Iron and Carcinogens in Cast Iron

09 Aug.,2022

 

Chinese cast iron skillet

 

Question:
I have used iron skillets for years. Some belonged to my Mother. A friend asked me if it was safe to use because of the iron in the skillet. I told her I have been eating from them and using them for years & never heard anything about the iron in the skillet not being safe. Please let me know. Thank-you for your informative care of the skillets. – Brenda Weldon (12/16/05)

 

Answer:
Yes, cooking in a cast iron skillet can add significant amounts of iron to your food and into your body… if you eat it. This was proven by researchers who tested 20 foods, the results of which were published in the July 1986 issue of the Journal of the American Dietetic Association. They measured the iron and moisture content of these items when raw, and after cooking in an iron skillet and a non-iron (Corning ware) dish, separately. A new, seasoned iron skillet was used, in the event prior use might have affected iron absorption. The researchers also compared iron absorption when using a new iron skillet versus an older one.

Researchers found that cooking in an iron skillet greatly increases the iron content of many foods. Acidic foods that have a higher moisture content, such as applesauce and spaghetti sauce, absorbed the most iron. As a matter of fact, the big winners in the foods tested were these two items. For 100 grams of each (about 3 oz.), the applesauce increased in iron content from 0.35 mg. to 7.3 mg., and the spaghetti sauce jumped from 0.6 mg. to 5.7 mg. of iron.

Food cooked for longer periods of time absorbed more iron than food that was heated more quickly. They also found foods prepared with a newer iron skillet absorbed more iron than those cooked in an older one. Foods that were cooked and stirred more frequently absorbed a greater amount of iron as well, probably because they came into contact with the iron more often. Hamburger, corn tortillas, cornbread, and liver with onions didn’t absorb as much iron. This was probably due to the shorter cooking times, and the fact that they were either turned once or not at all, resulting in less contact with the iron.

Here are the changes the researchers found. Foods cooked at home may vary in iron absorption based on the age of the skillet used and the amount of time the foods are heated. This list can give you a general idea of the difference in dietary iron content cooking in an iron skillet can provide.

Foods tested (100 g./3 oz.)Iron content - rawIron content - cooked in Cast iron  
Applesauce, unsweetened.35 mg.7.38 mg. Spaghetti sauce0.615.77 Chili with meat and beans.966.27 Medium white sauce.223.30 Scrambled egg1.494.76 Spaghetti sauce with meat.713.58 Beef vegetable stew.663.4 Fried egg1.923.48 Spanish rice.872.25 Rice, white.671.97 Pan broiled bacon.771.92 Poached egg1.872.32 Fried chicken.881.89 Pancakes.631.31 Pan fried green beans.641.18 Pan broiled hamburger1.492.29 Fried potatoes.42.8 Fried corn tortillas.861.23 Pan-fried beef liver with onions3.13.87 Baked cornbread.67.86

 

So, if you’re looking to increase your dietary iron, use a new cast iron skillet. After all, the iron in cookware is no different from the iron in our bodies — except we have much smaller amounts!

 

 

Question:
A friend recently said that she’d read that cast iron cookware gives of carcinogens. Is this true? – Gary Hollingshead (11/28/05)

 

Answer:
I have not read any articles on cast iron cookware containing carcinogens. If you have some articles, please share them with me.

Cooking in cast iron pots can significantly increase the iron content of food, particularly foods with a high moisture content, high acidity and those cooked for a long time. For example, a serving of spaghetti sauce normally contains less than one milligram of iron, but when cooked in an iron pot, that can climb to nearly six milligrams. Whether or not this added iron is a benefit depends on your age and your health status. For most individuals the occasional use of a cast iron skillet will cause no health concerns

I have read that everything grilled or barbecued is full of carcinogens due to the fact that the food is cooked over burning coals, wood and/or gas. The carcinogens intrinsically produced in grilling are mainly free radicals that are produced whenever you heat a hydrocarbon (i.e. butter, fat, burnt-sugar, etc.) to high temperatures. This is why French fries are so unhealthy – not only are they high in fat but they are also loaded with free radicals.

I have also heard that Teflon pans contain carcinogens. A University of Toronto chemist has shown that Teflon coated pans release perfluorooctanoic acid (PFOA), a “likely carcinogen” and other chemicals when heated to 360 celsius.

Did you know that even black pepper contains 32 known carcinogens?

Feedback:
Wow! Pepper has 32 carcinogens!? That is nothing to sneeze at!

 

 

Question:
I am on a nutrition web program and one of our members brought up the question of how much iron is given off a cast iron skillet into the food you are cooking. Are you aware of any research on this subject? It would be one more benefit to using cast iron skillets. – Cathryn (10/15/05)

 

Answer:

Cooking high-acid foods like tomato products or apple sauce in cast iron cook-ware is actually recommended to help increase the amount of iron in your diet.

In fact, in a classic study published in 1986 in the Journal of the American Dietetic Association, researchers tested 20 foods cooked in new cast iron skillets. They found most foods increased in iron content by being cooked in the iron cookware, some significantly so.

Check out all my web pages on cast iron pots, kettles, and Dutch ovens:

 

Main Page:
The Irreplaceable Cast Iron Skillet

 

Question & Answer Pages:

Ceramic Top (Flat Top) Electric Range and Cast Iron Pots

Hot Fire for Curing & Cleaning

Iron and Carcinogens in Cast Iron

Misc. Questions & Answers

Pre-Seasoned Cast Iron Pots

Salt for Cleaning Cast Iron

Sanding Cast Iron Pots

Self-Cleaning Oven for Cleaning & Seasoning

Warped or Cracked Cast Iron Pots

Washing Cast Iron Pots