BASIC NUTRITION GUIDELINES
Protein: On the Scene!
Some types of amino acids are made by you, right inside your body, without you ever thinking about it or doing anything special. These are called nonessential amino acids, and there are 11 of them. And they are necessary - meaning you need them to keep your body in tip-top shape - but they are not essential as part of the food you eat. The essential amino acids - all nine of them - must come from food. No matter how hard you concentrate or how still you sit, your body won't ever make essential amino acids. That's where eating foods with protein comes in, to give your body the amino acids it needs.
Why Do We Need Protein?
Protein is so important that your body needed it and used it even before you
were born. Your body uses protein in lots of ways. Protein's
biggest job is to build up, keep up, and replace the tissues in your
body. Your muscles, your organs, even some of your hormones are made up
mostly of protein.
Protein helps your body in other ways, too. It likes to make sure things get around by making hemoglobin, the part of red blood cells that carries oxygen to every part of your body. It even makes antibodies, the cells that fight off infection and disease. It's what helps make your cuts and scrapes heal.
It's easy to get the protein your body needs. Protein is in tasty foods like meat, chicken, fish, eggs, and nuts. Dairy products like cheese, milk, and yogurt are good sources of protein. Lentil beans or peas are also full of protein.
The Great Carbohydrate
Starchy carbohydrates have their own name, too: complex carbohydrates. These carbohydrates take longer to be digested than simple carbohydrates do. Complex carbs are found in foods like bread, noodles, and rice, and in lots of tasty veggies.
Why Do We Need Carbohydrates?
Carbohydrates have an important job: giving all the cells in your body the
energy they need. When you eat foods with carbohydrates in them, your body
breaks them down into two different types of fuel.
For energy that you'll use right away, your body takes those carbs and turns them into glucose, which is carried in your blood to all the cells in your body, and gives you energy. It powers every part of your body. Glucose lets you run, jump, think, blink, breathe, and more. Whatever you do, as long as you're using your body, you need the great power of glucose. Have you ever felt hungry and found it kind of hard to think? That's because you were running out of glucose, and your brain needed more fuel.
But your cells can only use so much glucose at one time. So when there is glucose left over that can't be used right away, your cells save it. But there's no sticking it in the refrigerator like regular leftovers - instead, this leftover glucose is stored in your liver and muscles, and it's called glycogen. The glycogen that doesn't fit into your liver and muscle cells is turned to fat.
Glycogen hangs out until it's needed, and is then released for quick energy when you're exercising. Your body decides to release the power from either glycogen or fat depending on the type of sport or activity you're doing, and how long you're doing it. If you're sprinting or doing another quick exercise, your body calls on glycogen for energy. But if you are exercising for a long time, your body turns to its "reserve tank" of fuel for energy: fat.
How Do We Get Carbohydrates?
Carbohydrates are in lots of foods, but carbs are very different from each other
- and if you guessed that complex carbs are different from simple carbs, you're
right! That's because simple carbohydrates
are absorbed into your blood much faster, and while they provide some really
quick energy, they can often come with lots of fat and lack important vitamins
that your body needs. So while a can of soda or a candy bar every once in
a while isn't too bad, you wouldn't want to make these simple carbohydrates a
regular part of the food you eat.
Many fruits are a good source of simple carbs, though - so if you're looking for some quick energy and a healthy snack, these are the way to go: apples, bananas, grapes, and raisins pull out in front of the simple carbs pack. And fruit cocktail, oranges, and pears will get carbs in there. Ice cream and frozen yogurt are good ways to get simple carbs, as well as fat, protein, and other vitamins and minerals.
Complex Carbohydrates
Complex carbohydrates are the slowpokes of the
group: they give you energy more slowly. They take longer to be digested, so
your body needs more time to release these carbs into your blood as glucose.
Complex carbs are better when you are exercising or playing in a game, because
you can count on them to give you energy that lasts through the ninth inning or
the fourth quarter! Complex carbs also beat simple carbs because they usually
come with lots of vitamins and minerals your body needs.
