Wouldn't iron be the best at least for pans? Also what about enamel?
Fortunately, excessive quantities of iron in food are not dangerous for most people, even when the quantity is great enough to give an unpleasant taste to the cooked food.
In any case, iron cookware is preferable to ceramic/plastic/non-sticking cookware of unknown chemical composition.
All colored enamels have undesirable components.
White enamel can be made perfectly safe for food contact. Unfortunately, being white is not a guarantee for that.
Manufacturers are tempted to include in the enamel composition various oxides that improve the manufacturing properties, e.g. which increase the fluidity of the melted enamel, or which enhance the adherence of the enamel to the base metal, and so on. These additives may leach unwanted substances.
So one may use cookware with white enamel, if they trust that the manufacturer was not too greedy to reduce their costs.
Ideally there should be a law to force all manufacturers of cookware to publish the precise chemical composition of any material used for food contact, like there are laws for labels with the approximate food composition.
Until then, it is safer to distrust any kind of coatings, plastics, enamels or glazes with secret compositions, because in the past there were many bad surprises whenever any of these were analyzed.
Once your iron gets into contact with oxygen, you will no longer consume iron, you will consume rust...
Metallic iron cannot be used in any way by living beings, before it is oxidized to rust.
The leaked iron from cookware is already in the form of "rust", more precisely the iron is leached after it is oxidized to iron ions. The ions with 2 elementary charges remain dissolved in the water, and they may be absorbed by the body, while the iron ions with 3 elementary charges (these are the components of rust in the strict sense, i.e. of red iron oxide) will normally precipitate into red rust crystals, which will pass through the digestive tract mostly without being absorbed (a few might be reduced to ions with 2 charges, and then be absorbed).
https://www.bbc.co.uk/news/health-32749629
You can buy them in the west now (even on Amazon I think):
It should also be noted that with a properly seasoned cast iron pan, the food isn't interacting as much directly with the iron, since the seasoning layer (polymerized fats) is in the way.