ArticlePDF Available

Calcium and its Role in Human Body

  • Y.C. Institute of Science Satara


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.
Vol. 4 (2) Apr– Jun 2013 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.
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
Key Words: Calcium, Oesteoporosis, Hypo and Hypercalcaemia, Parathyroid glands.
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 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).
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
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
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 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
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
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 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
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
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 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 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 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 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
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
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
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,
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 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
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 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.
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.
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
3. Aaron JE, Gallagher JC, Anderson J,
Stasiak L, Longton EB and Nordin BEC.
Frequency of osteomalacia and
osteoporosis in fractures of the
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
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
7. Bouillon RA, Auwerx JH, Lissens WD
and Pelemans WK. Vitamin Dstatus in
the elderly: seasonal substrate deficiency
deficiency. Am J Clin Nutr.1987;45:755-
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.
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-
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 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.
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.
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:
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.
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.
29. MacLaughlin J and Holick MF. Aging
decreases the capacity of humanskin to
produce vitamin D. J Clin Invest.1985;76:
30. Margen S, Chu JY, Kaufman NA and
Calloway DH. Studies in
calciummetabolism -1. The calciuretic
effect of dietary protein. Am J Clin
31. Marshall DH, Nordin BEC and Speed R.
Calcium, phosphorus and
magnesiumrequirement. Proc Nutr
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
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
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 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
41. Prince RL. Counterpoint: Estrogen effects
on calcitropic hormones and
calciumhomeostasis. Endocr Rev.1994;15:
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.
... It plays a huge function inactivation of enzymes such as adenosine triphosphatase (ATPase), succinic dehydrogenase, lipase, etc. [6]. The demand for calcium is highest during the period of growth such as childhood, and other physiological states such as pregnancy and lactation [12]. Mainly, calcium makes up 920 to 1200 grams of adult body (i.e., about 1.5% of body weight) weight, with 99% found in bones and teeth and 1% in serum [1]. ...
... On estimate, the recommended daily allowance for calcium is reported between 700-1300 mg per day [13,14]. Depending on the physiological status of the body, an adult may require about 10 mg of calcium per kilogram of body weight [12]. For instance, pregnant and lactating women may require higher calcium intake due to the rapid depletion of calcium because of their status [12]. ...
... Depending on the physiological status of the body, an adult may require about 10 mg of calcium per kilogram of body weight [12]. For instance, pregnant and lactating women may require higher calcium intake due to the rapid depletion of calcium because of their status [12]. ...
Full-text available
Minerals are chemical elements that organisms require as a necessary nutrient to sustain good health at various stages of life. To support human biochemical processes, including structural and functional activity in the body, at least twenty mineral elements are required. However, inadequate consumption of these essential minerals in the human diet can result in metabolic problems, organ damage, chronic diseases, and death. Mineral deficiency affects roughly two billion people globally, the bulk of whom live in third-world nations. Among those, infants and pregnant women are more susceptible to the mineral shortage in the body. To avoid these deficiencies, humans need to consume muscle foods, which are superior sources of essential minerals, particularly zinc, selenium, phosphorus, iron, etc. compared to plant-based foods. Minerals derived from muscle foods are easier to absorb in the body than minerals derived from plant foods. However, the amount of essential minerals in muscle foods varies widely and depends on several factors, including nutrition, species, breed, sex, age at slaughter, muscle types, physiological status, production system, and post-mortem factors such as processing and analytical methods. The present study discusses the mineral composition of different muscle foods, factors affecting the mineral contents in different muscle foods and the beneficial and important roles that minerals play in human health.
... Although, dietary calcium deficiency can lead to osteoporosis and thinning of the bones over time. The carelessness in treatment of calcium deficiency can move to some critical complications, such as hypertension, osteopenia, and cardiac arrhythmias (Piste, Sayaji, & Avinash, 2012). If you, or someone you are with, have chest pain, a seizure, difficulty breathing, or an unusual change in alertness or consciousness,then you should consider getting your calcium checked. ...
