Blood Enrichment LESSON 3 Iron Overload

Name
Date
Enrichment
Class
LESSON 3
Blood
Iron Overload
Iron is in foods such as spinach, poultry,
red meat, and cereals. It helps keep people
healthy. Iron is an important part of
hemoglobin, the pigment that gives blood
its color. Oxygen binds to the iron in
hemoglobin and travels with it to every
tissue in the body.
If your hemoglobin does not have
enough iron, your tissues will not receive
enough oxygen. You will feel tired, and your
head will ache. Your heart will beat faster,
striving to send more oxygen to your cells.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Poison in the Blood
Not all people can tolerate iron,
however. For a small group of people,
iron works like a poison in the body.
These people have a disease called
hereditary hemochromatosis (HH). Their
bodies absorb too much iron from food,
and they suffer from iron overload. On
average, adults absorb about 10 to 15
percent of the iron they consume. People
with HH absorb about 30 percent of the
iron in foods and about 50 percent of the
iron in vitamins.
HH affects about 1 million Americans.
It is caused by a genetic defect. There is
currently no cure for HH. However, the
disease is fairly easy to detect and treat.
Early treatment can prevent serious illness.
Unfortunately, about 95 percent of HH cases
are undiagnosed. Early symptoms of the
disease—fatigue, weakness, sore joints—are
often mistaken for more common ailments.
Symptoms usually don’t appear until
someone is between 40 and 60 years old.
If left untreated, HH can lead to serious
illnesses such as liver cancer, heart disease,
diabetes, and arthritis. Only during
treatment of these other diseases do doctors
discover the underlying cause—decades of
iron buildup from HH.
Blood Tests
Luckily, medical experts are taking
action to ensure that HH is detected early.
They recommend adding a test for iron
levels to blood tests. One medical testing
laboratory now tests all blood for iron
levels. The Centers for Disease Control and
Prevention in Atlanta is working to make
early testing for HH a standard practice.
Applying Critical-Thinking Skills
Directions: Respond to each statement.
1. Compare Use statistics about HH to compare how iron is absorbed from foods and
from vitamins.
2. Evaluate Based on what you know about HH, choose whether you think your diet
should include iron-rich foods or whether you should avoid these foods. Justify your
answer.
Respiration and Circulation
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