Put kosher salt in a cast iron skillet: Why Good Housekeeping recommends it for removing burnt food residue

There are some things that get better with age. A cast iron skillet is one of those things, as long as you know what not to clean it with. Cast iron is an old cooking staple; it is durable and likely to outlast many kitchen trends. There is one problem, however: with time, after rounds of searing, frying, and roasting, even the most seasoned cast iron skillets get bits of burnt food etched on their surface. And all of a sudden, cleaning up turns into a tug of war between the sponge and the pan.

Luckily, there is a solution that does not involve purchasing any special chemicals or expensive products. According to Good Housekeeping's 2025 guide to cleaning and reseasoning a cast iron skillet, there is a rather surprising product that can help you remove food stains from it. As Nicole Papantoniou, director of the Kitchen Appliances and Innovation Lab of Good Housekeeping, says, a thin layer of kosher salt as an alternative to dish soap can do the trick. Unlike the earlier myth that soap must not come into contact with your cast iron, the Good Housekeeping Institute experts note that mild dish soap and warm water are also fine to use; however, the skillet should never be left soaking in water or put in the dishwasher, and it should be dried thoroughly after washing.

Why salt and not steel wool


This is where logic finally kicks in from a scientific perspective rather than a superstitious one. Cast iron's seasoning is basically a polymerized cooking oil layer cooked into the metal, and it's highly vulnerable to anything that is harder than itself. Steel wool and scrubbers made of abrasives are both harder than iron and therefore manage to literally scrape off that layer, which explains the rough appearance of your cookware after some harsh scrubs. Kosher salt does its job thanks to being the exact opposite: it is soft.

According to a Geology.com article by PhD scholar Hobart M. King, on the Mohs hardness reference, halite, which is a mineral form of salt, lies within the range of 2-2.5, whereas iron has the range of 4-4.5 on the Mohs scale. The Mohs scale is a relative measure of scratch resistance, and the hardness of common metal objects can vary considerably. Kosher salt, meanwhile, is coarse enough to provide friction while being used as a traditional cleaning aid for cast iron. Good Housekeeping specifically recommends coarse salt because it can help preserve the pan's patina and reduce how frequently it needs to be reseasoned.

The actual method

Good Housekeeping's salt method is slightly different from the one described above. First, pour out any food bits or drippings and add a thin layer of kosher salt to the inside of the skillet. Then, on the stovetop, use a wooden spatula to scrape away stuck-on food and burnt bits. If the residue is particularly difficult, heat the skillet slightly while scraping to help loosen it. Once the pan is completely cool, discard the salt and wipe the skillet clean with a paper towel or cleaning cloth.

The overlooked upside: a little extra iron in your food

There is a nutrition-related aspect to all this focus on cast iron pans that may be a little rarely talked about except among dietitians. While cooking with iron cookware does not entail the risk of leaching nutrients from the utensil, it may also result in a very quiet addition of small amounts of dietary iron into whatever is being cooked. Indeed, as described in an old study titled “Iron content of food cooked in iron utensils,” from 1986 by Brittin et al., in the Journal of the American Dietetic Association, approximately 90% of the 20 examined foods accumulated more iron from the iron utensils than from the non-iron ones, while the highest iron accumulation was observed in acidic and moist foods such as tomato sauce and applesauce.

In a 2021 systematic review titled “Effect of cooking food in iron-containing cookware on increase in blood hemoglobin level and iron content of the food: A systematic review,” published in the Nepal Journal of Epidemiology, some studies showed an increase in blood hemoglobin levels through routine usage of iron cookware, although the results greatly differed across the populations studied and were not consistent across all the studies. There is no headline asking you to substitute multivitamins for cast iron pans, especially considering how careful the researchers themselves were with their conclusions, but it is a bonus to keep in mind when treating the pan as the king of your pantry.

What not to do

Don’t allow the pan to soak, don’t put it in the dishwasher, and don’t forget the oiling phase even if you’re in a rush. Without proper protection, an untreated pan will begin to rust within hours of being left wet. If you have a particularly stubborn pan that’s been neglected for years and has a really thick buildup, then don’t count on mere two tablespoons of salt to reverse years of damage in just one cleaning; more intensive cleaning might actually call for a proper reseasoning rather than simple scrubbing. However, when done correctly, it isn’t only a “kitchen hack” but rather a return to a traditional method of cleaning cast iron cookware, before people started spending $12 on specialized cleaners for a $30 pan. Sometimes your kitchen shelf may be hiding the answer.