... Average calcium deficiency cases may lead to heart palpitations, cramps, increased cholesterol levels, joint pains, insomnia, slow pulse rates,excessive irritability, impaired growth, or nerves, brittle nails, muscle cramps, eczema and numbness in arms and legs (Piste, Sayaji, & Avinash, 2012). Insufficiency might be due to an unavailability of vitamin D or abnormal concentrations of hormones that regulate the availability from the bones to the blood, not to a dietary inadequacy. ...
... 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 preserved in the bone matrix (Piste, Sayaji, & Avinash, 2012). The works of these hormones are an amazing example of important negative feedback loops in our bodies. ...
Full-text available
Peanuts are considered as one of the rich sources of healthy nutrition. India is among the major producers of peanuts in the world but ironically, India also has the largest number of malnourished people. In such a case, consumption of peanuts can be extremely advantageous. Allergies from peanuts are consonantly less widespread in India. Peanut is employed in many traditional dishes within the country through the schemes of Midday meal and on the lines of plumpy nuts, the undernourished are often fed and the dual burden of malnutrition and overweight can be reduced. Thus, dual outlook of appreciable industrialisation and organisational creativity of peanut products can create a healthy population. It is for sure, that there's an enormous extent for the industrialisation of peanut products. Hence, the market mania looks extremely hopeful due to these footnoted factors. Further, peanuts can reduce the daily use of unwanted supplementation from non-dietary roots. Chickpeas (also referred as garbanzo beans) are referred as one of the earliest eaten crops within the world and hang in the air today, nearly in every continent. Chickpeas are the part of many long-established diets for more than 7,500 years. Still, they are included in the diets of the healthiest populations living around the world today, counting those who eat traditional cuisines that rise from the centre east side, the Mediterranean sea region and African tribes too. Next to the soyabean, chickpeas is the bean generally grown and eaten worldwide. Chickpeas are a kind of legume that gives so many health benefits. Chickpeas also helps to extend satiety, fasten digestion, manage blood glucose levels, increase the body's ability to fight against diseases and many more such benefits. Chickpeas are nutritionally dense, packaged with lots of proteins, vitamins and minerals, which is one of the reasons why they are specifically included in various healing diets. In the present scenario, lifestyle changes which incorporate mimicking westernisation, sedentary lifestyle, calorie and meal over-intake, increase fluoride content in soil and water, and drug interplay/medicine, along with reduced physical activity are causing a lot of nutrient deficiency. But mostly, it affects the calcium and vitamin D status in humans, which results in diseases like fluorosis, rickets, osteopenia and osteoporosis. During the study total 60 subjects (17-25 years women) were undertaken in which along with their normal diets, 20 subjects were on peanuts, 20 were on chickpeas and remaining 20 were on placebo. To compare the effect on serum calcium levels this study was done over a period of 60 days with regular monitoring and counselling done during this period. As the study was not completed due to the COVID-19 pandemic, the results should reveal that there was not much significant difference in the serum calcium levels. But the subjects who were taking chickpeas showed some significant differences than those with peanuts and placebo along with the diet because it was a short period of research. If the duration of study would have been for long, probability of getting higher significance results. Therefore, it can be concluded that chickpeas have a higher role than peanuts in increasing the serum calcium levels of a person over a short period of time.
... Calcium is very essential in muscle contraction, building strong bones and teeth, blood clotting, nerve impulse, transmission and regulating heart beat and fluid balance within cells. The requirements are greatest during the period of growth such as childhood, during pregnancy and when breast feeding (Pravina et al., 2013), so it can be considered that providing palatable bakery products by using natural sources for fortification such as date molasses is one of the good ways to help people suffering from a lack of calcium. Because the presence of phosphorus in both corn and rice flour is higher than that of date molasses Table 2., when the percentage of addition of date molasses raised, a decrease in the phosphorous percentage appears, (Figures 2, 3, 4 and 5). ...
