76 Unit 2 Nutrition and Food Choices
Copyright Goodheart-Willcox Co., Inc.
Water-soluble vitamins dissolve in water, pass into the bloodstream
during digestion, and are either used immediately by the body or are re-
moved by the kidneys during urination. For this reason, these vitamins
should be included in your meals every day. There are nine water-soluble
vitamins—vitamin C and the B vitamins.
Fat-soluble vitamins dissolve in the body’s fats and are stored in the
body for later use. Because fat-soluble vitamins are stored by the body for
longer periods, excessive intake may result in toxic levels. There are four
fat-soluble vitamins—vitamins A, D, E, and K.
Sources of Vitamins
Where should you get your vitamins? Can’t you just pop a multivita-
min pill? Eating a balanced diet that contains a variety of foods can easily
provide you with the appropriate amounts of all the vitamins you need.
Obtaining vitamins from your daily diet is preferable to taking vita-
min supplements for several reasons. First, vitamin supplements do not
contain all of the nutrients and other substances that your body needs and
which are contained in foods. Some of these substances contained in food,
but not in supplements, may even help your body better utilize the vita-
mins. Furthermore, some supplements provide larger-than-needed doses
of vitamins, which may cause unhealthy levels in the body. A lesser prob-
lem with large doses of vitamins is waste—the unneeded amounts do not
stay in the body and are simply excreted in the urine.
When deciding whether or not to take a vitamin supplement, you
should consult your healthcare provider. People at certain life stages—such
as pregnant women, infants, and older adults—and individuals who are
ill may benefi t from vitamin supplements. However, their healthcare pro-
viders should recommend the amount and type of supplements to take.
Minerals
Minerals are inorganic elements that come from the earth, and which
are found in soil and water. Minerals are absorbed by plants from the soil
and water. You then absorb minerals from the plants you eat, the water you
drink, or from animal food sources that have absorbed the minerals.
Your body needs a total of 20 different minerals (Figure 3.7). These minerals
are divided into two distinct types—macrominerals and trace minerals. Macro-
minerals are those minerals your body needs in quantities greater than 100 milli-
grams a day to maintain good health. Trace minerals are those minerals your body
needs in very small amounts—less than 100 milligrams daily—to stay healthy.
Although only small amounts are needed, trace minerals are very important.
Your body needs minerals to grow and develop normally. People who
fail to take in enough of a particular mineral experience serious health con-
sequences, such as
• osteoporosis, a condition in which bones become fragile and may
break easily, which can be caused by a lack of calcium during
childhood and adolescence;
water-soluble vitamin
a type of vitamin that
dissolves in water and
passes into the bloodstream
fat-soluble vitamin
a type of vitamin that
dissolves in the body’s fat,
where it is stored for later
use
mineral
inorganic elements found
in soil and water; ingested
by the body after being
absorbed into plants
osteoporosis
a dangerous condition in
which bones are fragile and
may break easily; can be
caused by a lack of calcium
during childhood and
adolescence