discussing calcium element, values, use and types.

1. CALCIUMCALCIUM
Dr. Mamdouh SabryDr. Mamdouh Sabry
MD. Ain Shams, Egypt & Ph.D.MD. Ain Shams, Egypt & Ph.D.
Paris V Univ. FranceParis V Univ. France
Al Mataria Teaching Hosp.,Al Mataria Teaching Hosp.,
Nasser InstituteNasser Institute
Cairo - EGYPTCairo - EGYPT

2. • Calcium is an important source of life.Calcium is an important source of life.
• It is essential for all stages of life and in allIt is essential for all stages of life and in all
ages, from embryonic to end of life.ages, from embryonic to end of life.
• It is one of the key elements that ensuresIt is one of the key elements that ensures
healthy life.healthy life.
• Total body calcium is about 1- 1,5 kgm (2% ofTotal body calcium is about 1- 1,5 kgm (2% of
body weight).body weight).
• 99% in bone and teeth, 1% in body tissues99% in bone and teeth, 1% in body tissues
and fluids.and fluids.
CALCIUMCALCIUM

3. FunctionsFunctions
• Bone and teeth mineralization.
• Muscle contraction,
• Nerve conduction, neurotransmitter.
• Hormone release and secretion mediator.
• Blood coagulation (IV), myocardial
function
• In addition, Calcium concentration is
required for many other metabolic
processes.
• A total 109 calcium deficiency related 3

4. Metabolic processes Mediated by Calmodulin
1. Adenyl cyclase
2. Ca++
dependent protein kinases
3. CA++
-Mg++
ATPase
4. Glycerol – 3 – phosphate dehydrogenase
5. Glycogen synthetase
6. Phospholipase C
7. Phosphorylase kinase
8. Pyruvate carboxylase
9. Pyruvate dehydrogenase
10. Pyruvate kinase.

5. Natural Sources of calciumNatural Sources of calcium
. Widely distributed in food
substances such as:
oMilk, milk products
Cow milk > 1gm / 1 liter
oCheese
oEgg- yolk
oFish
oBeans
oLentils
oNuts and
oCabbage, green leaf vegetables.
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6. Intestinal Absorption of calciumIntestinal Absorption of calcium
Two mechanisms are involved:
• Simple passive diffusion
• Active transport, involving energy and calcium
pump.
o Vitamin D is important for the active process.
o Active calcium transport depends on the presence
of calbindin protein in intestinal cells, the
biosynthesis of which is totally dependent on
vitamin D.
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7. Intestinal absorption, cont.Intestinal absorption, cont.
• 30-80% of ingested calcium is absorbed,
primarily in the upper small intestine.
• Absorption is inversely proportional to amount
of calcium intake.
• If intake is low, active transcellular calcium
transport in the duodenum is increased and a
larger proportion of calcium is absorbed by the
active process compared with the passive
paracellular process that occurs in the jejunum
and ileum.
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8. Intestinal absorption, cont.Intestinal absorption, cont.
• Passive absorption in the jejunum and ileum
predominates when dietary calcium intake
is adequate or high.
• Calcium reaching the large intestine is
absorbed by active and passive processes.
• Usually, not more than 10% of total
absorption takes place in the large intestine,
but this site becomes nutritionally important
in conditions of significant small bowel
resection.09/17/18 8

9. Factors Affecting AbsorptionFactors Affecting Absorption
A) Factors favoring calcium absorption
• An acidic pH
• Presence of sugar acids, organic acids and citric acid
• High protein diet- Lysine and Arginine cause maximal
absorption
• Presence of vitamin D
• Ca : P ratio- A ratio of dietary Ca: P not more than 2:1 is
adequate for optimal absorption, ratio of less than 1:2 reduces
absorption
• State of health and intact mucosa- A healthy adult absorbs about
40% of dietary calcium.
• PTH (Parathormone) stimulates the activation of vitamin D,
thus indirectly increases absorption of vitamin D
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10. Factors Affecting Absorption, cont.Factors Affecting Absorption, cont.
B) Factors decreasing calcium absorption:
• Alkaline pH
• High fat diet- Fatty acids form calcium soaps that can not be
absorbed
• Presence of Phytates and oxalates- Insoluble calcium salts are
formed
• Dietary fiber in excess inhibits absorption
• Excess phosphates, magnesium and iron decrease absorption
• Glucocorticoids reduce intestinal absorption of calcium
• Calcitonin reduces calcium absorption indirectly by inhibiting
the activation of vitamin D
• Advancing age and intestinal inflammatory disorders inhibit
absorption of calcium
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11. Symptoms of calcium deficiency
• Osteopenia, osteoporosis, toothache, cramps,
tetany and others during pregnancy and
lactation.
• Slow growth, decrease immunity, rickets,
restlessness, sleeplessness and .. In children.
• Cramps, muscle twitching, osteopenia,
osteoporosis, fractures, tetany, insomnia,
fatigue and … in adults, middle age,
menopause and old age.