... Calcium is very essential in muscle contraction, building strong bones and teeth, blood clotting, nerve impulse, transmission and regulating heartbeat and fluid balance within cells. The requirements are greatest during the period of growth such as childhood, during pregnancy and when breast feeding (Pravina et al., 2013). So, it can be considered that providing palatable bakery products by using natural sources for fortification such as date molasses is one of the good ways to help people suffering from a lack of calcium. ...
... Potassium is required to maintain the osmotic balance of the body fluids and control glucose absorption [71]. The calcium helps in strong teeth and bone formation [72]. TWB had the highest calcium which could as a result of the percentage of AYB added. ...
... Hypocalcemia, or calcium deficiency, can cause decreased bone and muscle mass. Diseases like osteoporosis and rickets, which negatively affect bone density, are caused mainly by hypocalcemia (3). Calcium deficiencies are especially prevalent in developing tropical and subtropical countries, where the estimated calcium intake of children is between ⅓ and ½ of the recommended daily intake (4). ...
Micronutrient deficiencies, which affect more than two billion people globally, occur when an individual does not receive adequate amounts of essential vitamins or minerals. Biofortification aims to increase the nutritional content of food crops, and it is an important tool in decreasing the effects of micronutrient deficiencies. Specifically, hypocalcemia, or calcium deficiency, causes a wide range of symptoms that affect many different body systems. In this study, we tested the hypothesis that increasing the amount of calcium available to the food crop during growth would increase the amount of calcium present in the food crop. A total of 180 radish (Raphanus sativus) plants were grown in a controlled environment and irrigated with water of varying Ca2+ concentrations. The height of each plant was measured every five days beginning at day 0 to track the growth. At maturity, a random sample of four plants from each group were tested for calcium and magnesium content using an atomic absorption spectrophotometer. The group that received the highest concentration of Ca2+ grew significantly smaller than most other groups. The Ca2+ contents of leaf samples had no significant difference in Ca2+ or Mg2+ content; however, the Ca2+ content of root samples showed a significant decrease from the control in both Ca2+ and Mg2+ content across several experimental groups. These results provide preliminary evidence that irrigation with Ca2+ solutions does not increase the calcium content of mature plants, but further testing is needed to confirm these results. If increased calcium in irrigation water significantly increases the calcium content of mature radish plants, this technique could be used to increase the calcium content of other crops in areas with high rates of hypocalcemia.
In the context of nutrition, minerals are classified as the inorganic chemicals required by living organisms. Four essential elements carbon, hydrogen, oxygen, and nitrogen that are present in nearly all biomolecules constitute 96% of the body mass. Apart from these 4 elements, the body also contains 20 other minerals which make up less than 4% of the body weight but are equally important. The human body uses minerals for a variety of physiological functions such as maintenance of skeletal mass, muscular contraction, neural functions, and as important components of many enzymes and hormones. None of the minerals can be synthesised in the body and hence need to be consumed in the diet. A variety of minerals are found in a range of foods, many of which are metals like iron, copper, and zinc, and some are non-metals, such as calcium, iodine, and fluorine. Hence the term “mineral” is actually a misnomer since it is used to simply describe the less common inorganic elements in the diet.
Full-text available
This study aimed to determine the effect of dairy products consumption and certain physical activities on bone mineral density (BMD) and mass index (BMI) as rates for osteoporosis and obesity used. BMI was classified as underweight (<18.5 BMI), normal weight (18.5-24.9 BMI), overweight (25-24.9 BMI), Overweight (25-29.9 BMI) and obese (˃ 30 BMI) are considered as the obesity degree. BMD was measured for the right foot using a pDEXA densitometer with dual-energy X-ray absorptiometry (DXA) and expressed as a T-score then subdivided as normal (T ≥ 1), osteopenia (T (-1)-(-2.5)) and osteoporosis (T <-2.5). The correlation was performed using Pearson's correlation coefficient formula. The results showed that mean BMI, BMD, and milk product consumption were 27.3 ± 0.98, 0.79 ± 0.76, and 62 ± 0.43, respectively. Results showed that most respondents were consuming insufficient amounts of dairy products, leading to high rates of osteoporosis (21%) and osteopenia (37%). The correlation value of physical activity was negative with BMI (-0.073) and positive with BMD (0.053). The results showed that dairy consumption and daily physical activity can increase bone mineral density and prevent obesity.
