Calcium and its Role in Human Body

Abstract

Calcium is very essential in muscle contraction, oocyte activation, building strong bones and teeth, blood clotting, nerve impulse, transmission, regulating heart beat and fluid balance within cells. The requirements are greatest during the period of growth such as childhood, during pregnancy, when breast feeding. Long term of calcium deficiency can lead to oestoporosis in which the bone deteriorates and there is an increased rise of fractures. Eating a well-balanced diet can provide all the necessary nutrients and help prevent calcium deficiency. INTRODUCTION The group IIA of the periodic table contains the alkaline earth metals such as Ca, St, Ba and Ra. All the non metallic substances are insoluble in water and unchanged by five were called earths. Limes and magnesia showed alkaline reactions hence alkaline earths. The name calcium is derived from latin word calas meaning lime was known as early as the first centuries when the ancient Romans prepared lime as CaO. It was not actually isolated until 1808 in England when Sir Humphrey Davy electrolyzed a mixture of lime and mercuric oxide. Davy was trying to isolate calcium along with magnesium, strontium and barium.Out of alkaline earth group, Ca has achieved the greatest use and tonnage.

Full text

Vol. 4 (2) Apr– Jun 2013 www.ijrpbsonline.com 659
International Journal of Research in Pharmaceutical and Biomedical Sciences
ISSN: 2229-3701
______________________________________________Review Article
Calcium and its Role in Human Body
Piste Pravina*, Didwagh Sayaji and Mokashi Avinash
P.G .Department of Chemistry, Y. C. Institute of Science, Satara, Maharashtra, India.
ABSTRACT
Calcium is very essential in muscle contraction, oocyte activation, building strong bones and teeth, blood
clotting, nerve impulse, transmission, regulating heart beat and fluid balance within cells. The requirements
are greatest during the period of growth such as childhood, during pregnancy, when breast feeding. Long term
of calcium deficiency can lead to oestoporosis in which the bone deteriorates and there is an increased rise of
fractures. Eating a well-balanced diet can provide all the necessary nutrients and help prevent calcium
deficiency.
Key Words: Calcium, Oesteoporosis, Hypo and Hypercalcaemia, Parathyroid glands.
INTRODUCTION
The group IIA of the periodic table contains the
alkaline earth metals such as Ca, St, Ba and Ra. All
the non metallic substances are insoluble in water
and unchanged by five were called earths. Limes
and magnesia showed alkaline reactions hence
alkaline earths.
The name calcium is derived from latin word calas
meaning lime was known as early as the first
centuries when the ancient Romans prepared lime
as CaO. It was not actually isolated until 1808 in
England when Sir Humphrey Davy electrolyzed a
mixture of lime and mercuric oxide. Davy was
trying to isolate calcium along with magnesium,
strontium and barium.Out of alkaline earth group,
Ca has achieved the greatest use and tonnage.

Vol. 4 (2) Apr– Jun 2013 www.ijrpbsonline.com 660
International Journal of Research in Pharmaceutical and Biomedical Sciences
ISSN: 2229-3701
Calcium ranks fifth in the order of abundance of
elements in earth’s crust, the percentage being
estimated at 3.64. Calcium does not occur free in
nature being an active element.It occurs largely in
the form of carbomates and sulphates. As
carbonates, it occurs in the form of lime stone,
chalk, calcite, marble, Iceland spar, dolomite,
stalactite, stalagmite etc. and sulphate, it occurs in
the form of Gypsum and its anhydride form
calcium also occurs as a phosphate in the
phosphorite rock. CaSiO3 in many complex rocks,
fluoride in the form of fluorspar (Caf2).
Properties
The tensile property of calcium metal are greatly
affected by impurities and in the pure form by the
methods of fabrication. Calcium metal work upon
mechanical possessing. Bulk calcium is soft,
crystalline metal. It may be readily extruded on
heating to 420 – 4600C. X-ray diffraction pattern of
calcium samples exists in only two allotropic form
– face centered cubic and Body centered cubic
(4640C). According to Debye-Scherer, Ca exists in
three allotropic modifications i.e. α-Ca-face
centered cubic, β-Ca-hexagonal close packed and
γ-Ca-body centered cubic. It readily forms a white
coating of nitrite in air, reacts with water by
forming Ca(OH)2, burns with a yellow red flame
forming the largely the nitride. They are malleable,
extrudable and machinable may be in rods, wires or
plates. Calcium is cheapest of alkaline earth metals
but more expensive than Sodium. Ca metal itself
comates even in metallurgical work with some of
its own compounds e.g. calcium silicide, calcium
boride, calcium carbide, all of which are used as
degasifiers, reductants and sources of calcium for
alloys.