It's easy to get the complex carbs your body likes to use as fuel - they are in bread, cereals, pasta, rice, oatmeal, pretzels, and even bagels. If you're a veggie fan, then you're in luck, because corn, potatoes, sweet potatoes, tomatoes, carrots, cucumbers, lettuce, and peppers are all great ways to get complex carbs.
All That Fat
Fat sometimes sounds like it's always a bad thing that people should not eat,
but actually our bodies need some fat to work correctly. Fat insulates our
bodies from the cold and provides some cushioning for our organs. Fat gives our
bodies energy. Some fats help to make up important hormones that we need to keep
our bodies at the right temperature or keep our blood pressure at the right
level. Fat helps you have healthy skin and hair. And fat is like your body's
very own storage and moving service: it helps vitamins A, D, E, and K hang out and
get transported through your bloodstream when your body needs them!
How Do We Get Fat?
Even though our bodies need some fat to work properly, they
don't need as much as most people eat. It's a good idea to avoid eating a lot of
fat, because it can contribute to obesity (when a person weighs much too much
for his or her height) and other illnesses that can occur when you're older,
like heart disease or adult-onset diabetes.
But foods with lots of fat in them taste good - like cookies, chocolate, and fast-food hamburgers and french fries! It's OK to eat cake and ice cream once in a while, but the real trick is not to eat these kinds of foods all the time, or even most of the time. Instead, you should eat them in small doses, and infrequently. Staying healthy and keeping your body in shape is easier when you go for foods and snacks that are lower in fat - and you'll feel better, too!
CALORIES
A calorie is a measure of how much energy the nutrients protein, carbohydrate, and fat can supply your body. When you eat food, your body uses the food as fuel, burning it to produce energy, or calories. Every person's body needs energy to function. Whether your body is doing things you don't even think about, like pumping blood or blinking, or doing things you plan, like walking a dog or blowing your nose, you always need calories!
Some types of nutrients have more calories than others. When you eat foods with protein, every gram of protein gives you four calories (a gram weighs about the same as the amount of sugar that's in a packet at a restaurant). Same deal with carbohydrates: when you eat foods with carbohydrates, your body burns the food as fuel and gives you four calories for every gram of carbohydrate. And fat gets its reputation for being fattening because when your body burns it, you end up with nine calories for every gram of fat! That's more than twice the amount!
1 cup of milk has 8 grams of protein, so:
8 grams X 4 calories = 32 calories from protein
1/2 cup of cooked spaghetti has 17 grams of carbohydrate, so:
17 grams X 4 calories = 68 calories from carbohydrate
1 order of "large fries" from your favorite fast-food restaurant has 22 grams of fat, so:
22 grams X 9 calories = 198 calories from fat
So if it's energy your body is after, you might think that the large fries would be best, since they give you so many calories, right? The answer is. . .nope! That's because your body can only use so many calories at one time. Whatever calories your body doesn't burn for fuel, it stores in your body as fat. So even though they taste good, foods that get a lot of their calories from fat aren't quite as great as they seem. . .in fact, if you eat a lot of them, you can end up gaining weight.
The key to keeping your body healthy is to remember that your body uses food for energy. When you are active, your body burns lots of calories to let run far or run fast. But when you are watching TV or a movie, your body doesn't burn nearly as many calories - you just don't need that much energy to laugh at your favorite show!
So the trick to keeping your body at a weight that's good for your height is to eat as many calories as you burn off. If you eat more calories and exercise less, the energy has nowhere to go, and you gain weight. The more you exercise, the more calories you can have, because there is a good balance between the two. But don't forget, it's still a good idea to get most of your calories from protein and carbohydrates. Fat won't hurt you if you eat it in moderation (moderation means eating it a little bit, and not very often), and it tastes good, but fat should make up a little less than 1/4 of all the calories you eat.
READING FOOD LABELS
You know how books have a table of contents that explains what's inside? Or maybe you've received a gift that came with a diagram that identified each small piece. Nutrition labels are sort of like that. They tell you what's inside the food you're eating and list its smaller parts.
