Are There Side Effects Of Using Cast Iron Pans To Cook?

Are you an owner of a cast iron pan? You’ll know that using cast iron pans in the kitchen has many benefits. But could there be side effects of using cast iron pans to cook? If you’ve asked such questions, then you are at the right place. We’d be discussing the side effects of cast iron pans. It’d be great if you read through.

Analyzing cast iron

Cast iron cookware is made by melting blocks of iron and steel together in a factory. Then chemicals are added to the mixture in order to raise its carbon levels. Next, the molten metal is poured into a mold made of sand, water, and powdered clay.

Cast iron pans have been used for hundreds of years to sear, saute, roast, stew, and bake an array of food items. While the versatile pan is a favorite among chefs, you may have concerns about the side effects of iron utensils if you’re worried about iron overload.

When the cast iron pot or pan is cool, the sand mold is broken and the cookware is released. Workers then smooth each piece before it’s ready to be sold.

The first known use of cast iron cookware was during the Han Dynasty in China, around 220 A.D. Casting techniques became widespread in Europe by the 16th century, and since then, this versatile equipment has been a staple in households all over the world. In 1707, Abraham Darby patented the sand casting method, which is similar to the way we make cast iron today.

Cast iron is relatively easy to analyze, as far as health effects go. It’s made out of … iron. Not like the more complex pans, which have multiple layers or man-made coatings. So let’s start by talking a little bit about iron.

You can’t just dig up pure iron from the ground. Pure iron is rare and mainly comes from fallen meteorites. And it’s actually pretty soft, so not great for making pans without adding in some carbon for hardening. But still, around 97-98% of a cast iron pan is plain ol’ iron, which is why we’re so interested in its health effects. Our discussion also applies to carbon steel cookware (such as woks), which is made up of 99% iron.

Cast iron and carbon steel pans are very similar in their makeup and kitchen use, so potential health concerns from cast iron pans also apply to carbon steel pans, which are also known as “blue steel” or “black steel” pans.

Iron is also an essential dietary mineral. And cooking on a cast iron pan can transfer some of that mineral from the pan to the food to your body. Some will see this as a good thing, especially considering that 1.6 billion people around the world are anemic, with iron deficiency being the main cause. But iron-deficiency anemia in the US is much less common, with 5 million people having iron-deficiency anemia.

So when most people think of iron, they think of getting enough iron. Iron is one of the few nutrients that a doctor will ask you about, and iron even takes up one of the coveted nutrient spots on the US nutrition label! But the same property that makes iron so useful in the body, its ability to give or receive electrons, makes it potentially harmful when you ingest too much, due to increased production of free radicals.

Too much iron has been linked to a wide variety of conditions, such as Alzheimer’s, heart disease, and colorectal cancer to name just a few. There are a couple of groups of people who don’t have to worry quite as much about iron overload though: menstruating women and vegetarians/vegans. But for others, especially those who regularly eat red meat, it doesn’t take much to push yourself into the excess iron territory.

Is Cast Iron Dangerous?

Too much iron is a concern for people with hemochromatosis, a medical condition that increases iron absorption from food and can lead to life-threatening problems. There’s also evidence that too much iron in the blood increases the risk of cancer. However, while you may consider these health concerns to be disadvantages of cast iron cookware, the use of iron utensils may not have much of an effect in either case.

Cast iron cookware may take a long time to heat to the proper cooking temperature, but provides an even source of heat after it is hot, according to Utah State University Extension. The metal pots are also able to withstand very high temperatures, which makes them ideal for searing meat to lock in flavor.

However, the iron in cast iron pans causes a chemical reaction with high-acid foods, such as tomatoes and wine, which may oxidize the pan. But if you season your cast iron pan well prior to cooking anything acidic, you can prevent this reaction. Properly seasoning your cast iron pan also prevents the cookware from rusting.

To season your cast iron pan, coat the entire pain (inside and out) with oil or shortening and bake in the oven at 400 degrees Fahrenheit for an hour, suggests the West Virginia Department of Agriculture. You will need to re-season it periodically to maintain the quality of your cast iron pan. The frequency of your seasoning may depend on how often you use your cast iron cookware.

