There are many benefits to cooking in cast iron. Some of the biggies include more even heat distribution, stovetop-to-oven cooking, and a reliably gorgeous sear. But we’re often told that cast iron cooking has health benefits — is this really true? I’ve operated under this assumption for over a decade, ever since a diagnosis of minor anemia; my doctor reviewed my blood work and suggested that I start cooking meals in cast iron with the idea that the iron in the pan would naturally transfer to the food, which I’d then, of course, eat.

I’ve been cooking in cast iron ever since, but lately I got to wondering: Are the health claims true? Are there real health benefits to cooking in cast iron versus other types of cookware? Or is it all a load of hooey? Let’s take a look.

What exactly is cast iron?

Before we get into the science of it all, let’s define what a cast iron pan actually is.

Cast iron cookware is made from iron (shocking, I know). Most cast iron cookware is made by melting a combination of iron ore and steel at super-high temperatures (we’re talking in the realm of 2,500-3,000 degrees Fahrenheit!). The metals are bonded together and shaped with molds, then typically sandblasted to remove any impurities. These pans are prized because iron is an incredibly dense material — more so than aluminum or copper, for example — and as a result, have great heat-retention qualities.

For the purpose of our discussion today, when we talk about cast iron, we’re talking about the bare variety. This means that food has direct contact with the iron pan, and differs from enameled cast iron, which is lacquered with a food-safe glaze. The glaze makes cleanup easier, and acts as extra nonstick insurance, although, of course, the glaze is not made of iron.

But does that actually matter? Are you gaining health benefits from bare cast iron? Are you losing them when you use enameled cast iron? And why is iron so important, anyway?

Why our bodies need iron and how we get it

Iron is both a material and a mineral. In its mineral form, iron aids in the production of hemoglobin (necessary for red blood cells), as well as hormones. While iron is naturally occurring in many foods, some humans are deficient due to diet, or under-nourishment. Anecdotal evidence here: When I received my anemia diagnosis, I was eating a vegetarian diet and not paying much attention to replacing the iron I would have otherwise been consuming with red meat.

There are two types of iron, heme and non-heme, and both occur naturally in foods. It’s important to note that heme iron, which occurs in animal protein, is more readily bioavailable (processed by our bodies). Non-heme iron relies on other nutrients, namely Vitamin C, to aid in absorption.

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