The Nutrition Facts food label gives you information about which nutrients are in the food. Your body needs the right combination of nutrients, such as vitamins, to work properly and grow. The Nutrition Facts food label is printed somewhere on the outside of packaged food, and you usually don't have to look hard to find it. Fresh food that doesn't come prepackaged sometimes has nutrition facts, too.
Most nutrients are measured in grams, also written as g. Some nutrients are measured in milligrams, or mg. There are one thousand milligrams in a gram. Other information on the label is given in percentages. These numbers are based on eating 2,000 calories in a day, the amount that many school-age kids eat . A calorie is a unit of energy, a way of expressing how much energy you would get by eating a certain food.
If you want to learn more about the different types of information on food labels, keep reading. We'll start at the top of the label and work our way down.
Serving Size
The nutrition label always lists a serving size, which is an amount of food,
such as 1 cup of cereal, two cookies, or five pretzels. The nutrition label
tells you how many nutrients are in that amount of food. Serving sizes also help
people understand how much they're eating. If you ate 10 pretzels, that would be
two servings.
Servings per Container or Package
The label also tells you how many servings are contained in that package of
food. If there are 15 servings in a box of cookies and each serving is 2
cookies, then you have enough for all 30 kids in your class to have one cookie
each. Math comes in handy with food labels.
Calories and Calories From Fat
The number of calories in a single serving of the food is listed on the left of
the label. This number tells you the amount of energy in the food. People pay
attention to calories because if you eat more calories than your body uses, you
might gain weight.
Another important part of the label is the number of calories that come from fat. People check this because it's good to limit fat intake. The calories in a food can come from fat, protein, or carbohydrate.
Percent Daily Value
You'll see percentages on food labels that are based on recommended daily
allowances - meaning the amount of something a person should get each day. For
instance, there's a recommended daily allowance for fat, so the food label might
say that one serving of this food meets 10% of the daily value. The daily values
are based on an adult's needs, not a kids' needs. These are often
similar, but kids need may need more or less of certain nutrients, depending on
their age and size.
Some percent daily values are based on the amount of calories and energy a person needs. These include carbohydrates, proteins, and fat. Other percent daily values - like those for sodium, potassium, vitamins, and minerals - stay the same no matter how many calories a person eats.
Total Fat
The total fat is the number of fat grams contained in one serving of the food.
Fat is an important nutrient that your body uses for growth and development, but
you don't want to eat too much. The different kinds of fat, such as saturated,
unsaturated, and trans fat, may be listed separately on the label.
Cholesterol and Sodium
These numbers tell you how much cholesterol and sodium (salt) are in a single
serving of the food. They are included on the label because some people need to
limit cholesterol or salt in their diets. Cholesterol and sodium are usually
measured in milligrams.
Total Carbohydrate
This number tells you how many carbohydrate grams are in one serving of food.
Carbohydrates are your body's primary source of energy. This total is broken
down into grams of sugar and grams of dietary fiber.
Protein
This number tells you how much protein you get from a single serving of the
food. Your body needs protein to build and repair essential parts of the body,
such as muscles, blood, and organs. Protein is often measured in grams.
Vitamin A and Vitamin C
These list the amounts of vitamin A and vitamin C, two especially important
vitamins, in a serving of the food. Each amount is given as a percent daily
value. If a food provides 20% of the RDA for vitamin A, that one serving of food
gives an adult one fifth of the vitamin A needed for the day.
Calcium and Iron
These list the percentages of calcium and iron, two especially important
minerals, that are in a serving of the food. Again, each amount is given as a
percent daily value. If a food has 4% of iron, you're getting 4% of the iron you
need for the whole day from that serving.
Calories per Gram
These numbers show how many calories are in one gram of fat, carbohydrate, and
protein. This information is the same for every food and is printed on the food
label for reference.
Now that you know a little more about food labels, you can read up on what you're eating!
Updated and reviewed by: Jessica
R. Donze, RD, CDE
Date reviewed: July 2003
Originally reviewed by: Heidi
Kecskemethy, RD, CSP