Calcium is an essential skeletal mineral, and calcium deficiency has a negative impact on bone health. We conducted an online questionnaire to assess the intake and knowledge among the Saudi population. The survey included 950 participants, with 51.1% demonstrating poor knowledge of calcium sources and a mean intake lower than the recommended level. Calcium is an essential mineral and one of the most prevalent in the body. Chronic insufficient calcium intake increases the risk of osteopenia, osteoporosis, and bone fracture. This study aimed to assess the Saudi population’s calcium intake and knowledge of calcium sources as well as to identify factors associated with inadequate calcium intake. This cross-sectional study was conducted across Saudi Arabia using an online questionnaire distributed randomly through social media channels. The questionnaire was a validated tool that was previously developed and used by the original author to assess knowledge of calcium food sources and estimate calcium intake in the Saudi population. If an individual answered more than 11 questions correctly, calcium knowledge was considered adequate. Calcium intake was considered sufficient or insufficient based on the recommended dietary allowance (RDA) of 1000 mg/day. The survey included male and female Saudi citizens and residents aged 14 years or older. A total of 950 respondents aged 9–70 completed the questionnaire. A total of 62.9% of the respondents were 26–50 years old. Of the participants, 64.2% were female, 71.7% were married, and 61.9% had a diploma or a bachelor’s degree. Of these, 63.8% were from the central region, and 97.6% were from Saudi Arabia. For those aged 9–18, the average calcium consumption was 577 mg/day, whereas it was 479 mg/day for those aged 19–50. The average intake was 479 mg/day for males aged 51–70 (EAR = 1000 mg/day) and 438 mg/day for females (EAR = 1200 mg/day). These calcium consumption values were significantly lower than the estimated average requirement (EAR) and RDA (p < 0.01). Correct response rates for the 19 calcium intake knowledge items ranged from 23.4 to 94.7%. Among the participants, 48.9% had significant calcium intake knowledge, as indicated by a score of > 11 out of 19 correct responses. Age, sex, marital status, educational attainment, and residence were significantly correlated with adequate knowledge of calcium. Demographic characteristics such as age, marital status, and residence were associated with sufficient calcium intake in the study. The study findings revealed that a significant proportion (51.1%) of participants demonstrated inadequate knowledge regarding calcium food sources. Additionally, the mean calcium intake was found to be lower than the RDA of 1300 mg/day for males and females 14–18 years old and 1000 mg/day for males and females 19–50 years old and males 51–70 years old; however, the RDA for females 51–70 years old is 1200 mg/day, suggesting an urgent need for interventions aimed at enhancing both calcium knowledge and intake.
Hourly fractional absorption of radiocalcium (alpha), serum calcitriol, and a number of other variables were measured in 152 normal and 148 osteoporotic postmenopausal women. Alpha, body weight, and serum albumin were all significantly lower in the osteoporotic than in the normal women, and plasma alkaline phosphatase, fasting urinary calcium, sodium, and hydroxyproline were all significantly higher in the osteoporotic than in the normal group. The most significant determinant of alpha in each group was the serum calcitriol concentration, but calcium absorption relative to serum calcitriol was significantly lower in the osteoporotic than in the normal women. The serum calcitriol level was slightly but not significantly lower in the osteoporotic than in the normal group and accounted for only 20% of the difference in alpha between them. The implied “resistance” to calcitriol in the osteoporotic group was significantly related to serum albumin and body weight but independent of age. Urinary hydroxyproline was an inverse function of alpha and a positive function of fasting urinary calcium in the osteoporotic group.
