Why is there iron in my cereal? Is there iron in other food? –Phillip, 11, Pullman, WA
Dear Phillip,
Iron is found in buildings and skyscrapers. It makes up most of the Earth’s core. It’s even found in the Sun and stars. And yes, it’s also in a bowl of cereal.
In nature, we might find iron in a black and steely mineral form buried deep in the earth. But right in our bodies, we also find iron in blood.
That’s what I found out from my friend Brennan Smith when we set out to investigate why there’s iron in cereal and other foods.
Smith is a professor of food science who teaches students at Washington State University and the University of Idaho. He explained that iron is in cereal and other foods for our nutrition. I wondered exactly what it does for us.
Smith explained that in your blood you have something called hemoglobin, which gives your blood its red color. Hemoglobin also helps carry oxygen through your body. But it can’t do this without the help of iron.
Iron helps bind the oxygen you breathe to the hemoglobin. The hemoglobin holds onto the oxygen and carries it through your body to help you stay strong.
“That’s one of the most important reasons why we have iron,” Smith said.
Without iron, you might start feeling weak and tired because your body isn’t getting enough oxygen. But eating foods with the right amount of iron helps you grow, think, and play.
My friend Jen Hey, another expert in nutrition here at WSU, said good sources of iron are eggs, beans, some kinds of shellfish, and meat. Mmm, I was starting to get hungry. There’s also iron in tofu, dried fruit, and dark, leafy green vegetables.
The plants farmers grow to make cereal grains also need iron, too. These plants use iron to help carry oxygen, just like in people. And without iron, they wouldn’t be able to make their green colors.
A lot of plants and animals naturally have a lot of iron. Sometimes there are foods that are fortified, and iron is added to give it a boost.
It depends on what kind of cereal you are eating, but usually there is a small amount of iron combined with other ingredients. Just read the label and you’ll find out about things like zinc, calcium, and vitamins.
From the stars in outer space to plants in a field to the cereal in your bowl, iron is an important element in our universe. Iron is a kind of metal. Metals can also be magnetic. Iron is magnetic, too. That’s why you can grind up some cereals and get the iron out with a magnet.
There might even be some iron in the metal spoon you use to eat your cereal in the morning.
If you like food and science, perhaps you might want to be a food scientist one day, Phillip. In fact, with a question like this one, you are well on your way.
“Keep asking lots of questions,” Smith said. “Always be asking questions.”
Sincerely,
Dr. Universe
What is the Kuiper Belt? -Zaara, 7, Deep Bay, Australia
Dear Zaara,
You might say the Kuiper Belt is the frozen frontier of our solar system. Out beyond Neptune’s chilly orbit, this saucer-shaped region is home to Pluto, billions of comets, and other icy worlds.
“The Kuiper Belt is really the edge of knowledge,” said my friend and astronomy professor Guy Worthey when we met up in the Washington State University planetarium.
“Out there it’s a little dim,” Worthey said. “We are pretty far from the Sun.”
In fact, it’s about 3 billion miles away. Even at the speed of a jet airplane, it would take more than 680 years to travel from Earth to the outer solar system. Fortunately, spacecraft like NASA’s New Horizons can get there much faster.
Just last year, the world watched as New Horizons flew past Pluto and sent us the first up-close pictures of the dwarf planet. Now, it won’t be long before we head even deeper into the Kuiper Belt.
“Everything is going to be dark,” Worthey said. “But you’ll see these icy bodies. They’ll be of different sizes. There’ll be lots of little ones and some big ones.”
Many astronomers think there are 100,000 objects out there bigger than 60 miles wide, Worthey adds.
“They are sort of a dirty snowball composition,” Worthey said.
Just 15 years ago astronomers weren’t really sure if this part of the solar system even existed.
In the 1950s, Gerard Kuiper (KI-purr), a Dutch astronomer, was curious about comets, particularly where they were coming from and how they traveled through the solar system. He thought the outer solar system just couldn’t be empty.
About 40 years later, two scientists working at an observatory in Hawaii detected the first object in the Kuiper Belt aside from Pluto and its moon Charon. They had been looking for five years when they finally found an ice sphere more than 150 miles wide.
Ever since, astronomers have been using math and science to detect other distant objects. They’ve detected other dwarf planets like Pluto, including Eris, Haumea, and Makemake.
They’ve also found Plutinos that, like Pluto, are small worlds that have been caught in Neptune’s orbit.
“As you cruise by one of those things, they’ll look like spheres or worlds,” Worthey said. “They are quiet, they are on slow orbits.”
Astronomers are fascinated with these places for a couple of reasons. One is because the region may hold clues about the way solar systems form. Other scientists are particularly interested in the comets. Some wonder if some of these icy objects fell from the Kuiper Belt, and then melted in the Sun’s heat to form Earth’s oceans.
There’s also been a buzz about finding a new ninth planet in the Kuiper Belt or beyond. Though, there’s no proof of it yet, it’s an exciting prospect. If there is another planet in the Kuiper Belt, we’ll have to go find it with a spacecraft or a super huge, powerful telescope.
Sincerely,
Dr. Universe
