What Is Anemia?
Maybe your day is so packed with things to do that you hardly
have time to grab breakfast, let alone make sure you're eating
right the rest of the day. Perhaps you're staying up late to
get your homework finished and missing out on the sleep you need.
The fact is, lots of teens are tired. And with all the demands of
school and other activities, it's easy to understand why.
For some people, though, there may be another explanation for
why they feel so exhausted: anemia.
To understand anemia, it helps to start with breathing. The
oxygen we inhale doesn't just stop in our lungs. It's
needed throughout our bodies to fuel the brain and all our other
organs and tissues that allow us to function. Oxygen travels to
these organs through the bloodstream - specifically in the red
Red blood cells, or RBCs, are manufactured in the body's
and act like boats, ferrying oxygen throughout the rivers of
the bloodstream. RBCs contain
muh-glow-bin), a protein that holds onto oxygen. To make enough
hemoglobin, the body needs to have plenty of iron. We get this
iron, along with the other nutrients necessary to make red blood
cells, from food.
Anemia occurs when a person has fewer RBCs than normal. This can
happen for three main reasons:
- Red blood cells are being lost.
- The body is producing RBCs slower than it should.
- RBCs are being destroyed by the body.
Each of these causes is linked to a different type of
When a small amount of blood is lost, the bone marrow is able to
replace it without a person becoming anemic. But if a large amount
of blood is lost over a short period of time, which can happen if
someone has a serious accident or injury, for example, the bone
marrow may not be able to replace the red blood cells quickly
Losing a little blood over a long period of time also might lead
to anemia. This can happen in girls who have heavy menstrual
periods, especially if they don't get enough iron in their
Iron Deficiency Anemia
Iron deficiency anemia is the most common type of anemia in U.S.
teens. It occurs when a person's diet is lacking in iron. Iron
deficiency - when the body's stores of iron are reduced - is
the first step toward anemia. If the body's iron stores
aren't replenished at this point, continuing iron deficiency
can cause the body's normal hemoglobin production to slow down.
When hemoglobin levels and red blood cell production drop below
normal, a person is said to have anemia. Someone with anemia may
appear pale and may be tired all the time.
There are other nutritional reasons why someone's body may
not make enough RBCs. Vitamin B12 and folic acid are also needed to
make red blood cells, so it's important to get enough of these
nutrients in your diet. If the bone marrow is not working properly
because of an infection, chronic illness, or certain
medications like chemotherapy, anemia can develop.
In a person with hemolytic (pronounced: hee-muh-
-tik) anemia, the normal lifespan of the red blood cells is shorter
than normal. When blood cells die off early, the bone marrow is
unable to keep up with production. This can happen for a variety of
reasons. A person may have a disorder like
sickle cell anemia
. In other cases, the body's own immune system can cause
destruction of RBCs. Antibodies can be formed as a reaction to
certain infections or drugs that attack the RBCs by mistake.
Why Do Teens Get Anemia?
Because teens go through rapid growth spurts, they can be at
risk for iron deficiency anemia. During a growth spurt, the body
has a greater need for all types of nutrients, including iron,
which we need to get in the foods we eat.
After puberty, girls are at more risk of iron deficiency anemia
than guys are. That's because a girl needs more iron to
compensate for the blood lost during her menstrual periods.
Pregnancy can also cause a girl to develop anemia. And a teen on a
diet to lose weight may be getting even less iron.
Vegetarians are more at risk of iron deficiency anemia than
people who eat meat are. Red meat is the richest and best-absorbed
source of iron. Although there is some iron in grains, vegetables,
and some fruits and beans, there's less of it. And the iron in
these food sources is not absorbed by the body as readily as the
iron in meat.
What Are the Symptoms?
It's easy for people to overlook the symptoms of anemia
because it often happens gradually over time. Looking pale can be a
sign of anemia because fewer red blood cells are flowing through
the blood vessels. The heart will beat faster in an effort to pump
the same amount of blood and oxygen to the body, so the pulse may
be faster than normal.
As anemia progresses, a person may feel tired and short of
breath, especially when climbing stairs or working out. They may
develop headaches. Iron deficiency, which occurs before iron
deficiency anemia develops, may affect a person's ability to
concentrate, learn, and remember.
Anemia is not contagious, so you cannot catch it from someone
who has it.
How Is Anemia Diagnosed?
If you visit a doctor for suspected anemia, he or she will
probably give you a
. The doctor will also ask questions about any concerns and
symptoms you have, your past health, your family's health (such
as whether anyone in your family has anemia), any medications
you're taking, any allergies you may have, and other issues.
This is called the
As part of this medical history, your doctor may ask specific
questions about the foods you eat. If you're a girl, the doctor
may ask questions about your periods, such as how heavy the flow
is, when you got your first period, how often you menstruate, and
for how many days.
If your doctor suspects you are anemic, he or she will probably
take a blood sample and send it to a lab for analysis. This will
determine, among other things, the number, size, and shape of your
red blood cells, the percentage of your blood that is made up of
RBCs, and the amount of hemoglobin present in the blood. With this
information, a doctor can determine if a person is anemic and may
order additional tests (like measuring iron levels), depending on
the suspected cause of the anemia.
How Is Anemia Treated?
The treatment of anemia depends on what's causing it. If the
anemia is caused by iron deficiency, your doctor will probably
prescribe an iron supplement to be taken several times a day. Your
doctor may do a blood test after you have been on the iron
supplement. Even if the tests show that the anemia has improved,
you may have to continue taking iron for several months to
replenish your body's total iron stores.
Because some people become nauseated if they take an iron
supplement on an empty stomach, it can help to take it with food.
Vitamin C boosts iron absorption, so drink a glass of orange or
grapefruit juice when you take your iron. You can increase the
chances that the iron you get from food will be absorbed by your
body in other ways, too. For example, avoid drinking tea with food
because a substance in tea called tannin reduces the body's
ability to absorb iron found in the food or iron supplement.
Milk can also interfere with iron absorption, so don't pair
milk with iron-rich foods if you are concerned about getting enough
Some people need more iron than others: Girls need more than
guys, for example. And a girl who has heavy periods has a greater
need for iron than a girl who has a light flow.
To make sure you get enough iron, eat a balanced diet every day,
starting with a breakfast that includes an iron source, such as an
iron-fortified cereal or bread. Lean meat, raisins, spinach, eggs,
dried beans, and molasses are also good sources of iron.
If someone's anemia is caused by another medical condition,
doctors will work to treat the cause. People with some types of
anemia will need to see a specialist, called a
hematologist, who can provide the right medical care for their
The good news is that for most people anemia is easily treated.
And in a few weeks you'll have your energy back!
James Fahner, MD
Date reviewed: June 2007
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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