Eating Nails - Iron for Breakfast
The next time you're eating a big bowl of breakfast cereal, take a closer look at the ingredients. You'll find that your cereal contains more than just wheat and corn. Look closely and you might find iron... you know, the metal... the stuff used to make nails. Here's an experiment to see if there really is metallic iron in your breakfast cereal.
- Box of iron-fortified breakfast cereal (Total works well)
- Measuring cup
- Super strong magnet
- Quart-size zipper-lock bag
- Dinner plate
- Open the box of cereal and pour a small pile of flakes on the plate. Crush them into tiny pieces with your fingers. Spread out the pile so it forms a single layer of crumbs on the plate. Bring the magnet close to the layer of crumbs (but don't touch any) and see if you can get any of the pieces to move. Take your time. If you get a piece to move without touching it, that piece may contain some metallic iron.
- Firmly press the magnet directly onto the crumbs but don't move it. Lift it up and look underneath to see if anything is clinging to the magnet. Several little pieces may be stuck there. Is it the magnet being attracted to static electricity or just sticky cereal? It could be the iron. Throw away the small pile of cereal and clean off the magnet.
- Pour water into the plate and float a few flakes on the surface. Hold the magnet close to (but not touching) a flake, and see if the flake moves toward the magnet. (The movement may be very slight, so be patient.) With practice, you can pull the flakes across the water, spin them, and even link them together in a chain. Hmmm... there must be something that's responding to the magnet. Could it be metallic iron? In your cereal?
Cereal Soup: Now With Iron!
- It's time to mix up a batch of cereal soup to further investigate the claim of iron in your breakfast cereal. Measure 1 cup of cereal (that's equal to one serving according to the information on the side of the cereal box) into a quart-size zipper-lock bag. Fill the bag one-half full with warm water. Carefully seal the bag, leaving an air pocket inside.
- Mix the cereal and the water by squeezing and smooshing the bag until the contents become a brown, soupy mixture. Allow the mixture to sit for at least 20 minutes.
- Make sure the bag is tightly sealed and position it on a flat side in the palm of your hand. Place the super-strong magnet on top of the bag. Put your other hand on top of the magnet and flip the whole thing over so the magnet is underneath the bag. Slowly slosh the contents of the bag in a circular motion for 15 or 20 seconds. The idea is to attract any free moving bits of metallic iron in the cereal to the magnet.
- Use both hands again and flip the bag and magnet over so the magnet is on top. Gently squeeze the bag to lift the magnet a little above the cereal soup. Don't move the magnet just yet. Look closely at the edges of the magnet where it's touching the bag. You should be able to see tiny black specks on the inside of the bag around the edges of the magnet. That's the iron!
- Keep one end of the magnet touching the bag and move it in little circles. As you do, the iron will gather into a bigger clump and be much easier to see. Few people have ever noticed iron in their food, so you can really impress your friends with this one. When you're finished, simply pour the soup down the drain and rinse the bag.
How Does It Work?
Many breakfast cereals are fortified with food-grade iron particles (metallic iron) as a mineral supplement. Total® cereal is the only major brand of cereal that claims to contain 100% of your recommended daily allowance of iron. The chemical symbol for iron is Fe. Metallic iron is digested in the stomach and eventually absorbed in the small intestine. If all of the iron from your body was extracted, you'd have enough iron to make only two small nails.
Iron is found in a very important component of your blood called hemoglobin. Hemoglobin is the compound in red blood cells that carries oxygen from your lungs so that it can be utilized by your body. It's the iron in hemoglobin that gives blood its red appearance.
A diet deficient in iron can result in fatigue, reduced resistance to diseases, and increased heart and respiratory rates. Food scientists say that a healthy adult requires about 18 mg of iron each day. So, as you can see, iron is a very important part of what you and your friends and family need to stay healthy. Eat up! Cereal for dinner!
Science Fair Connection:
A good science fair experiment must include a variable, or something that changes in the experiment. If you are only trying to find iron in one type of cereal, you don't have a variable. You are merely demonstrating that the cereal contains iron.
- Choose several cereals and follow the same procedure as above to see which cereal contains the most iron.
Be sure to use the same amount of cereal, the same amount of water, and the same magnet in your tests so that you standardize the conditions as much as possible and isolate the variable, which in this case is the brand of cereal. Document your results and get ready to share your discoveries at the science fair.
- Is it Useable Iron? Review by Robert
What is not mentioned here is that Iron comes in different forms. The metal shavings in the cerea are, in fact, a form not useable by the human body.
In WWII (World War II) POWs would suspend iron nails in water so tey would rust. Iron Oxide (rust) IS absorbed by the body. Smelted iron (like the nails and te shavings) is not.
Very interesting information! We aren't making any claims as to the health benefits of the iron in the activity. Instead, we're just using the iron's presence as a way to make science exciting and fun! Thanks for your comments!
- Steve Spangler Science Web Team
(Posted on January 19, 2013)
- Wow! Review by Robyn
This was a fun experiment - I can't believe how well it worked!
(Posted on May 29, 2012)
- Fooled by the cereal charlatans Review by Luke M.
As an experiment, it is nice. It tells us how to look for metallic iron in our foods. In other words: it tells us how to spot an absurdity, something that does NOT belong there, does NOT do anything for our health and is put there by people who know all this perfectly well, but see it as the cheapest way to add health claims to a simple cereal. In Denmark and other counties where they do care about public health, adding metallic iron is forbidden. In your explanation, you do claim that the iron 'will be resorbed in the small intestine'. That's not true and it sounds like you condone the practice of adding useless junk to children's food.
Great observations, and you're right, this experiment is largely intended as an engaging experiment for elementary-age children. You're also right about elemental, or metallic, iron being nonabsorbable by the human body. However, elemental iron reacts with hydrochloric acid in the stomach (stomach acid) to create ferrous iron, which is absorbable in the small intestine. Thanks for the feedback, and keep experimenting!
- Steve Spangler Science Web Team
(Posted on January 27, 2013)
- Netherlands - TV item Review by Vicje
Within The Netherlands there once was discussion after a television item about iron in cereals. They claimed the iron is from old bicycles and stuff.
(Posted on January 27, 2013)
- Really cool, but have questions Review by Allison D
This worked great with Total and some other cereals with high iron content. If it had less than 75% RDA iron, I couldn't get it to work, with the exception of Krave which had only 25% RDA of iron, but had noticeable iron shards in it. That was puzzling! I tried dissolving a multi-vitamin that has 100% RDA of iron (in the form of ferrous fumarate) and couldn't get anything to stick to the magnet. I am wondering if different cereals (or vitamins) have different types of iron in them. Are some of them, like ferrous fumarate, not magnetic?
That's a great question and definitely something to investigate further. We only intend the demonstration for elementary education purposes, so to go deeper into the science, you'll be blazing the experimental path. Good luck, and keep experimenting!
- Steve spangler Science Web Team
(Posted on April 4, 2013)
- Awesome Science Fair Project Review by Debbie M.
I bought this magnet 3 years ago for my son in 6th grade. He had a science fair project to do for end of the year. He surprised the judges and he won 1st place over all. Now my youngest son in 4th grade is having his science fair and he will be doing the same project.
(Posted on December 13, 2010)