So many people tend to boil liquids like water and sauces in their cast iron cookware. But is it safe to do?

The short answer.

You can boil water and liquids in your cast iron without any issues. It will not ruin the seasoning or create rust. For example, I simmer sauces and I use boiling water to clean my cast iron skillet. As long as you don’t soak it for long periods, your cast iron will be OK.

Why do some people say you shouldn’t boil water in cast iron?

There’s an old age myth. Suppose you boil water or any liquids in cast iron. In that case, you will cause the seasoning on your cast iron to break up and eventually flake off, which will ultimately expose the cast iron to the air and accelerate rusting.

The truth? I’ve been doing this for years, and my seasoning is still going strong. So there is no problem with doing this at all. Furthermore, since my seasoning is OK, there is no rust on my cast iron skillet.

Why the confusion?

There are two reasons that the seasoning will flake off after boiling liquids in cast iron.

The first is, people are boiling acidic liquids such as tomato sauce. If you didn’t already know, anything acidic will eat away at your seasoning and cause it to flake off. Probably one of the main reasons for the myth of boiling water in cast iron being so popular in the first place.

The second is, people are not seasoning their cast iron properly. We wrote a fantastic guide on how to season cast iron cookware. If you do it properly and avoid acidic foods and sauces, your seasoning will stay strong.

Suppose you don’t season properly, like adding too much oil to the seasoning process. You’ll end up with seasoning that’s not fully bonded to the cast iron surface. The result? It flakes off during cooking, especially with liquids with acidity.

So it’s OK to boil water and liquids in cast iron?

Yes, it’s OK. Most people want to know if they can use boiling water to clean their cast iron skillet.

You can, not a problem, as long as you don’t leave it to sit in the boiling water too long, it’s OK. Always remember to dry thoroughly, too, after cleaning with water as prolonged exposure will cause rust.

As for cooking with boiling water or liquids, this is OK to do. I probably wouldn’t go as far as using a cast iron pan for boiling pasta for 20-30 minutes at a time. Although I have not tried this, I’m OK with using my cast iron skillet to reduce sauces.

Seasoning is the barrier between your cast iron and the food. As long as you have good seasoning, you have an excellent protective barrier. Your cast iron is entirely safe.