Isotopes
Calcium has four stable isotopes 40Ca, 42Ca, 46Ca
and 48Ca that have such long half lives that for all
practical purposes. They can be considered stable.
It has also cosmogenic isotope radioactive 41Ca
which has a half life of 1,03,000 yrs. 41Ca is
produced by neutron activation of 40Ca. It has
received much attention in stellar studies because it
decays to 41K, a critical indicator of solar system
anomalies. 97% of naturally occurring Ca is in the
form of 40Ca which is one of the daughter product
of 40K decay along with 40Ar. While K-Ar dating
has been used extensively in the geological
sciences.
Proportions
The body contains about 2% of Ca and 98% of this
is in the bones. The cell and body fluid contains
from 10 – 15 mg per 100 gm. The blood Ca is in
two distinct forms, a part is bound with protein and
is non diffusible while the diffusible moiety is
found as undissociated phosphates and carbonates
and as ionic calcium. The protein bound Ca does
not diffuse. Out of the blood, the cerebrospinal
fluid contains only 6 mg per 100 gm. The Ca in the
blood and tissues and that in the skeleton are in
equilibrium. The Ca of the bone can be drawn upon
to make up deficiency of blood Ca and when the
deficit is made up the Ca is redeposited in the bone.
The medication of parathyroid is necessary for the
withdrawal of Ca from the skeleton. In the body,
there is a balance in various forms of Ca. The ionic
forms of Ca is involved in the various
physiological activities.
Physiological role
Daily body requirement is about 450 mg. The adult
requirements of Ca vary. During pregnancy and
lactation, there is greater depletion of Ca from the
mother and the intake needs to be increased. On an
average, 10 mg per Kg of body weight per day
should be sufficient. Growing children would
require from 40 to 60 mg per day. A Cow’s milk
contains 0.126% of Ca. A litre of Cow’s milk
provides therefore a full day’s ration of Ca is
readily assimilable form. Generally sufficient Ca
gets ingested through the normal through the
normal diet. It gets from upper intestinal tract and
is excrete through urine and faeces. As the upper
portion of intestine the condition is acidic, it tends
to favour absorption of Ca. As Ca salts have better
solubility. The alkaline condition brings about the
precipitation of Ca salts and the absorption is
retarded. Higher fatty acid contents also decreases
the absorption due to formation of Ca salts of fatty
acid which are insoluble.
Calcium is essential to maintaining total body
health. Your body needs it every day not just to
keep your bones and teeth strong over your life
time but to ensure proper functioning of muscles
and nerves. It even helps your blood clot. Many
peoples think they are getting enough Ca every day
but the fact is, they are not so. Ca deficiency is
usually due to an inadequate intake of Ca when
blood Ca levels drop too low, the vital mineral is
borrowed from the bones. It is returned to the

Vol. 4 (2) Apr– Jun 2013 www.ijrpbsonline.com 661
International Journal of Research in Pharmaceutical and Biomedical Sciences
ISSN: 2229-3701
bones from Ca supplied through the diet. If an
individual’s diet is low in Ca, there may not be
sufficient amount of Ca available in the blood to be
returned to the bones to maintain strong bones and
total body health. Taking Ca regularly everyday is
key to preventing and treating Ca deficiency. So
how much daily Ca do you need? How much do
you get? It is very important to your health.
According to the U.K. Dept. of Health
recommended reference nutrients intake for Ca
required according to age. The infants and children
require 350 - 550 mg/day.
Teenage girls and boys : 800 – 1000
mg/day
Adult men and women : 700 mg/day
The Ca play an important role to maintain some
important body functions such as
i) Ca controls nerve excitability. The effect is
mainly on the peripheral neuromuscular
mechanism. Fibrillary twitching can be
produced by per fusing a muscle with Ca free
fluid. Automatic ganglia also become hyper
irritable.
ii) It is necessary for the maintenance of the
integrity of the skeletal muscles. An increase
in the ionized Ca results in an increase in
contractility and vice varsa.
iii) It is very essential for maintaining the tone
and contractility of heart. Ca is antidotal to
the depressant action of K.
iv) It aids rennin in the coagulation of milk in
the stomach.
v) It is essential for the clotting of food.It
decreases cellular permeability. It is
therefore used in allergic conditions to
diminish exudation which produces wheals
and rushes. Ca appears to serve as a
constituent of the intercellular cement.
vi) Ca take part in the formation of certain tissue
and bones. Normally 25 – 35% is excreted in
the urine and the rest in the stools.