1. The effects of a low calcium diet and of oophorectomy, separately and together, on cortical and trabecular bone mass, have been examined in mature female rats. 2. Calcium deprivation caused a significant decrease of weight, cortical cross-sectional area and ratio of cortical to total area in the femur, it significantly reduced the volume of trabecular bone and increased the percentage of osteoid surface in the tail vertebrae, and in addition increased the urinary excretion of phosphate and, initially, of hydroxyproline. 3. Oophorectomy caused similar though smaller changes in trabecular bone and urine, whereas the effects of oophorectomy on cortical bone were greater on a low calcium intake than on a normal intake. 4. The ash weight of the femora, expressed as a percentage of the total dry weight, was unaffected by calcium deprivation or oophorectomy alone but was significantly reduced when the two occurred together. 5. The percentage of resorption surfaces in the vertebrae tended to increase on the low calcium diet and after oophorectomy on the normal diet but decreased after oophorectomy on a low calcium diet. 6. It is concluded that oophorectomy and calcium deficiency each reduce bone mass in the adult rat but the greatest effect is seen when they are combined.
The relationships between the amount of calcium absorbed and the quantity ingested was evaluated in 180 adult humans. Absorption was measured from the concentration ratio of concurrently administered oral and intravenous calcium isotopes. Intake ranged from 0.163 to 7.48 Gm. Ca per day. In 14 subjects, intakes were artificially elevated for purposes of this study. All others were studied at their usual intake levels. Absorption (Ca Abs) was found to follow a curvillnear relationship with intake (Ca-D), and was characterized by the following equation: Ca Abs equals 0.1541 - Ca-D plus 0.3127[exp(-1.0539 - Ca-D)] - Ca-D. The exponential term of this equation provided the major component of total absorption at intakes below 0.8 Gm. per day, but fell to negligible values when intake reached 2 to 3 Gm. per day, above which absorption was characterized by a simple linear function of intake. We found that there was no detectable upper limit to absorption capacity, which, at the 7.48 Gm. intake level, averaged more than 1.0 Gm per day. The observed mathematical description is consistent with the generally recognized inverse relationship between absorption efficiency and intake. At the same time it indicates that a component of absorption is independent of control mechanisms and is related solely to intake. A more general form of the foregoing equation, suggesting provision for other physiological variables such as growth hormone and cortisol, is proposed and discussed.
Traditional dietary habits and the living style in Spain should theoretically be enough to assure a healthy vitamin D status: a very high fish intake and one of the highest sun exposure rates of all countries in Europe. However, in spite of this, there is a high percentage in the elderly showing low vitamin D serum values. This paper is part of the Euronut-SENECA study, a major multicentre survey assessing the nutritional status in the elderly from 19 centres over 12 countries in Europe. In it, the vitamin D status in 55 healthy individuals from Spain has been studied and assessed by measuring dietary and supplemental vitamin D intakes; the influence of sunlight exposure such as physical activity, permanence in the sun, clothing, etc.; and 25-hydroxyvitamin D [25 (OH)D] serum concentration. The mean dietary intake was 1.3 +/- 1.5 micrograms/day, being fish, and specially fatty fish, the main source (62%). Of the total, 85% of the elderly did not reach the Spanish recommended dietary intake (2.5 micrograms/day). The mean 25(OH)D serum level was 25 +/- 14.7 nmol/l and there was a high percentage with deficit (13%) (8.4 +/- 1.9 nmol/l) and marginal (62%) (19.8 +/- 4.2 nmol/l) levels. People who usually walked 1.9 +/- 1.3 hours/day or stayed in the sun "every day" or "as much as possible", had higher (p < 0.05) serum 25 (OH)D concentrations (27.7 +/- 2.4 nmol/l and 31.3 +/- 3.7 nmol/l, respectively) than people who did not (16.6 +/- 1.2 nmol/l and 21.3 +/- 2.1 nmol/l, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)