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Nutrition: Facts

Why You Need Food


Nutrition is the science or study of how your body uses nutrients. Just like a car, your body needs fuel to work properly. The food you eat contains substances called nutrients that provide the energy (fuel) for your body to make new cells, heal, fight illness, grow, play and work.


Here are the 6 kinds of nutrients that provide your body with what you need to think, play and work properly.


Proteins are used by the body for growth, and to help build and repair cells. Proteins also help keep muscles, skin, hair, and nails healthy.


Carbohydrates are the main source of energy for your body. Some carbs like sugar give you quick energy. Other carbs such as starches give longer lasting energy.


Fats and Oils are used to help the body store vitamins and build tissue to protect important organs. Fats are also used by the body as a "backup" fuel system.


Vitamins are needed to help the body use carbohydrates, fats and proteins and to help its systems function. Many kinds of vitamins are essential to your diet.


Minerals are used by the body to build new cells and control important body processes.

water glass

Water dissolves some vitamins and helps bring nutrients to the cells in your body. Water also helps you swallow and digest foods, and helps keep your body temperature normal.




There is no single food that can supply all the nutrients your body needs to stay healthy. That's why it's important to include a variety of foods in your diet!

DIET? I'm Not On a Diet!

eating pizza

Think again! Your diet is everything you eat and drink. The question is — is it a healthy or unhealthy diet? A healthy diet is a balanced diet that includes healthy portions from all of the food groups.

The Food Pyramid Guide has been changed to MyPlate. To build a healthy plate of food, choose enough fruits and vegetables to cover one half of your plate. Then make your grains and protein fill the other half. And be sure to drink a lot of milk to keep your bones and teeth strong and healthy. MyPlate makes it easy to get the nutrition that you need and with very little effort.

U.S. Department of Agriculture

So how much is a serving?

You may be eating good foods each day, but still are not as healthy as you could be because of the amount of food you eat. How much food you eat can be as important to your good health as what you eat.

Many of the portions that we eat today are much larger than the recommended "serving" size. Look at what is considered to be a serving size: in general, 1 slice of bread, 1 cup of ready-to-eat cereal, or 1/2 cup of cooked rice, cooked pasta, or cooked cereal can be considered a 1 ounce equivalent from the grains group. Ideally, 1/2 of those grains should be whole grains.

Check out these charts from to see how much you should eat:

U.S. Department of Agriculture

What is a healthy diet?

A healthy diet provides all the nutrients we need in a day. The amount a child needs from each food group depends on age, gender and daily physical activity. Children who are very physically active, for example, need more than children who get little or no physical activity.

fruit bowl

Why is water so important?

water bottles

Water is the most necessary nutrient of them all. People can't survive for more than a few days without it. Your body is approximately 70% water. You lose precious water each day in your normal activities of breathing, sweating and other things. Your blood is mostly water, which is how it moves nutrients and oxygen to all of your cells. In addition, water helps to lubricate your joints, helps you fight infection and helps your memory — just to name a few. So drink up, drink lots, and drink often. Learn more about keeping healthy with water here.

Quick Tips to Healthy Eating:

balanced meal
  • Make half your grains whole grains
  • Fill half of your plate with vegies and fruit
  • Eat lean proteins
  • Find a good balance between eating and exercise
  • Eat calcuim-rich foods

What About Milk?

pitcher of milk

Students need the calcium and other essential nutrients in milk to help their bones grow in length and density, and for healthy teeth. You should get about 3 servings a day of milk, yogurt and cheese. Dairy is a great source of calcium, potassium and protein. Check out these other facts on dairy.

What is a Calorie?

A calorie is a unit of measure, just like an inch or pound. Calories measure how much energy food gives your body. Calories also measure how much energy you use up when you are active. When you eat, your body uses food as fuel, burning it to produce energy. Your body needs energy to function.

Calories in some foods are easier for your body to use. Experts recommend you get about half of your calories from carbohydrates, about 1/5 of your calories from proteins, and fats should provide no more than 1/3 of your calories.

Food and your weight

Your weight stays the same when the number of calories you take in from food equals the number of calories your body uses to maintain itself and be active. That is, if the calories you consume in a day meet your body's demands, all the calories will be converted to energy. If the number of calories are more than what your body uses and needs, the calories are stored as fat. If you eat too few calories your body may not have enough energy to fuel its cells. Then you won't have much energy and you may not be able to think clearly.

So in order to maintain a well-balanced diet, you should drink plenty of water, eat healthy portions of foods from all the food groups and have plenty of physical activity.

Why Is Physical Activity Important?

Healthy children are both well-nourished and physically fit. Physical activity means movement of the body that uses energy. Walking, bike riding, playing tag, climbing the stairs, playing soccer, or dancing are all good examples of being active. For health benefits, physical activity should be moderate or vigorous and add up to at least 30 minutes a day. Discover more about why exercise is cool.

Exactly how does your body use food?

human intestine

Your digestive system is the series of organs and glands that processes food in order to get all the nutrients from the food you eat.

It starts breaking down food even before you take your first bite and continues to work long after you've stopped eating.

Your small intestine is about 22 feet long!!

You are now an expert about nutrition and a healthy diet. Challenge yourself to eat healthy and get plenty of physical activity every day!!

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