December 21, 2023
Are you looking to get the most out of your cookware? Teflon and nonstick pans were once a staple of the midcentury family kitchen. But how did the manufacturers manage a nonstick coating? Learn about the risks of Teflon and the PFA chemicals used to treat these types of cookware - and discover the many varieties of safer coating alternatives with Monica on today's episode Ask a Nutritionist!
MONICA: Welcome to Dishing Up Nutrition's "Ask a Nutritionist" podcast brought to you by Nutritional Weight and Wellness. We're thrilled to be celebrating 20 years on air discussing the connection between what you eat and how you feel while sharing practical real life solutions for healthier living through balanced nutrition. Thank you for your support and listenership over the years.
My name is Monica Hoss. I am a Registered and Licensed Dietitian. And today I'm going to be answering two questions from Dishing Up Nutrition listeners. So the first question is, “In detoxing your home, are ceramic pots marketed as safe alternatives to non-stick Teflon pans safe?”
We also got a second question about cast iron cookware that I'm also going to address since it fits nicely. It reads, “I see some cast iron pans are seasoned with vegetable oil. Is this a concern or doesn't that matter?” These are great questions, so let's dig in.
And I want to start by giving a little background on non-stick cookware, what they are made from and why it might be in our best interest to avoid traditional nonstick cookware. So in the 1950s and 1960s cookware by Teflon, so that's the brand name for these nonstick pans, became a household staple. Nonstick cookware contains PFAs, which are chemicals that were invented in the 1930s.
These chemicals are water, grease, and stain resistant, and they're used in a lot of things, not just cookware. They sound very appealing because we all know the pain of washing a pan that has food stuck in it. It's not fun. But really, in recent decades, we've been learning that PFAs may be harming our health.
Now, PFAs are known as forever chemicals because they don't naturally break down. So they stay in our bodies and our environment, well, forever. And as a result, they bioaccumulate over time, making them a highly concerning chemical group. PFA base coatings also release toxic fumes when overheated. PFAs are hormone disruptors and have been linked to certain cancers, immune disorders, altered thyroid regulation , reproductive problems, and even birth defects.
And unfortunately, they are found everywhere, even in our drinking water. And I also want to note that even though we're talking specifically about cookware, really, anything that's labeled as non-stick, whether it's a frying pan, a waffle maker, roasting pan, pressure cooker, slow cookers, these all have the potential to be coated in the Teflon and traditional non-stick. So there's just a lot of unknowns about these chemicals and I would suggest avoiding traditional non-stick items; may or may not be labeled as Teflon.
But fortunately these days there are nonstick alternatives that don't contain PFAs. And our original question asked specifically about ceramic pots and pans that are marketed as safe alternatives. So I want to start there. The inside of a ceramic pot or pan is coated with water and oil resistant coating on top of a metal base, which is usually made of stainless steel or aluminum, and that's made of silicone oxide.
Now, despite the name, ceramic cookware doesn't actually contain any ceramic. Rather, the name comes from the coating's glossy enamel like appearance. Ceramic cookware is often marketed as a safer, more sustainable alternative to regular nonstick cookware and one that can safely be used at much higher temperatures without starting to break down.
Now here's where it gets tricky because ceramic pans, they claim to be non-toxic and safe because they don't have PFAs, heavy metals, polymers, coatings, and dyes. However, it is hard to find a lot of information on what is actually in the coating. And some suspicion has been raised in recent years.
So I would really encourage you to do research on each individual company and the quality and safety of their products. A few of the popular ceramic pan companies have recently disclosed the use of nanoparticles in their coatings. The use of nanoparticles is common but not well studied. However, some titanium dioxide nanoparticles have been linked to precancerous gut lesions as well as immune disruption .
There are also two other considerations to take into account. One, the coating on a ceramic pot or pan tends to be more delicate, so it's going to be more susceptible to scratches and other forms of wear and tear. So if you do see any damage to the coating, I would stop using it.