A high protein diet especially derived from animal
foods causes Ca loss in the body. The higher
sulphur to calcium ratio of metal increases Ca
excretion and a diet righ in meal can cause bone
demineralization. A report published in 1988
comparing the amounts of Ca excreted in the urine
showed that, the animal – protein diet cause greater
loss of bone loss and hence Oestoporosis. It is the
major cause of bone fractures in the elderly. It is
better prevented than treated and prevention
includes an adequate intake of Ca throughout life
but especially in childhood and young adult hood
and minimizing risk factors e.g. smoking, heavy
alcohol use and lack of physical exercise. Diet high
in protein and in salt also increase Ca loss from the
body and may have an effect on oestoporosis. Post
menopausal women are more prone to osteoporosis
because they produce less oestrogen which protects
the skeleton in younger women.
Calcium Deficiency
Calcium deficiency is a condition in which the
body has an inadequate amount of calcium.
Calcium is a mineral that is essential for many
aspects of health, including the health of bones and
teeth, and a normal heart rhythm. This mineral is
also required for muscle contractions and
relaxation, nerve and hormone function, and blood
pressure regulation.
Calcium must be ingested daily and absorbed
effectively in order to maintain optimal health.
Most people can get enough calcium by eating a
variety of foods rich in calcium. Foods that
naturally contain calcium include milk and other
dairy products; green, leafy vegetables; seafood,
nuts, and dried beans. Calcium is also added to
orange juice, breakfast cereals, breads, and other
fortified food products.
High dietary calcium intake is necessary for
infants, children and adolescents in order to
promote bone growth and formation. Pregnant
women also have higher calcium needs, because it
is required for the normal development of fetal
bones. In addition, women who have reached
menopause need to ensure an adequate amount of
calcium intake to reduce the risk of osteoporosis.
Types of calcium deficiency
There are two types of calcium deficiency
 Dietary calcium deficiency is a condition
in which there is an inadequate calcium
intake, which can lead to depleted calcium
stores in the bones, thinning and
weakening of the bones, and osteoporosis.

Vol. 4 (2) Apr– Jun 2013 www.ijrpbsonline.com 662
International Journal of Research in Pharmaceutical and Biomedical Sciences
ISSN: 2229-3701
 Hypocalcemia is a low level of calcium in
the blood. It can occur from taking
medications, such as diuretics; medical
treatments; or disease processes, such as
renal failure or hypo-parathyroidism.
An insufficient amount of calcium in your diet will
generally not cause hypocalcemia. This is because
normal amounts of calcium in the blood are so
critical to many vital body functions of the nerves,
muscles, brain and heart, that your body will pull
calcium from the bones as needed to maintain
normal blood calcium levels. This enables
important processes in the body to continue.
However, ongoing dietary calcium deficiency can
eventually lead to thinning of the bones and
osteoporosis because calcium stores in the bones
are not replaced as they are used by the body.
Untreated calcium deficiency can lead to serious
complications, such as osteoporosis, hypertension
and cardiac arrhythmias and follow your treatment
plan to reduce the risk of serious complications
from calcium deficiency.If you, or someone you
are with, have chest pain a seizure, difficulty
breathing, or an unusual change in alertness or
consciousness.
Sign of Deficiency in Calcium,
All humans lose bone density starting between the
ages of 30 and 40. Excessive bone loss affects over
20 million people, mostly women who are 45 and
older.
Sign no.1: Muscle Cramping
One of the first signs of a deficiency is a nervous
affliction called tetany, which is characterized by
muscle cramps, numbness and tingling in the arms
and legs.Muscle Cramping can be an early sign that
you are developing a calcium deficiency. These
types of cramps generally occur at night, especially
in the legs
Sign no.2: Dry Skin and Brittle Nails
A common calcium deficiency sign can be seen in
your skin and your nails. When your skin becomes
dry and your fingernails become brittle (break
easily), you could be lacking from calcium. If these
symptoms are present, you may also want to check
to see if your teeth are becoming yellow. The teeth
and the bones can be severely affected from a lack
of calcium.
Sign no.3: Increased PMS Symptoms
A woman may begin experience more cramping or
a change in her menstrual flow if she is suffering
from a calcium deficiency. Adding more calcium to
a diet may ease these symptoms.
Sign no.4: Bone Fractures or Breakage
If you begin to suffer from several small bone
fractures or full bone breakage, you should really
evaluate the amount of calcium in your diet. This is
a severe symptom of calcium deficiency.
Calcium is needed to build bones and to keep them
strong. Without this calcium, our bones will
become weak. As they weaken, fractures and
breakage can occur i.e osteoporosis, in which the
bones become porous and fragile because calcium
is withdrawn from the bones and other areas faster
than it is deposited in them. Moderate cases of
calcium deficiency may lead to cramps, joint pains,
heart palpitations, increased cholesterol levels,
slow pulse rates, insomnia, impaired growth,
excessive irritability or nerves, muscle cramps,
brittle nails, eczema and numbness of the arms and
or legs.A deficiency may be due to a lack of
vitamin D or abnormal concentrations of hormones
that regulate the availability from the bones to the
blood, not to a dietary inadequacy.