One of the side effects of iron utensils, which can be good and bad depending on your needs, is that they may add iron to your food. Iron is an essential mineral your body needs to make red blood cells. An adequate intake of iron also supports physical growth and neurological development in children and teens.

Not getting enough iron in your diet may lead to iron-deficiency anemia. Children, pregnant women, and premenopausal women are at the greatest risk of not getting enough iron to meet their needs, according to the Office of Dietary Supplements. Your daily iron needs vary based on your age and gender:

  • Infants birth to 6 months (both genders): 0.27 milligram
  • Infants 6 to 12 months (both genders): 11 milligrams
  • Children 1 to 3 years (both genders): 7 milligrams
  • Children 4 to 8 years (both genders): 10 milligrams
  • Children 9 to 13 years (both genders): 8 milligrams
  • Male teens 14 to 18 years: 11 milligrams
  • Female teens 14 to 18 years: 15 milligrams
  • Males 19+ years: 8 milligrams
  • Females 19 to 50 years: 18 milligrams
  • Females 51+ years: 8 milligrams
  • Pregnant women: 27 milligrams
  • Lactating women: 8 to 9 milligrams

Women of childbearing years have higher iron needs than men due to blood loss from menstruation.

As well as obtaining iron through your diet it is also possible to increase your iron intake through the use of a cast-iron pan, which can be extremely useful for the latter of the aforementioned population groups with minimal additional effort!

The amount of iron added to the food from cast iron utensils depends on the moisture, acidity, and length of cooking time. According to the advice site Go Ask Alice at Columbia University, cooking 100 grams of tomato sauce in a cast iron pan increases iron content from 0.6 milligrams to 5.7 milligrams. The significant increase in iron may be due to the long cooking time needed to make tomato sauce, as well as its high acidity content.

By comparison, the iron content in hamburgers, cornbread or liver and onions doesn’t increase as much. This may be due to a shorter cooking time or the frequent turning needed to cook some of these foods.

Hemochromatosis Cast Iron Cooking

Many groups of people benefit from getting more iron in their diet, including women and children. But too much iron in the diet isn’t good for everyone, such as those with hemochromatosis, which may be viewed as one of the disadvantages of cast iron cookware.

Hemochromatosis causes your body to absorb an excessive amount of iron from food, according to the Mayo Clinic. Your body then stores the excess iron in your liver, pancreas and heart, which increases risk of liver disease, diabetes and heart disease.

The primary treatment for hemochromatosis includes regular blood draws, not an iron-restricted diet. According to the National Institute of Diabetes and Digestive and Kidney Disorders, if you have hemochromatosis the only recommended diet change is to consume moderate amounts of red meat and organ meats. In addition to being high in iron, these meats also contain heme iron, which is better absorbed than the non-heme iron found in plant foods.

Limiting your intake of alcohol is also recommended if you have hemochromatosis in order to reduce the risk of liver damage.

If you have hemochromatosis, you also need to avoid the use of iron and vitamin C supplements. While the Iron Disorders Institute suggests that you cook with glass or ceramic cookware when your iron levels are high, there are no restrictions on the type of cookware you use when your iron levels are within normal range.

The Benefits of Cast Iron pans

“Research has shown an increased level of iron in foods cooked in cast-iron cookware — especially high-acid foods that encourage the leaching of iron out of the pan, like eggs or tomatoes,” says Ella Davar, RD, an integrative nutritionist based in New York.

“The greater the acidity of the food and the longer you cook it, the more iron is transferred.”


Cast-iron pans transfer small amounts of iron into food while cooking, which may help infuse your dish with the hemoglobin-producing mineral. FYI, iron produces the protein hemoglobin, which carries oxygen to red blood cells throughout the body, according to the National Institutes of Health (NIH).


There are many reasons to use cast-iron cookware, but if you want more iron in your diet, it’s best not to count on the skillet for anything more than trace amounts. Instead, eat more high-iron foods, like oysters, clams, mussels, canned sardines, canned light tuna, as well as beef, poultry, chicken liver and other organ meats.