And the second consideration is that even though many ceramic pans are marketed as safe for high heat cooking, we know that sustained high heat can cause the ceramic coating to break down more quickly. So I really wouldn't recommend using ceramic cookware for high heat or searing.
And, in full disclosure, I have ceramic cookware at home, but really in researching for this episode, I, I think I'm going to choose ceramic cookware when I really need something to be non-stick, like for making eggs. But, we just don't know enough information about what is in this cookware, so going forward, I'm going to limit my use.
Thankfully, ceramic cookware isn't the only alternative. Stainless steel is highly regarded as safe because it is generally not reactive with foods. So, this is great to use for that high heat cooking and searing. However, you do want to be careful because sometimes they have aluminum or copper coatings on the bottom to improve heat transfer. So, any damage, again, to the cooking surface could increase risk of the heavy metals leaching into your food.
Now stainless steel is pretty sturdy. But again, if you see damage, you should stop using your pan. And here's a little tip: to make stainless steel nonstick you want to preheat it at a low to medium heat for several minutes. So just be patient and then you're going to want to use a good amount of butter or avocado oil, coconut oil once the pan is hot. This will make it non-stick.
But there is a learning curve to figuring out stainless steel cookware, but once you do, they are amazing and a favorite among a lot of cooking professionals and home cooks. So stainless steel would be a great alternative.
Another option is tempered glass. This is produced for high temperature cooking as well and is very safe and non-toxic. However, glass can shatter so you really have to be careful and follow the product recommendations if you're going to go this route.
One other option is cast iron. So these are very durable pans that can go from stovetop to oven. And these are wonderful for creating that nice crust for searing, browning meat, and cooking bacon. Now they do take a little special care and attention, and generally you don't want to cook anything acidic in it like tomato sauce.
Now, cast iron will be naturally non-stick if, again, you use lower heat and plenty of avocado, coconut oil. Now, cast iron retains heat very well, so if you heat it too high, food will actually stick. So it's definitely a Goldilocks effect. You don't want it, too hot and you want it to be heated before you start using it so that it'll be non-stick. Again, there's a learning curve and you need to be patient.
Another important factor to consider with cast iron is that it needs to be seasoned. So, when oil or fats are heated in cast iron at a high enough temperature, they will change from a wet liquid into a slick, hardened surface through a process called polymerization.
This reaction creates a layer of seasoning that is molecularly bonded to the iron. Okay, so that's a lot of science, but without this layer of carbonized oil, the iron cookware could corrode and rust due to the oxygen and moisture in the air, and in our cooking. So this brings us to the second question about cast iron pans being seasoned with refined oils like vegetable oil.
And I think what this listener may be asking is that a lot of times when you buy a cast iron pan, most of them are pre-seasoned with a vegetable oil. If you are a regular listener, then you know we recommend avoiding refined oils. And in doing research for this episode, I found that it might not be a big concern because the oil gets polymerized and then it hardens into that coating on the cast iron.
So the oil is not actually leaking into your food. So you're probably okay buying the pre-seasoned pan, and then when it comes to the upkeep of it, you can use coconut oil or avocado oil to season your cast iron pan going forward. But of course you could also find a brand that doesn't pre-season the pans and then just do your own seasoning.
Okay, that was a lot of information to cover. So I just want to summarize. It's probably best to use stainless steel or cast iron pans for the majority of your cooking since these seem to be the safest. Ceramic pans are more of like an occasional use like for eggs. Since again, we just, we really don't know enough about the materials used.
I would avoid anything that is traditional, non-stick, Teflon-like material. And I hope the information in today's show will help guide you in making the best decisions in choosing cookware for your family.
Thanks for listening to Dishing Up Nutrition's “Ask a Nutritionist”. If you have a nutrition question that you would like us to answer, we invite you to join our nutrition Facebook community called Dishing Up Nutrition on Facebook. Have a great day.