Vol. 4 (2) Apr– Jun 2013 www.ijrpbsonline.com 663
International Journal of Research in Pharmaceutical and Biomedical Sciences
ISSN: 2229-3701
Regulators of Blood Calcium
Prompt diagnosis and treatment of dietary calcium
deficiency reduces the risk of developing serious
complications, such as hypertension and
osteoporosis. Treatments involve replacing the
body’s depleted calcium stores and may include:
Calcium is the most abundant mineral in the human
body and has several important functions. Calcium
is the top macro mineral when it comes to your
bones. This mineral helps build strong bones, so
you can do everything from standing up straight to
scoring that winning goal. Calcium is a primary
structural constituent of the skeleton, but it is also
widely distributed in soft tissue where it is involved
in neuromuscular, enzymatic, hormonal, and other
metabolic activity. Calcium absorption is
dependent upon the calcium needs of the body, the
foods eaten, and the amount of calcium in the foods
eaten. Vitamin D from diet or exposure to the
ultraviolet light of the sun increases calcium
absorption. Calcium absorption tends to decrease
with increased age for both men and women. More
than 99% of total body calcium is stored in the
bones and teeth where it functions to support their
structure. The remaining 1% is found throughout
the body in blood, muscle, and the fluid between
cells. Because of its biological importance, calcium
levels are carefully controlled in various
compartments of the body. The three major
regulators of blood calcium are parathyroid
hormone (PTH), vitamin D, and calcitonin.
Disorders of calcium metabolism
It occur when the body has too little or too much
calcium. The serum level of calcium is closely
regulated within a fairly limited range in the human
body. In a healthy physiology, extracellular
calcium levels are maintained within a tight range
through the actions of parathyroid hormone,
vitamin D and the calcium sensing receptor.
Disorders in calcium metabolism can lead to
hypocalcemia, decreased plasma levels of calcium
or hypercalcemia, elevated plasma calcium levels.
Hypocalcemia
Hypocalcemia is common and can occur unnoticed
with no symptoms or, in severe cases, can have
dramatic symptoms and be life-threatening.
Hypocalcemia can be parathyroid related or
Vitamin D related. Parathyroid related
hypocalcemia includes post-surgical
hypothyroidism, inherited
hypoparathyroidism,pseudohypopara thyroidism
and pseudo-pseudohypoparathyroidism. Post-
surgical hypoparathyroidism is the most common
form, and can be temporary (due to suppression of
tissue after removal of a malfunctioning gland) or
permanent, if all parathyroid tissue has been
removed. Inherited hypoparathyroidism is rare and
is due to a mutation in the calcium sensing
receptor. Pseudohypoparathyroidism is maternally
inherited and is categorized by hypocalcemia and
hyperphosphatemia. Finally, pseudo-
pseudohypoparathyroidism is paternally inherited.
Patients display normal parathyroid hormone action
in the kidney, but exhibit altered parathyroid
hormone action in the bone. Vitamin D related
hypocalcemia may be associated with a lack of
vitamin D in the diet, a lack of sufficient UV
exposure, or disturbances in renal function. Low
vitamin D in the body can lead to a lack of calcium
absorption and secondary hyperparathyroidism.
Symptoms of hypocalcemia include numbness in
fingers and toes, muscle cramps, irritability,
impaired mental capacity and muscle twitching.
Hypercalcemia
Hypercalcemia is suspected to occur in
approximately 1 in 500 adults in the general adult
population. Like hypocalcemia, hypercalcemia can
be non-severe and present with no symptoms, or it
may be severe, with life-threatening symptoms.
Hypercalcemia is most commonly caused by
hyperparathyroidism and by malignancy, and less
commonly by vitamin D intoxication, familial
hypocalciuric hypercalcemia and by sarcoidosis.
Hyperparathyroidism occurs most commonly in
postmenopausal women. Hyperparathyroidism can

Vol. 4 (2) Apr– Jun 2013 www.ijrpbsonline.com 664
International Journal of Research in Pharmaceutical and Biomedical Sciences
ISSN: 2229-3701
be caused by a tumor, or adenoma , in the
parathyroid gland or by increased levels of
parathyroid hormone due to hypocalcemia.
Approximately 10% of cancer sufferers experience
hypercalcemia due to malignancy. Hypercalcemia
occurs most commonly in breast cancer,
lymphoma, prostate cancer, thyroid cancer, lung
cancer, myeloma, and colon cancer. It may be
caused by secretion of parathyroid hormone-related
peptide by the tumor or may be a result of direct
invasion of the bone, causing calcium release.
Symptoms of hypercalcemia include anorexia,
nausea, vomiting, constipation, abdominal pain,
lethargy, depression, confusion, polyurea,
polydipsia and generalized aches and pains.
