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What does it do for
your body?
BONES AND TEETH - The main function of
calcium is the development and maintenance of healthy bones and teeth. Bone is made up of cells and fiber
embedded in a mineral matrix, which is mostly crystals of
calcium phosphate. One form of bone calcium is bound
tightly within the bone and the other is easily removed
to maintain blood levels. Calcium is removed from the
tightly bound part of the bone only when the more mobile
stores are exhausted and dietary intake is inadequate.
Bones are constantly being replaced with 20% of an
adult’s bone calcium reabsorbed and replaced every
year.
NERVE AND MUSCLE CONTRACTION - Calcium is essential for
muscle contraction, including that of the heart muscle
and for nerve impulse conduction. Increasing calcium may
normalise heart rhythm in arrhythmia sufferers. Calcium
also aids in the release of neurotransmitters which carry
messages between nerve cells.
BLOOD PRESSURE - Calcium interacts with sodium, potassium
and magnesium to regulate blood pressure. It has been
found that people whose diets are low in calcium are more
likely to suffer from high blood pressure. The effects of
a mother’s high calcium diet during pregnancy may
also be passed on to her children who will be less likely
to suffer from high blood pressure. major class of drugs
used to lower high blood pressure blocks the channels
which transport calcium across muscle cell membranes.
There is currently an ongoing debate as to whether these
calcium channel blockers increase the risk of heart
attacks.
BLOOD - Calcium in the blood is essential for clotting by
activating vitamin K (prothrombin) which is the first
stage in wound healing.
It is also involved in the control of blood cholesterol
levels. Increased calcium may lower blood cholesterol
levels and reduce the risk of developing premature heart
disease.
IMMUNE FUNCTION - Calcium in milk has been shown to
enhance resistance to salmonella in rats.
METABOLISM - Calcium is essential for the production and
activity of many enzymes and hormones that are involved
in digestion, energy and fat metabolism and the
production of saliva. Diabetics often have increased
levels of calcium in their cells and the resulting
disturbance in metabolism may play a role in some of the
complications of diabetes such as heart disease and
cataracts.
CELL MEMBRANES - Calcium is involved in the transport of
nutrients and other substances across cell membranes and
aids in the maintenance of connective tissue which holds
cells together.
Lactation increases the ability of women to absorb
calcium after weaning or the resumption of menstrual periods. Deficiency and moderate exercise also increase
absorption and the efficiency of absorption decreases as
intake increases.
Dietary calcium must be made soluble in the stomach and
then pass to the small intestine where it combines with a
calcium binding molecule so it can be absorbed (chelation). Calcium competes with zinc, manganese,
magnesium, copper and iron for absorption in the
intestine and a high intake of one can reduce absorption
of the others. However, these other minerals in the right amount are
beneficial for calcium absorption.
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