The Iron Pan Paradox: Do Cast Iron Pans Really Add Iron To Your Food?

Cooking in a cast-iron pan can add a significant amount of iron to your food and body. Iron is an essential nutrient, responsible for transporting oxygen through haemoglobin in the blood and myoglobin in muscles. While eating iron-rich foods like meats, beans, and spinach can boost your iron intake, cooking with cast iron is another easy way to increase the iron content of your meals.

Acidic foods absorb the most iron

Acidic foods are more likely to absorb iron from cast iron pans. Researchers have found that cooking in an iron skillet increases the iron content of many foods, with acidic foods that have a higher moisture content absorbing the most iron. For example, the iron content in 100 grams of spaghetti sauce jumped from 0.6 mg to 5.7 mg after being cooked in a cast iron pot.

Cheng and Brittin's study found that when cooked in cast iron pots, the spaghetti sauce picked up about 2 mg of iron per 100 g of sauce, and applesauce picked up 6 mg per 100 g.

Acidic foods that can be cooked in cast iron pans to increase iron intake include:

• Applesauce
• Chili
• Tomato sauce
• Stew
• Scrambled eggs
• Citrus fruits
• Dark green leafy vegetables
• Bell peppers
• Melons
• Strawberries

Longer cooking times increase iron content

Longer cooking times do indeed increase the iron content of food cooked in cast iron pans. This is because the longer cooking time allows for more individual atoms of iron to either flake off or be chemically absorbed by the food.

A study by Y.J. Cheng and H.C. Brittin, published in the Journal of Food Science in 1991, tested this theory. They cooked 100 batches of applesauce and 100 batches of spaghetti sauce in cast-iron pots and 100 batches of each in CorningWare glass dishes. The study found that the longer cooking time of the sauces in the cast-iron pots resulted in a higher iron content than the same sauces cooked in the glass dishes. The spaghetti sauce cooked in the cast-iron pots had about 2 mg of iron per 100g of sauce, while the applesauce had 6 mg per 100g. In comparison, the iron content of the sauces cooked in the glass dishes was negligible, with less than one milligram of iron per 100 grams of food.

Another factor that increases the iron content of food cooked in cast iron pans is the acidity of the food. Acidic foods, such as applesauce and spaghetti sauce, have a greater propensity to absorb iron. This is because the acid in the food reacts with the iron in the pan, causing it to be released into the food.

It is important to note that not all foods absorb iron from cast iron pans equally. For example, foods with shorter cooking times, such as hamburgers, corn tortillas, cornbread, and liver with onions, may not absorb as much iron. This is because they have less contact with the iron due to the shorter cooking time. Additionally, dry, non-acidic foods like pancakes, rice, and green beans also do not pick up much iron from a cast iron pot.

Using a newer cast iron skillet can also increase the iron content of food. This is because newer skillets have more iron to impart to the food than well-seasoned or older skillets.

Overall, cooking in a cast iron skillet can be an effective way to boost your iron intake, especially for those who are anaemic or iron deficient. However, it is important to be aware that cast iron pans should not be used for deep-frying as iron can oxidize fats, causing the cooking oil to become rancid.

Iron from cast iron is nonheme iron

Cooking in cast iron cookware can add significant amounts of iron to food. However, the iron derived from cast iron is non-heme iron, which is less readily absorbed by the body than heme iron. Non-heme iron is found in plant-based foods like grains, beans, vegetables, fruits, nuts, and seeds, as well as animal products such as eggs and dairy.

Non-heme iron is not as easily absorbed by the body as heme iron, which is found only in animal proteins such as meat, poultry, seafood, and fish. This is why vegetarians are more at risk of developing iron-deficiency anaemia than those who eat meat. During digestion, the body has to alter non-heme iron to absorb it fully.

The absorption rate of non-heme iron is approximately 5-12% of the iron listed on the nutritional label for people without hemochromatosis. In contrast, 20-30% of the heme iron consumed is typically absorbed from a meal.

While cast iron cookware can add iron to food, the amount of iron transferred is generally not enough to pose any risk of iron overload in healthy individuals. However, it can be a convenient way to boost iron intake, especially for those with anaemia.

To maximise the amount of iron transferred from cast iron cookware to food, use a newer iron skillet, cook acidic and moist foods, and increase cooking time and stirring. Examples of foods that absorb more iron during cooking include applesauce, spaghetti sauce, tomato sauce, and scrambled eggs.

Cast iron skillets are not ruined by rust

Cast iron skillets are resilient and can be saved even if they have rusted. Rust (iron oxide) forms when iron reacts with oxygen and water. Therefore, cast iron skillets can rust if you leave water on them for too long. It is important to dry your cast iron skillet with a paper towel or lint-free cloth after washing. You can also place it on the stovetop on low heat for a few minutes to ensure it is completely dry.

If your cast iron skillet does develop rust, there are several steps you can take to remove it. Firstly, scrub and wash your pan. Scour the rusty sections with steel wool or a scouring pad under cold water. Then, wash the pan with warm, soapy water. This step may remove portions of the seasoning, but that is okay because you will be re-seasoning the pan.

Completely dry your cast iron skillet with a paper towel or lint-free cloth. You can place it on the stovetop on low heat for a few minutes to make sure it is completely dry. Then, add a very thin layer of cooking oil to the entire surface of your cast iron with a cloth or lint-free paper towel.

Preheat your oven to between 450 and 500 degrees Fahrenheit. Place aluminium foil on the bottom rack of the oven to catch any excess oil. Put your cookware upside down on the centre rack. Bake for 1 hour, then turn off the heat and allow the cast iron skillet to cool in the oven. This allows the seasoning to further cure and adhere to the iron.

In conclusion, while rust can be detrimental to cast iron skillets, it does not necessarily ruin them. With the proper care and maintenance, rust can be removed and the skillet can be restored to its former glory.

Cast iron is not non-stick

While cast iron pans can be seasoned to create a non-stick finish, they are not naturally non-stick like Teflon pans. In fact, when you're first learning how to use cast iron, everything might seem to stick.

To create a non-stick finish on a cast iron pan, you must bake oils or fats onto the cookware. This process is called seasoning. Oils with a hard finish, such as lard, tallow, or coconut oil, are best for this. The more coats of seasoning you apply, the smoother and more non-stick the finish will be. However, this finish is not permanent and will wear down over time, so cast iron pans must be re-seasoned every 6-12 months.

Even a well-seasoned cast iron pan is not as non-stick as a Teflon pan. You cannot, for example, cook a load of cold eggs in a cast iron pan without oil and then slide them out without any sticking. However, if your cast iron pan is well-seasoned and you pre-heat it before adding food, you should have no problems with sticking.

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