Cast iron cookware: Will it affect your iron levels?

Can cooking in cast iron cookware help your iron levels? Our Registered Dietitian, Katrina Dixon investigates the science behind this popular theory.

There’s plenty to love about cast iron cookware; it’s built to last, is incredibly versatile, and can add a unique, delicious flavour to your food when seasoned and cared for. You may have heard that cast iron cookware can also work wonders for your iron levels too. The theory is that iron from cast iron cookware can be transferred into the food which is then eaten, digested, and absorbed. It sounds plausible, but what does the science say?

The simple answer is the research is mixed; there’s research for and against it helping iron levels. In essence, cooking with cast iron can transfer a variable amount of iron to your food (emphasis on the word ‘variable’). There is some evidence to show that iron levels can increase after using cast iron cookware for a period of time, as a combined approach with increasing iron-rich foods. However, these findings have mostly been shown in those who have extremely low iron levels to start with, such as women and children in developing countries. Ultimately, the science isn’t concrete and the main reason is because there are many factors that can influence the amount of iron that you can absorb, let alone from cast iron cookware.

Let’s start with what can influence iron absorption in general. The list is long and includes:

Your current iron status (if your body needs more, you will absorb more and vice versa)
The amount and types of iron-rich foods you eat (e.g. haem iron or non-haem iron sources)
Whether you eat iron enhancers (e.g. vitamin C or meat/seafood/poultry with plant-based iron sources) and/or inhibitors (e.g. tea and dairy foods). For more information click here.

As you can see, iron absorption is complicated without cast iron cookware thrown in the mix. When it comes to the amount of iron that could be transferred from cast iron cookware to food, there are also several factors that could influence this. For example:

How often the cookware is used. If you use your cookware once in a blue moon it won’t have any effect on overall iron status
The size of the cookware with the bigger sized pan/wok/pot having a larger possible effect
The type of food cooked. For example, acidic and moist food have been shown to absorb more iron
How long food is cooked for with the longer the cooking time showing a more favourable effect
The age of the cookware and degree of seasoning with older and more seasoned cookware potentially having a lesser effect.

The bottom line is that under certain conditions cast iron cookware can provide a small amount of extra iron to food, but there are a lot of barriers to this happening and there are no promises that it necessarily will – to date most studies from developing countries have seen variable results. Therefore, cast iron cookware is by no means the silver bullet to resolve or treat low iron levels, but rather it should be used as a versatile, durable, and fantastic cooking tool.

In a nutshell, it’s what’s cooking in the cast iron pan that can have the larger effect on iron levels rather than the pan itself. It's no secret that the natural way to get iron in the diet is through iron-rich foods, such as red meat, poultry, seafood, silverbeet, lentils and fortified products (such as cereals). Upping the ante with these foods is a good first line approach to increase iron levels, however if you’re experiencing any signs or symptoms of low iron be sure to visit your GP and get your iron levels checked. Medical advice from your GP, as well as nutritional advice from a Registered Dietitian or Registered Nutritionist is recommended to combat iron deficiency and iron deficiency anaemia.

While your cast iron pan might not affect your iron levels, it can deliver so many other awesome benefits that should not be overlooked – check out our other blog on the benefits of cast iron cookware. If you’re feeling inspired to dig out your cast iron pan from the bottom of the cupboard, or to buy your first ever one, we’ve got the perfect recipes for you try. Just click on one of these delicious recipes below or visit our recipes page which has these and our others from our friends at the Iron Clad Pan Company. To learn about whether cast iron cookware can affect your iron levels click here.