IRON. You see the word everywhere, and not just in
chemistry class. There’s Iron Gaming and Iron Man comic
books, plus the rugged Ironman and Ironwoman Triathlons.
The Iron Age and the Iron Curtain crop up in history; the Iron
Mask in literature. Iron, everywhere you spot it, stands for
strength and power. But does element #26 belong on a must-have list of mineral nutrients for everyone? Absolutely.
How much iron do we need?
“Pumping iron” builds muscle, but an
internal supply is also required. Without iron
in your diet, everything—from the energy
you need to get to school in the morning to
the brain power you need to concentrate on
this article—will fade away. Your body
contains 0.006–0.01% of iron by
weight—about 4 grams for a man
and 3. 5 grams for a woman, says
the Iron Disorders Institute. That is enough elemental
iron to make one medium-sized
It does not sound like much.
From iron’s reputation, you might guess
the hard, grayish metal used in tools
and weapons for more than 5,000 years
would be a primary chemical ingredient
of the human body. Not so. Iron is a
mere trace element in the body, less abundant
than phosphorus, sulfur, or chlorine. But that
tiny, vital amount is what keeps humans, ani-
mals, plants, and bacteria alive. It is essential
for metabolism and for normal cell function-
ing. Without it, living beings become “iron
Iron deficiency is a big deal. It is the most
common nutritional disorder in the world,
affecting as many as 2 billion people around
the globe. Iron is the only nutrient whose defi-
ciency is prevalent in industrialized coun-
tries, where, ironically, plenty of iron-rich
food is available.
Iron deficiency sneaks up on people,
causing no early symptoms. This lack of
iron takes its heaviest toll on the poor,
especially infants, children, and women—
in ways ranging from underdeveloped
brains to premature death. The problem
impacts everybody—especially fast-
growing teens, many of whom participate
in energy-burning sports, and menstruating
teenage girls, who need an extra dose of iron.
Iron is, by mass, the most common element on Earth. It is often combined with
oxygen, silicon, or sulfur, or alloyed with
carbon to make steel. Fe (from the Latin word
ferrum) atoms are found in soil and rocks. So
why can’t everybody get enough of it?
There are three main reasons for this. First,
iron is routinely lost through body fluids,
including blood, sweat, and tears. That is why
it needs regular replacement from food. The
usual daily requirement is 11
milligrams for teenage boys and
15 milligrams for teenage girls,
according to the U.S. National
Institutes of Health.
Second, people do not always eat enough
iron-rich foods—even though they may be on
the table—due to calorie-counting or a vegan
or vegetarian diet.
Third, your digestive system throws away
most of the iron you eat, absorbing only a
fraction. The body takes in enough—but not
too much—of this critical element by varying
the amount of iron absorbed based on the V I D E O
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