If you’re searching for a cast iron expert, I think I qualify. In my early twenties I worked as a customer service agent for a small cast iron skillet company, and I’ve answered every question about this cookware as you can imagine — how to clean it, store it, remove rust from it, cook an egg in it, and much more. But one of the more common, and less expected, questions I received was: Does cooking in cast iron add iron to food?

The short answer is yes! Preparing meals in cast iron pots, pans, Dutch ovens, and cornbread molds can boost the iron content in what you’re eating. This is a simple strategy to up the iron in your diet if you suspect you’re not getting enough or supplement efforts to fight an iron deficiency, and it’s important information if you’re someone whose iron levels are too elevated — but there are a few key caveats when considering whether cast iron is the right way to get more of this metal. Here’s everything you need to know about adding iron to your diet by using this timeless cookware.

How much iron does cast iron add to food?

The exact amount of iron that food will absorb depends on a few variables, like what you’re cooking and how long it’s in the skillet. But a 2013 study out of the School of Health Sciences in India’s University of Pune gives a good point of reference for the rough degree to which the metal’s presence will escalate: When four iron-rich snacks for children were cooked in cast iron pots, their iron content increased by 16.2% compared to snacks that were cooked in Teflon-coated nonstick pans. Other sets of published research also confirm that cooking in cast iron can raise the iron content in food, but they don’t specify by how much.

Even though it is clear that cooking in cast iron can be a tool to enrich your diet, sources all emphasize that using this cookware is not a notable enough source of iron to replace dietary changes and supplements if you are iron deficient. 

Dr. Federica Amati, PhD, MPH, RNutr, and Head Nutritionist for Zoe says that “cooking in cast iron is generally viewed as a supplemental method for increasing iron intake rather than a primary strategy. It is most beneficial for individuals who are slightly low in iron or looking to maintain healthy iron levels. For individuals with diagnosed iron deficiency or anemia, cast iron cooking alone is not going to provide enough iron, and additional dietary modifications or iron supplements may be necessary.”

It’s also worth noting what type of iron you’ll absorb from employing this material in the kitchen. Toby Amidor, MS, RD, CDN, award winning nutrition expert, and Wall Street Journal best selling author of Health Shots explains that when you’re utilizing cast iron cookware, “the type of iron being absorbed is called non-heme iron, which is the iron typically found in plant foods like leafy greens and beans. Non-heme iron is more difficult for the body to absorb (it doesn’t get absorbed as efficiently) than heme iron from animal foods (like beef and chicken).”

The amount of the nutrient that these tools can add to your meals might be much more significant if you have too much iron in your body. If that’s the case, you should consult your doctor about whether or not it’s safe for you to cook with cast iron.

How can you use cast iron to add more iron to your diet?

You don’t need to cook in your cast iron skillet every day to take advantage of the metal. Instead, Amidor recommends “cooking with cast iron once or twice a week, especially if someone has iron-deficiency anemia and no issues with too much iron in their diet.”

Preparing a more acidic dish, or something with a lot of moisture, is likely to absorb more iron from your pot or pan. Acidic foods include anything tomato-based (like shakshuka or a baked pasta with tomato sauce), citrus, and alcohol (a lemony white wine sauce would combine the best of both worlds). And a dish with moisture is easy to find — just simmer any soups, stews, or a skillet full of chili. The longer you cook these ingredients and dishes in your cast iron, the more of the metal they’ll absorb.

Of course cast iron aficionados know that these same foods are also what removes seasoning from your pan. This doesn’t mean you can’t cook them in cast iron, but it does mean you can’t make them all the time — simmering tomato sauce in a cast iron dutch oven needs to be interspersed with cooking recipes that will add seasoning to the pot’s surface too, like anything deep-fried. Luckily, research confirms that even cooking in a well-seasoned cast iron pan will still add some iron to the food, but issues with seasoning are just another reason why you shouldn’t rely on these tools as the sole method for boosting your iron intake.

Are there other ways to add iron while you’re cooking?

If you’re worried about that precious seasoning on your cast iron skillet, or simply don’t like the extra care needed to own and use these pots and pans, another easy option that will yield similar benefits is to incorporate an iron ingot into your cooking. Research shows that this has advantages similar to those of preparing meals in cast iron.

The most common way to do this is by employing a small iron fish! These are cute little fish-shaped ingots of iron, which you can find at online retailers like Amazon. Research published in 2017 notes that “clinical tests have shown that daily use of the Lucky Iron Fish can restore circulating and stored levels of iron…” To get a more meaningful amount of iron into your food from the fish, you’ll need to simmer it in liquid. For example, add the small accessory to a pot of boiling pasta water, some rice while it steams, or a simmering sauce. Just like cooking in cast iron pans, using acidic ingredients will allow you to reap even more iron from the small ingot.

It’s helpful to think of cooking in cast iron as a tool for enriching your diet with an important mineral, as opposed to a complete solution. For someone like me who owns five cast iron skillets, I’ll certainly be busting them out when I notice I’ve been neglecting to eat foods rich with the nutrient — and I’d recommend you do the same.

But if you’re concerned about your iron levels or already know you have a serious deficiency, work with your doctor to determine a reliable and long-term strategy for ensuring you have enough of it in your system.