Needs for CalciumNeeds for Calcium Bone strengthBone strength..� Calcium as calcium phosphate constitutes 50% of bone Calcium as calcium phosphate constitutes 50% of bone

mass.mass.� An adult has about 1,000,000 mgms. Of calcium in boneAn adult has about 1,000,000 mgms. Of calcium in bone Muscle contractionMuscle contraction� Too much or too little causes tetanyToo much or too little causes tetany Nerve stimulationNerve stimulation Internal cell communication (second Internal cell communication (second

messengers)messengers)� Carries hormonal messages to the inside of the cellCarries hormonal messages to the inside of the cell

Control of Blood Control of Blood CalciumCalcium

Most accurately controlled of all blood materialMost accurately controlled of all blood material� Due to it’s many physiological rolesDue to it’s many physiological roles.. Calcium is absorbed or deposited in/from Calcium is absorbed or deposited in/from

– Intestine,Intestine,– bonebone– urineurine– soft tissuesoft tissue

Regulated by hormonesRegulated by hormones� blood increase: Parathyroid hormone (PTH) and blood increase: Parathyroid hormone (PTH) and

Vit.DVit.D

� blood decrease …..Calcitoninblood decrease …..Calcitonin

Hormone Control of Hormone Control of CalciumCalcium

Uptake of CalciumUptake of Calcium

Absorption of CalciumAbsorption of Calcium

Calcium balance: Urine: 90mgm = +ve 100mgm = 0 110 mgm = -ve

Intestinal AbsorptionIntestinal Absorption Most of the calcium intake is unavailableMost of the calcium intake is unavailable Insoluble phosphatesInsoluble phosphates Plant complexing compoundsPlant complexing compounds

– Oxalic acidOxalic acid– phytic acidphytic acid

Best source is milk or meatBest source is milk or meat– others may not be absorbedothers may not be absorbed

Need Vit D ( sun light)Need Vit D ( sun light)

Calcium BalanceCalcium Balance Calcium intake - Calcium excretionCalcium intake - Calcium excretion

� ++Ve means bones getting stronger /biggerVe means bones getting stronger /bigger� -VE means bones getting weaker-VE means bones getting weaker

Intake increased / needsIntake increased / needs Vit DVit D Calcium binding proteinsCalcium binding proteins adequate diet ( most females take 50% RDI)adequate diet ( most females take 50% RDI) Excretion increased by :Excretion increased by : inactivityinactivity high protein dietshigh protein diets caffeinecaffeine low estragon (menopause or body fat)low estragon (menopause or body fat)

Hypercalciuric Effect Hypercalciuric Effect of High Protein Dietsof High Protein Diets

Effect of AgeEffect of Age Negative balance normal after age 30-35Negative balance normal after age 30-35 Gradual loss until bones breakGradual loss until bones break OsteoporosisOsteoporosis physiological ( starts at age 35)physiological ( starts at age 35) pathogenic ( age 50 or later)pathogenic ( age 50 or later)

No way to stop lossNo way to stop loss Calcitonin treatment for agedCalcitonin treatment for aged minimised by excersise (bone stress)minimised by excersise (bone stress)

� Best protection is strong bones when Best protection is strong bones when youngyoung

OsteoporosisOsteoporosis

Susceptible IndividualsSusceptible Individuals More susceptibleMore susceptible

– Tall thin femalesTall thin females– Inactive peopleInactive people– type one diabetestype one diabetes– high protein dietshigh protein diets

Less susceptibleLess susceptible– short fat peopleshort fat people– type two diabetestype two diabetes– moderate protein dietsmoderate protein diets

Pre-diabetic individualsPre-diabetic individuals Normal individuals remove glucose from Normal individuals remove glucose from

the blood using insulinthe blood using insulin Test with Glucose Tolerance TestTest with Glucose Tolerance Test

Normal GTT means adequate insulin productionNormal GTT means adequate insulin production

Diabetes means means glucose not removed Diabetes means means glucose not removed and too much in bloodand too much in blood

– Type One No insulin producedType One No insulin produced– Type Two insulin does have effectType Two insulin does have effect– Pre-diabetics produce more insulin to produce a Pre-diabetics produce more insulin to produce a

normal Glucose Tolerance Testnormal Glucose Tolerance Test Do not show hypercaliuric effect with high protein dietsDo not show hypercaliuric effect with high protein diets

Glucose Tolerance TestGlucose Tolerance Test

Pre-diabetic GTTPre-diabetic GTT