13. I.I. HormonesHormones
Factors involved in bone formationFactors involved in bone formation
(Bone Physiology)(Bone Physiology)
• ParathyroidParathyroid
resorptionresorption
• CalcitoniCalcitoni
nbuildingnbuilding
• Est. &Est. &
TestosteroneTestosterone
buildingbuilding
• Growth H.Growth H.
buildingbuilding
II.II. CellsCells
• OsteoclastsOsteoclasts
resorptionresorption
• OsteoblastsOsteoblasts
buildingbuilding
III.III. Vitamins & MineralsVitamins & Minerals
• Active Vit.Active Vit.
DD
• CalciumCalcium
• Other mineralsOther minerals
• Ca. absorptionCa. absorption • Ca. excretionCa. excretion

14. Pathophysiologic factorsPathophysiologic factors
AgeAge RaceRace Lack of estrogenLack of estrogen Body weightBody weight DiseasesDiseases
Low calciumLow calcium
Low vitamin DLow vitamin D
Excess caffeineExcess caffeine
& low calcium& low calcium
ExcessExcess
alcoholalcohol
SmokingSmoking
SedentarySedentary
HeparinHeparin AnticonvulsantsAnticonvulsants ThyroxineThyroxine CorticosteroidsCorticosteroids
DietDiet DrugsDrugs LifestyleLifestyle
Environmental factorsEnvironmental factors
OsteoporosisOsteoporosis

15. • Deficiency can occur secondary toDeficiency can occur secondary to
• Inadequate exposure to sunlightInadequate exposure to sunlight
• Sunscreens, clothingSunscreens, clothing
• Northern latitudesNorthern latitudes
• Increased melaninIncreased melanin
• AgingAging
• Decreased 7-dehydrocholesterol in skinDecreased 7-dehydrocholesterol in skin
• Inadequate dietary intakeInadequate dietary intake
• Impaired renal conversion to active vitamin DImpaired renal conversion to active vitamin D
• Intestinal resistance or diseaseIntestinal resistance or disease
• ““normal level” (>20 ng/ml or >50 nmol/L) established in 1997normal level” (>20 ng/ml or >50 nmol/L) established in 1997
• Found not high enough to optimize calcium absorptionFound not high enough to optimize calcium absorption
Vitamin D deficiencyVitamin D deficiency

16. Who Needs CalciumWho Needs Calcium
• Pregnant and lactating females >> 1500 mg / day
• Children and adolescents>> 800 – 1200 mg / day
• Middle- aged, old people>>1000--1200 mg / day
• High risk groups >>> more and more…
• ??? All age groups….
• According to WHO , the majority of people failed to take
the recommended quantity of calcium .

17. Calcium Products
• Inorganic calcium; usually calcium carbonate (
active calcium), commonest, cheapest, 40%
elemental, requires acidic media, vit. D, after
meal
• Organic calcium; calcium citrate ( 20%
elemental, empty stomach) ,gluconate, lactate,
acetate and amino acid chelated calcium,
(much less elemental calcium, each one having
undesirable effect…)

18. Adequate Ca intake is a priority for females and
males from childhood onwards
Women and men do not get their Ca needs from
diet mostly and should receive Ca suppl.
Bone building needs in addition to Ca adequate
levels of vit D, Mg & Zn, utilizing other factors

19. Thankyou
Best wishes