Dr. Universe,

Why do we need to eat and drink?

— Victoria, 7, Minnesota

Just like a car needs gas to run, food is the body’s fuel. Food gives us energy, or the power to do work. It helps us run, jump, think and do all kinds of things.

That’s what I found out from my friend Alice Ma, a dietitian at Washington State University.

When you take a bite of food it goes down your throat, or esophagus, and down into your stomach. In the stomach and small intestine, things like bile, acid, and enzymes help digest, or break down your food so your body can absorb the parts it needs.

Food also contains carbohydrates, a substance rich in energy that is made up of carbon, hydrogen and oxygen.

Carbohydrates can give us a lot of energy, especially when they come from foods like grains, pasta, rice, veggies, breads, legumes and nuts.

Here’s how it works: the body breaks down carbohydrates into simple sugars, which get absorbed into your blood.

Sugar levels rise and your pancreas — an organ down on the right side of your belly — releases something called insulin, which helps move the sugar into your cells. Your cells can now use the sugar to produce energy, or store the sugar for later use.

There are all kinds of different foods to try in our world. One of Ma’s favorite ingredients is peanut butter. She likes to put it on top of her pancakes, cook it into curry, and dip spring rolls into a peanut butter sauce.

“I cook a lot of different things,” Ma said. “I’m always experimenting.”

She said one question she also gets is, “What would be the one good food to take with you if you were stranded on a deserted island?”

“There’s not one single food that everyone can eat to power everything,” she said. “You need a variety of foods.”

Food also contains lots of different parts, such as vitamins and minerals, that get absorbed as digestion happens. Protein from foods like meat and peanut butter get stored in muscle, skin and other tissues and organs. Calcium from things like cheese or green leafy veggies can help the heart pump and keep bones strong.

As a dietitian at WSU, Ma helps plan and create meals that fill the bellies and power the brains of thousands of university students. She also encourages people to drink plenty of water.

Water is important to our cells, along with our organs and tissues. In fact, water is what makes up most of our blood. Blood helps carry things like oxygen and nutrients through our body.

We lose a lot of water everyday through things like breathing, sweating, and going to the bathroom. That’s why it is so important to drink water every day.

While food and drinks are important to our health, they are also a big part of culture. Humans celebrate entire days about food and throw festivals to appreciate different cuisines. What kinds of foods do you celebrate in your family? Tell us about it sometime at Dr.Universe@wsu.edu.

P.S. If you or someone you know needs access to food or wants to donate to a food bank, search the Food Finder for more information: foodfinder.us/

Have a science question? Ask Dr. Wendy Sue Universe, WSU’s resident science cat and writer, by email at Dr.Universe@wsu.edu.

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