Vol.38 What is the most effective way to take in iron?

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Do you think that the iron content of liver and spinach is all the same?

There are two main types of iron: divalent iron and trivalent iron.

Divalent iron is found mainly in animal foods such as liver and is a type of iron that is easily absorbed.

Iron (III) is found in large amounts in plant-based foods such as vegetables, and is a type of iron that is difficult to absorb as is.

When trivalent iron is taken with vitamin C or other substances, it is reduced to divalent iron in the body and then absorbed.

The iron that dissolves from ironware becomes ferrous iron.
This means you'll get some iron every time you cook.
However, in order to obtain the daily required amount of iron just from the iron that dissolves in ironware, you would have to eat a huge amount, so it should only be considered as a supplement.
Iron is weak against acid, but cooking with acidic ingredients will increase the amount of iron dissolved (such as miso soup or stewed tomatoes). However, it is easy for rust to form, so do not leave it with food in it for a long time.

Our ductile iron series changes the iron itself into iron that is resistant to rust, so the amount of iron that dissolves is inferior to that of ironware, which rusts easily.

Therefore, we recommend "iron eggs" to get more efficient iron intake!
To use it, simply place the iron egg in a pot of boiling water, remove it when the water boils, and wipe off the water.

The human body cannot produce iron, so if you do not actively consume it, you will become anemic. Women in particular need iron, so in addition to getting it from food, we also encourage the use of iron kettles and iron eggs.

Some people may have heard that adding an iron nail to boiled black beans will improve their color. The anthocyanin contained in black beans dissolves easily in water, and if they are boiled as is, the color will fade.


By adding iron nails or iron eggs to the water and boiling it, they react with the anthocyanin and cause the color to come out beautifully.
The nasunin contained in eggplant also reacts with iron to give it a beautiful color, making it a great choice for pickling.

The relationship between humans and iron is ancient and it remains an indispensable part of our lives today, but I think the frequency with which iron cookware is used is decreasing.

I would be delighted if you become interested in ironware and take a new look at it.
Thank you for your continued support.