Plasma Calcium
The amount of biologically active calcium varies
with the level of serum albumin, a protein to which
calcium is bound, and therefore levels of ionized
calcium are better measures than a total calcium;
however, one can correct a total calcium if the
albumin level is known.
 A normal ionized calcium is 1.12-
1.45 mmol/L (4.54-5.61 mg/dL).
 A normal total calcium is 2.2-2.6 mmol/L
(9-10.5 mg/dl).
o Total calcium of less than 8.0 mg/dL is
hypocalcaemia, with levels below
1.59 mmol/L (6 mg/dL) generally fatal.
o Total calcium of more than 10.6 mg/dL is
hypercalcaemia, with levels over
3.753 mmol/L (15.12 mg/dL) generally
fatal.
Long-term calcium deficiency can lead to
osteopenia, which is a loss of bone density.
Osteopenia may progress into osteoporosis, a
health condition where bones become weak and
brittle. Most adults need from 1,000 to 1,200
milligrams of calcium every day. That need can be
met when you eat a balanced diet that includes
dairy products
When you don't get enough calcium over an
extended period of time, you may increase your
risk of osteopenia and osteoporosis, which in turn
increase your risk of bone fractures. But you
probably won't feel any actual symptoms of
calcium deficiency, unless you have hypocalcemia
(low blood calcium), which is usually due to health
conditions or certain medications and treatments.
The symptoms of hypocalcemia include muscle
cramps, lethargy, numbness and tingling in the
fingers, and problems with heart rhythm. These can
all be signs of other health conditions too, so if you
have them, you need to see your health care
provider.
Calcium as a Natural Tranquilizer
Calcium acts as a Natural Tranquilizer. It tends to
calm the nerves. When taken 20-40 minutes before
bedtime it promotes a deep sleep. The production
of energy and the maintenance of the immune
system benefit from calcium. By lowering
cholesterol, calcium is thought to be beneficial in
the treatment of cardiovascular disorders. Calcium
supplements up to 1500 mg have lowered blood
pressure in people with or without hypertension
and are thought to do so because of the condition of
the smooth muscle that surrounds the blood
vessels. Early supplementation may help prevent
arthritis. Rheumatism may also be helped
positively with calcium therapy. The hormones
involved are stimulated by the concentration of
calcium ions in the blood. Problems of menopause
such as nervousness, irritability, insomnia and
headaches have been overcome with administration
of calcium, magnesium and vitamin D. Prevention
of premenstrual tension and menstrual cramps has
also been noticed.Absorption takes place in the
duodenum and ceases in the lower part of the
intestinal tract when food content becomes
alkaline.
Interfering factors in absorbing Calcium
When excess amounts of fat, protein or sugar
combine with calcium an insoluble compound is
formed which cannot be absorbed. Insufficient
vitamin D intake or excess phosphorus and
magnesium hinder the absorption of calcium. Large
amounts of phytic acid present in unleavened
grains may also inhibit absorption by the
body.Other interfering factors include lack of
exercise, physical and emotional stress, excitement,
depression and too rapid a flow of food through the
intestinal tract.
The parathyroid glands in the neck help adjust the
body's storage of calcium. If these glands are not
functioning properly, accumulation may occur.
Calcium needs acid for proper assimilation. If acid
in some form is not present in the body, the mineral
will not be dissolved and therefore cannot be used
as needed by the body. Instead it may build up in
tissues or joints as deposits, leading to a variety of
disturbances. Drugs affecting absorption include
caffeine, diuretics, fatty acids, fibre oxalates,
glucocorticoids, fluoride, losec, Mylanta, protein,
thyroxine.
Absorption of Calcium and Harmone
Absorption depends upon the presence of adequate
amounts of Vitamin D, which works with the
parathyroid hormone to regulate the amount of
calcium in the blood. Phosphorus is needed in the
same amount but should not exceed the exact
amount of calcium. The body uses them together to
give firmness to the bones. If excess amounts of
either mineral is taken, that excess cannot be used
efficiently.Vitamins A & C are also necessary for
absorption. Fat content in moderate amounts,
moving slowly through the digestive tract, helps

Vol. 4 (2) Apr– Jun 2013 www.ijrpbsonline.com 665
International Journal of Research in Pharmaceutical and Biomedical Sciences
ISSN: 2229-3701
facilitate absorption as does bile and bile salts. To
function properly, Calcium must be accompanied
by magnesium, phosphorus, boron and the
Vitamins A,C,D, K and possibly E.
If the intake of calcium is too high, magnesium
levels also need to be high. Too little magnesium
results in calcium accumulations in the muscles,
heart and kidneys. Too much calcium can interfere
with the functions of the nervous and muscular
systems. An excess amount in the blood causes
calcium rigour, which is characterized by muscles
that contract and cannot relax. When an excess is
added to blood plasma, coagulation does not take
place. Too much calcium will decrease the body's
absorption of zinc and iron.
