  • 1
    I really like this question, I'm glad it was asked!
    – Tad Jones
    Feb 22, 2021 at 5:19
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    Sorry, any health related questions are off topic here.
    – rumtscho
    Feb 22, 2021 at 7:36
  • 2
    You should ask this in the Skeptics site.
    – RedSonja
    Feb 22, 2021 at 13:50
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    @rumtscho: might be better to reopen it. I've given it a canonical answer, and if we leave this question as open and answered, then we can bounce any of the many related questions we're liable to get in the future.
    – FuzzyChef
    Feb 22, 2021 at 22:41
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    @FuzzyChef I recognize that you diligently researched the matter before forming an opinion. After years of working in medical science, I can tell you that finding out the actual answer requires a five-year project led by an experienced cancer biologist, not a brief literature search. Your answer is well-written, very convincing - but nobody on the site can recognize whether it is really correct, while subjectively feeling very convincing. This is why the site has decided, since the very beginning, to not allow this type of question and answer for health topics. I know how frustrating it feels,
    – rumtscho
    Feb 23, 2021 at 13:40

1 Answer 1


So, after a quick literature search:

There is no published evidence of cast iron seasoning carrying any special carcinogenic elements, aside from those carried by any kind of high-heat cooking in any kind of cookware. If there's a danger from cast iron, it's folks who season their cast iron in an unventilated kitchen, since the burnt oil fumes are not good for you, and the fact that folks sometimes heat cast iron to higher heats than they would other cookware, just because they can.

For that matter, quality modern nonstick cookware in many countries also lacks known carcinogens. Teflon coatings used to consist of PTFE and PFOA, of which only the PFOA is a known cancer risk. For that reason, most manufacturers in the US and Europe have made PFOA-free nonstick cookware since 2013. PTFE, the substance that actually resists stickiness, is so inert and harmless it's used to coat medical instruments. Like cast iron, the main danger is if you overheat the pan, which does release substances that are bad for your lungs (also ruins the pan).

Heck, you can even today choose from an array of pans that have a non-PTFE nonstick coating.

Given all this, there are many reasons for you to chose cast iron vs teflon cookware (or even carbon steel, or many other options), but cancer risk shouldn't be one of the reasons.

  • did not know about the PTFE on medical instruments part (will check what happens to it on high-heat though still). That non-PTFE nonstick is even wonderful, thanks for taking out the time to share all the knowledge!
    – gawkface
    Feb 22, 2021 at 8:22

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