How much iron is there in breakfast cereal? Is it the same sort of iron that might be used in steel?


Take care using the magnet – neodymium magnets are extremely powerful and can pinch fingers if used without caution.

You will need

  • breakfast cereal high in iron (Special K or Nutri-Grain are suitable)
  • plastic bag and rolling pin, mortar and pestle, or a food processor
  • large bowl
  • measuring cup
  • fork
  • water
  • white balloon
  • magnet (large neodymium magnets work the best, and are available at most hobby stores.

What to do

  1. Robots can be made of many materials, steel being one of them. Complete the activity to find what Robots eat for breakfast

    Pour approximately 4-5 cups of cereal into the plastic bag, food processor or mortar. Whiz, bash or thump the cereal until it is as fine as you can make it.
  2. When you are satisfied the cereal is finely ground, empty it into the bowl.
  3. Pour enough water into the bowl to cover the cereal completely, and leave it sit for 10 minutes. The cereal should soak up the water.
  4. Pour more water into the bowl until the cereal is floating in it. Stir the mixture and use a fork to mush it up more.
  5. Push the magnet into a white balloon and tie a knot in the balloon to hold the magnet firmly in place. The balloon will help keep the magnet clean, while the white colour will help you see the iron clearly.
  6. Stir the magnet slowly through the cereal mixture, making sure to run it along the bottom where the iron will have sunk. Be patient, especially if it is a weak magnet. It will take some time for the magnet to pick up enough iron for it to be visible.
  7. Remove the magnet every now and then and have a close look. If you need, carefully dip the magnet into some clean water to wash off the bits of cereal. The iron should look like a dark stain against the white rubber of the balloon.

What's happening

Breakfast is undoubtedly an important meal. After eating nothing substantial since dinner, your body needs energy to go out and start the day.

Cereal is a rather useful breakfast food. Made from the seeds of grasses, they are usually packed with complex sugars (better than simple sugars which break down quickly) which provide sustained energy. So long as they aren't refined too much, they should also still have fibre from the outsides of the seeds. Unfortunately some producers add more simple sugars for sweetening, or add salt for flavour.

Seeds aren't usually packed with all the nutrients your body needs. There are some vitamins, minerals and protein, but our bodies require much more. Some companies will therefore also add extra nutrients. Folate is one example, and iron is another. As you've just seen, this iron is in the exact same form you'd expect to find in a crowbar or a building's steel beams. Your diet requires diverse foods to supply you with many different nutrients.

Next time you're choosing cereal, look at the nutrients on the side of the box and think about whether it is giving you what your body needs.

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