The parathyroid and thyroid glands function to control the level of blood calcium
Hormones that affect bone growth and
development include those secreted by the pituitary
gland, thyroid gland, parathyroid glands, and the
ovaries and testes . The pituitary gland, for
instance, secretes growth hormone (GH), also
called somatotropin, which stimulates activity in
the epiphyseal plates.
This hormone is the main regulator of height.
Somatotropin plays many roles in the body: it
stimulates bone and muscle growth, maintains the
normal rate of protein synthesis in all body cells,
and speeds the release of fats as an energy source
for growth. Other hormones play a part in
maintaining the strength and health of the bone
matrix by functioning to control the level of blood
calcium. In fact, calcium is needed for a number of
metabolic processes other than for bone formation,
including blood clot formation, nerve impulse
conduction, and muscle cell contraction. When a
low blood calcium condition exists, the parathyroid
glands respond by releasing parathyroid hormone
(PTH). This hormone stimulates osteoclasts to
break down bone tissue, and as a result, calcium
salts are released into the blood. On the other hand,
if the blood calcium level is excessively high, the
thyroid gland responds by releasing a hormone
called calcitonin. Its effect is opposite that of
parathyroid hormone; it inhibits osteoclast activity
allowing osteoblasts to form bone tissue. As a
result, the excessive calcium is stored in bone
matrix. The actions of these hormones are both
excellent examples of some important negative
feedback loops present in our bodies. Without
adequate supplies of these important chemicals, the
bones will not develop or grow normally.
How to prevent deficiency of Calcium
especially in Women ?
Menopausal Woman
Drop in estrogen production after menopause result
in increased bone resorption, and decreased
calcium absorption. Estrogen therapy works to
restore postmenopausal bone remodeling levels
back to those of pre-menopause, leading to a lower
rate of bone loss. Estrogen appears to interact with
supplemental calcium by increasing calcium
absorption in the gut. However, including adequate
amounts of calcium in the diet may help slow the
rate of bone loss for all women.
Amenorrheic Women and the Female Athlete
Triad
Amenorrhea is the condition when menstrual
periods stop or fail to initiate in women who are of
childbearing age. Secondary amenorrhea is the
absence of three or more consecutive menstrual
cycles after menarche occurs (first menstrual
period). The secondary type of amenorrhea can be

Vol. 4 (2) Apr– Jun 2013 www.ijrpbsonline.com 666
International Journal of Research in Pharmaceutical and Biomedical Sciences
ISSN: 2229-3701
induced by exercise in athletes and is referred to as
"athletic amenorrhea". Potential causes of athletic
amenorrhea include low body weight and low
percent body fat, rapid weight loss, sudden onset of
vigorous exercise, disordered eating and stress.
Vitamin D helps prevent calcium loss from your
bones. It is sometimes called "the sunshine
vitamin" because it is made in your skin when you
are exposed to sunlight. If you get outside in the
sunlight every day for 15 to 30 minutes, you should
get all the vitamin D you need. However, in
northern locations in winter, the sunlight may be
too weak to make vitamin D in the skin. Vitamin D
may also be obtained from your diet or from
multivitamin preparations. Most milk is fortified
with vitamin D.
CONCLUSION
A good accumulation of calcium in the bones at
early stages in life is the best prevention of age
related bone loss and fractures. it is important for
vegans to include adequate amounts of non-dairy
sources of calcium in their daily diet. It is more
efficient to take calcium in smaller doses several
times a day and at night before bedtime, which also
promotes a sound sleep. The key is prevention and
prompt diagnosis. Consult your nutritionist or
dietitian to plan your diet accordingly. Always take
away from tannin rich beverages, to help ensure
maximum absorption.
When there is not enough calcium absorbed in the
body, the output of estrogen decreases. As is the
case with postmenopausal women, older men are
often deficient in calcium. Even it also can be
encourages moderate exercise .Although dairy
products are the main source of calcium in the diet,
other foods also contribute to overall calcium
intake. Calcium is also used in muscle contraction,
blood clotting, and maintenance of cell membranes.
Long-term calcium deficiency can lead to
osteoporosis, in which it is remarkable that there
should be so much controversy over the roles of
calcium and vitamin D in human nutrition in
general and in osteoporosis in particular, given that
both are acknowledged to be essential nutrients. No
sooner have osteomalacia and osteoporosis been
satisfactorily distinguished than evidence of their
overlapping aetiologies becomes apparent. Low
calcium absorption may be the result of moderate
vitamin D insufficiency and that high calcium
excretion may be due to dietary factors (such as
protein and sodium intakes) or to hormonal effects
(such as estrogen deficiency). Seen in this light, the
worldwide pattern of osteoporosis becomes
comprehensible, but carefully targeted fieldwork -
exemplified by studies on the relationship between
calcium intake and bone density in the Gambia.
