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Nutrients Affecting Calcium
Balance
Several nutrients significantly
influence calcium balance:
* Vitamin D has a positive impact on
calcium balance, as it increases
calcium absorption in the
gastrointestinal tract. The most
readily available source of vitamin
D is exposure to direct sunlight.
Vitamin D is also found in fatty
fish, eggs, liver, butter, fortified
foods such as milk and
multivitamins. Vitamin D deficiency
may be a problem among some elderly,
those in institutional settings, and
some people with chronic
neurological or gastrointestinal
diseases.
* Protein is essential in our diets
to build tissue during growth and to
repair and replace tissue throughout
the life cycle. It is also needed
for fracture healing and proper
function of the immune system.
Protein deficiency is an important
factor contributing to death,
institutionalization, and loss of
independence among the elderly
following hip fracture.
However, protein also increases the
body's need for calcium by
increasing calcium excretion. Excess
protein in the diet is used by the
body for energy, just like fats and
carbohydrates. However, as protein
is burned for energy, it produces a
chemical called sulfate, which the
body excretes through the kidneys.
Sulfate increases the excretion of
calcium.
It is generally believed that most
Americans exceed the recommended
intake for protein--44 grams for
women and 56 grams for men.
* Sodium (and chloride), the
components of table salt, increase
the calcium requirement by
increasing urinary calcium
excretion. Individuals with low salt
intakes may be able to maintain
calcium balance at low calcium
intakes, while those with more
typical U.S. salt intakes will have
higher calcium requirements.
* Oxalate is a nutrient that
increases the calcium requirement by
interfering with calcium absorption
in the same food (not in others).
Spinach, for example, is an
extremely nutritious food, but its
calcium is not absorbed because it
is chemically bound to the oxalates
that are present. However, eating
spinach with cheese would not affect
the absorption of calcium from the
cheese. Foods high in oxalates
include spinach, rhubarb and sweet
potatoes.
* Phosphorous. Some concern has been
expressed that there may be too much
phosphorous in the North American
diet, particularly since phosphorous
(in the form of phosphoric acid) is
a constituent of cola beverages and
because phosphate is added to many
processed foods. Phosphorous may
increase the body's need for calcium
by interfering with calcium
absorption. There is no scientific
consensus that current levels of
phosphorous intake are, by
themselves, harmful. There is,
however, general agreement that
today's higher phosphorous intakes
would be entirely safe in
individuals with normal kidney
function if calcium intakes were at
recommended levels.
* Caffeine. The amount of caffeine
in a cup of coffee can reduce
calcium absorption by a few
milligrams, but that loss can be
easily offset by adding a tablespoon
or two of milk. Much of the
apparently harmful effect of
caffeine appears to be due not to
the caffeine itself, but to the fact
that caffeine-containing beverages
are often substituted for milk in
the diet.
* Fiber. Adequate fiberintake is
necessary to aid digestion and
prevent several chronic diseases
such as colon cancer and heart
disease. Fiber has a minimal effect
on the absorption of calcium. The
fiber in wheat bran is most likely
to interfere, but unless the intake
level is extreme, this is not a
significant problem.
Content Courtesy : www.osteo.org
Note : Information herein is
provided for informational purposes
only and is not a substitute for
professional medical advice. You
should not use this information for
diagnosing or treating a medical or
health condition. If you have or
suspect you have a medical problem,
promptly contact your professional
healthcare provider. Please consult
your healthcare provider before
beginning any course of
supplementation or treatment.
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