Download NUTRIENTS: You Just Can`t Live Without `Em

NUTRIENTS:
You Just Can’t Live Without ‘Em
“Do you want fries with that cheeseburger?”
“Sure, and a large soda, please.”
You’ve ordered a great-tasting lunch, but is it a healthy meal? The good news is
that you’re getting many of the nutrients you need. The bad news is that you’re
also about to eat a lot of stuff that you don’t need – like extra salt and fat.
When you choose what to eat, you need to think about more than your taste buds.
You need to know what your body needs and what foods will give it to you. You
need to know about nutrients.
What are nutrients? Nutrients…
1. fuel your body giving you the energy you need,
2. are used for growth and repair,
3. and help you fight disease.
There are six types of nutrients:
1. carbohydrates (sugars and starches)
2. proteins
3. fats
4. vitamins
5. minerals
6. water
Carbohydrates: Energy to Burn
The two most important kinds of carbohydrates are sugars and starches. The
simplest form of carbohydrate is the sugar glucose. Glucose is your body’s
favorite fuel.
Starches are another kind of carbohydrate that your body uses as fuel. Starches
include pasta, bread and rice. To use starches as a fuel, your body first has to
break them apart into sugars.
Carbohydrates that are not used as fuel aren’t wasted. Some of it is stored as
glycogen in our muscles and liver. If you eat more food than is needed, some of it
is turned into fat. Fat is how your body stores fuel for the future.
If you continually eat too much starch or sugar (corn syrup, candy, soft drinks,
etc.), you can quickly store too much fat and gain weight. Also, candy bars and
soft drinks usually don’t contain other nutrients like minerals and vitamins that you
can get from fruits and vegetables.
Fiber is another carbohydrate. Fibers can’t be digested by your body, but they are
still important. Fiber helps move food through your intestines.
Proteins: The Body Builders
You need proteins to:
 build tissue (growing)
 repair damage (cuts, sore muscles)
 make hemoglobin, which carries oxygen through your blood.
When you digest food, your body breaks
protein down into amino acids. There are 20
different kinds of amino acids that our bodies
use to build tissue, repair damage and make
hemoglobin.
Your body can make 11 of the amino acids by
combining carbon, hydrogen, oxygen and
nitrogen. The other nine amino acids cannot
be made by your body. These nine amino
acids are called the essential amino acids.
They are essential (or you must have them) because you must get them from the
foods you eat.
Foods that contain all nine essential amino acids are called complete proteins.
Foods that come from animals (meat, eggs, milk) have complete proteins.
Incomplete proteins do not have all nine essential amino acids. Foods that come
from plants (vegetables, fruits, wheat, rice) contain incomplete proteins.
How do vegetarians get by? If you don’t want to eat meat or animal products, you
can still get your essential amino acids. Just make sure that you combine foods
that, together, have all nine essential amino acids. For example: a meal that
combines black beans and rice, or lentil soup and corn bread, will give you the
complete proteins that you need.
Fats: What’s the Skinny?
Too much fat can cause health problems such as obesity (being overweight from
the accumulation of body fat) and heart disease. But fat isn’t all bad news.
The good news…
 Fat has more energy than proteins or carbohydrates. A gram of fat has about
twice as much energy as a gram of protein or carbohydrates.
 Thin layers of fat act as padding around your heart and other organs.
 Fat helps insulate your body to keep you warm.
There are two kinds of fats.
saturated: most fats from animals, including butter and eggs, are saturated fats.
They can turn into cholesterol – a substance that may collect inside your blood
vessels and block them. Blocked blood vessels can cause heart attacks.
non-saturated: most fats that come from plants are unsaturated fats. These
include nuts, fish and vegetables.
Although you need fats, you only need a small amount. The fatty foods that you
eat should contain mostly unsaturated fats.
Which of these foods contain saturated fats?
Which contain unsaturated?
Vitamins: The ABC’s of Health
Vitamins are chemicals that have been made by a living thing. Scientists have
discovered 13 vitamins, and each of these vitamins help your body function. Some
vitamins help your body build blood cells and some help control your nervous
system. Vitamins do other things as well.
You only need a tiny amount of vitamins, but your body can’t make them. The
best sources of vitamins are fresh fruits and vegetables.
Minerals: Little Things That Mean a Lot
Minerals are chemicals that are found in the environment. Minerals come from the
earth. Plants absorb them into their roots as they grow. These minerals are passed
on to animals when they eat plants. They are not made by living organisms.
Minerals are used to:
 build bones, teeth, and blood cells
 control the signals your body uses to control how its works
You can get minerals from many foods,
including fruits, vegetables and grains. You
can also get minerals from meat and milk.
Calcium is an important mineral you can get
from milk and cheese. Your body uses
calcium to build hard, strong bones and teeth.
Iron is also an important mineral that your
body uses. You need iron to make
hemoglobin, which helps you carry oxygen
throughout your body. Beef, tuna and chicken
are good sources of iron.
Water: Where it All Comes Together
Your brain and muscles are three-fourths water, and bone is 20 percent water.
Every cell in your body is packed with water.
Your body needs water to:
 transport nutrients and wastes
 control your body temperature
 carry out chemical reactions
Everyday, your body loses more than two liters of water. You can replace some of
it with food, but you should also drink six to eight glasses of liquid a day.
So What’s For Dinner?
The best way to get the nutrients you need is to eat good, fresh food. Knowing
about nutrients will help you choose the foods that your body needs.
NAME:
NUTRIENTS: You Can’t Live Without ‘Em
1. What does your body do with glucose that it does not use?
2. Name three ways our bodies use protein?
3. Explain how fat can be helpful and harmful to your body. Be sure to
include examples to support your answer.
4. Junk food, like candy and soda, contain all the carbohydrates your body
needs for energy. If so, why would a diet of only junk food be harmful to
your health?
5. Some schools are debating whether or not vending machines should be allowed
in their building. Do you think vending machines should be allowed at Moreau
Elementary School? If so, what types of beverages or snacks should be sold?
Write a scientifically reasoned essay that gives your opinion on this issue. Assume
that schools should provide students with a healthy environment. You must
include facts you learned from this article to justify your opinion.