REFERENCES
1. National Research Council,
Recommended Dietary Allowances, 10th
edition.Washington, DC: National
Academy Press. 1999.
2. Olendorf D, Jeryan C and Boyden K. The
Gale Encyclopediaof Medicine.
Farmington Hills, MI: Gale
Research.1999.
3. Aaron JE, Gallagher JC, Anderson J,
Stasiak L, Longton EB and Nordin BEC.
Frequency of osteomalacia and
osteoporosis in fractures of the
proximalfemur.Lancet.1974;2:229-233.
4. Albright F, Bloomberg E, Drake T and
Sulkowitch HW. A comparisonof the
effects of A.T.10 (dihydrotachysterol) and
vitamin D on calcium
andphosphorusmetabolism in
hypoparathyroidism. J Clin
Invest.1938;17: 317-329.
5. American Journal of Medicine. Consensus
development conference: diagnosis,
prophylaxis and treatment of
osteoporosis.1993;94:646-650.
6. Baker MR, McDonnell H, Peacock M and
Nordin BEC. Plasma 25-Hydroxyl
vitamin D concentrations in patients with
fractures of the femoral neck. Br Med
J.1979;1:589.
7. Bouillon RA, Auwerx JH, Lissens WD
and Pelemans WK. Vitamin Dstatus in
the elderly: seasonal substrate deficiency
causesdihydroxycholecalciferol
deficiency. Am J Clin Nutr.1987;45:755-
763.
8. Boyce WJ and Vessey MP. Rising
incidence of fracture of the
proximalfemur. Lancet.1985;2:150-151.
9. Breslau NA, McGuireJL, Zerwekh JE
and Pak CYC. The role of dietarysodium
on renal excretion and intestinal
absorption of calcium and onvitamin
Dmetabolism. J Clin Endocrinol. Metab.
1982;55:369-373.
10. Bronner F. Intestinal calcium absorption:
mechanisms and applications. J
Nutr.1987;11: 1347-1352.
11. Carlsson A and Lindquist B. A
comparison of the intestinal and
skeletaleffect of vitamin D in relation to
dosage. Acta Physiol Scand.1955;35:53-
55.
12. Chapuy MC, Arlot ME, Duboeuf F, Brun,
J, Crouzet B, Arnaud S, Delmas PD and
Meunier PJ. Vitamin D3 and calcium to
prevent hip fractures inelderly women. N.
Engl J Med. 1992;327:1637-1642.
13. Chapuy MC, Durr E and Chapuy P. Age-
related changes in parathyroid

Vol. 4 (2) Apr– Jun 2013 www.ijrpbsonline.com 667
International Journal of Research in Pharmaceutical and Biomedical Sciences
ISSN: 2229-3701
Hormoneand 25 hydroxycholecalciferol
levels. J Gerontol.1983;38:19-22.
14. Christiansen C and Riis BJ. 17β -
Estradiol and continuous norethisterone:
aunique treatment for established
osteoporosis in elderly women. J. Clin
Endocrinol Metab., 1990;71:836-841.
15. Civitelli R, Agnusdei D, Nardi P,
Zacchei, F, Avioli LV and Gennari C.
Effects of one-year treatment with
estrogens on bone mass, intestinal
calciumabsorptionand 25-hydroxyvitamin
D-1β -hydroxylase reserve in
postmenopausalosteoporosis. Calcif
Tissue Int.1988;42:77-86.
16. Compston JE, Vedi S, Merrett AL,
Clemens TL, O'Riordan JLH and
Woodhead JS. Privational and
malabsorption metabolic bone disease:
plasmavitamin DMetabolic concentrations
and their relationship to quantitative
bonehistology. Metab Bone Dis Rel
Res.1981;3: 165-170.
17. Eddy TP. Deaths from domestic falls and
fractures. Br J Prev Soc Med.
1972;26:173-179.
18. Falch JA, Oftebro H and Haug E. Early
postmenopausal bone loss is notassociated
with a decrease in circulating levels of 25-
hydroxyvitamin D, or vitaminD-binding
protein. J Clin Endocrinol Metab.
1987;64:836-841.
19. Gallagher JC and Nordin BEC.
Oestrogens and calcium metabolism. In
P.A. Van Keep & C. Lauritzen, eds.
Ageing and estrogens: frontiers of
hormoneresearch.1973;2: 98-117.
20. Gallagher JC, Young MM and Nordin,
BEC. Effects of artificial menopause
onplasma and urine calcium and
phosphate. Clin Endocrinol. 1972;1:57-64.
