Do "iron fortified" cereals really contain iron filings?

Dear Cecil: I saw a chemist’s demonstration where a bowl of Total cereal was soaked in hot water (to dissolve the cereal). Then a white magnet was placed in the solution. Upon removal, the magnet was covered with tiny specks of metal, apparently iron. A white magnet placed into a packet of “iron fortified” instant oatmeal and shaken around will also come out covered with tiny iron filings. Are these filings actually nutritious, or is this some terrible joke so these products can claim to be “iron fortified”? William B. Stockton, Washington, DC

Cecil replies:

Let’s think about this, William. The stuff says “iron fortified.” Experiments show it IS iron fortified. You figure this is some kind of deceitful practice? Like maybe it should say, “iron fortified and WE MEAN IT”?

Get with the program. Different iron compounds are used in different products and the particles may be different sizes, all of which affects how “biologically available” the stuff is. But yes, when a product says “iron fortified,” that often means they put iron filings into it.

Let me add that the filings are tiny, on the order of a few dozen microns in diameter. The particles can range from straight powdered iron (“reduced iron”) to compounds such as ferrous sulfate and ferric phosphate.

The stuff is “harmless and assimilable,” it says here, and your body definitely needs it. Iron deficiency is common in the U.S. At one time the Food and Drug Administration even considered asking that higher levels of iron be added to more foods. (The plan died because of fears that more iron might trigger certain rare diseases.)

So eat, William. It’s good for you. Just don’t try walking through a metal detector afterward. For more information on iron and other food additives, read The Complete Eater’s Digest and Nutrition Scoreboard by Michael Jacobson (1985).

Cecil Adams

Send questions to Cecil via cecil@straightdope.com.