21. Hartwell D, Riis BJ and Christiansen C.
Comparison of vitamin D metabolismin
early healthy and late osteoporotic
postmenopausal women. Calcif. Tissue
Int. 1990;47: 332-337.
22. Heaney RP, Recker RR, Stegman MR and
Moy AJ. Calcium absorption inwomen:
relationships to calcium intake, estrogen
status, and age. J Bone Miner Res. 1989;4:
469- 475.
23. Heaney RP, Saville PD and Recker RR.
Calcium absorption as a function of
calcium intake. J Lab Clin Med. 1975;85:
881-890.
24. Hodgkinson A, Aaron JE, Horsman A,
McLachlan MSF and Nordin BEC.
Effect of oophorectomy and calcium
deprivation on bone mass in the rat. Clin
Sci Mol Med.1978;54:439-446.
25. Horowitz M, Wishart JM, Need AG,
Morris HA and Nordin BEC. Effectsof
norethisterone on bone related
biochemical variables and forearm bone
mineralin postmenopausal osteoporosis.
Clin Endocrinol.1993;39:1-5.
26. Kanis JA and Passmore R. Calcium
supplementation of the diet. Br Med J.
1989;298:205-208.
27. Klesges RC, Ward KD, Shelton ML,
Applegate WB, Cantler ED, Palmieri
GMA, Harmon K and Davis J. Changes
in bone mineral content in maleathletes. J
Am Med Assoc.1996;276:226-230.
28. Linkswiler HM, Zemel MB, Hegsted M
and Schuette S. Protein-
inducedhypercalciuria. Fed Proc.
1981;40:2429-2433.
29. MacLaughlin J and Holick MF. Aging
decreases the capacity of humanskin to
produce vitamin D. J Clin Invest.1985;76:
1536-1538.
30. Margen S, Chu JY, Kaufman NA and
Calloway DH. Studies in
calciummetabolism -1. The calciuretic
effect of dietary protein. Am J Clin
Nutr.1974;27:584-589.
31. Marshall DH, Nordin BEC and Speed R.
Calcium, phosphorus and
magnesiumrequirement. Proc Nutr
Soc.1976;35:163-173.
32. Matsuoka LY, Wortsman J, Chen TC and
Holick MF. Compensation for
theinterracial variance in the cutaneous
synthesis of vitamin D. J Lab Clin Med.
1995;126(5):452- 457.
33. Miller SWM and Grimley EJ. Fractures
of the distal forearm in Newcastle:an
epidemiological survey. Age
Ageing.1985;14:155-158.
34. Moreiras O, Carbaja A, Perea I and Varela
MV. The influence ofdietary intake and
sunlight exposure on the vitamin D status
in an elderly Spanishgroup. Int J Vitam
Nutr Res.1992;62(4):303-307.
35. Morris HA, Need AG, Horowitz M,
O'Loughlin PD and Nordin BEC.
Calcium absorption in normal and
osteoporotic postmenopausal women.
Calcif Tissue Int. 1991;49:240-243.
36. Nordin BEC. Osteomalacia, osteoporosis
and calcium deficiency. Clin
Orthop.1960;17:235-258.
37. Nordin BEC. Calcium and osteoporosis.
Nutrition. 1997;13(7-8):664-686.
38. Nordin BEC, Baker MR, Horsman A and
Peacock MA. prospective trial ofthe
effect of vitamin D supplementation on
metacarpal bone loss in elderly women.
Am J Clin Nutr.1985;42:470-474.

Vol. 4 (2) Apr– Jun 2013 www.ijrpbsonline.com 668
International Journal of Research in Pharmaceutical and Biomedical Sciences
ISSN: 2229-3701
39. Nordin BEC, Need AG, Horowitz M
and Robertson WG. Evidence for arenal
calcium leak in postmenopausal women. J
Clin Endocrinol Metab.1991;72:401-407.
40. Prentice A. Calcium intakes and bone
densities of lactating women and breast-
fedinfants in the Gambia. Adv Exp Med
Biol.1994;352:243-255.
41. Prince RL. Counterpoint: Estrogen effects
on calcitropic hormones and
calciumhomeostasis. Endocr Rev.1994;15:
301-309.
42. Selby PL, Peacock M, Barkworth SA,
Brown WB and Taylor GA. Early effects
of ethinyloestradiol and norethisterone
treatment in postmenopausal womenon
bone resorption and calcium regulation
hormones. Clin Sci.1985;69:265-271.
43. Villareal DT, Civitelli R, Chines A and
Avioli LV. Subclinical vitamin
Ddeficiency in postmenopausal women
with low vertebral bone mass. J Clin
Endocrinol Metab. 1991;72:628-634.
44. Murphy E Williams. Hypocalcemia.
Medicine. 2009;37(9):465–468.