Higher Diloma in Hospitality Nutrition

Diploma in Hospitality Management

Nutrition Lecture Nine

Calcium

Needs for Calcium

Bone strength.

Calcium as calcium phosphate constitutes 50% of bone mass.
An adult has about 1,000,000 mgms. Of calcium in bone

Muscle contraction

Too much or too little causes tetany

Nerve stimulation

second messengers (Internal cell communication)

Carries hormonal messages to the inside of the cell

Control of Blood Calcium

Most accurately controlled of all blood chemicals

Due to it’s many physiological roles.

Calcium is absorbed or deposited in/from

Intestine, bone, urine, soft tissue

Blood Calcium is regulated by hormones

Blood calcium is increase by parathyroid hormone (PTH) acting with active Vit.D (DHCC)
Bood calcium is decreased by Calcitonin

deposites calcium in bone

Hormone Control of Calcium

Uptake of Calcium

Absorption of Calcium

Intestinal absorption

Most of the calcium intake is unavailable
Insoluble phosphates
Plant complexing compounds

Oxalic acid
phytic acid

Best source is milk or meat

tablets may not be absorbed

Need Vit D ( sun light)

Calcium Balance

Calcium intake - Calcium excretion

+Ve means bones getting stronger /bigger

-VE means bones getting weaker

Intake increased / needs

Vit D
Calcium binding proteins
adequate diet ( most females take 50% RDI)

Excretion increased by :

inactivity
high protein diets
caffeine
low estragon (menopause or body fat)

Hypercalciuric Effect of High Protein Diets

Effect of Age

Negative balance normal after age 30-35

Gradual loss until bones break

Osteoporosis

physiological ( starts at age 35)

pathogenic ( age 50 or later)

No way to stop loss

Calcitonin treatment for aged

minimised by excersise (bone stress)

Best protection is strong bones when young

Osteoporosis

Susceptible Individuals

More susceptible

Tall thin females
Inactive people
type one diabetes
high protein diets

Less susceptible

short fat people
type two diabetes
moderate protein diets
Pre-diabetic people

Pre-diabetic individuals

Normal individuals remove glucose from there blood using insulin to test if this works correctly individuals ate given a glucose tolerance test

Glucose Tolerance Test (GTT)

A normal GTT means that adequate insulin production occurs following a meal and that hyperglycemia is reduce in a normal time.
A person with diabetes does not remove glucose in good time and too much in accumulates in the blood. Glucose may then be excreted in the urine. This can be caused by two types of diabetes.

Type One No insulin produced
Type Two insulin does have effect

"Pre-diabetics" show a normal Glucose Tolerance Test but use more insulin than normal individuals to achieve this normal glucose control . Thay are not deitected with a GTT and may not know they are at risk of developing type two diabetes until it happens

I detected "pre-diabetics" by measuring there hypercaliuria following high protein diets

Pre-diabetics showed a markadly smaller hypercalciuric effect than normal individuals.
I identified these individuals when they were in their 20’s

Glucose Tolerance Test

Pre-diabetic GTT

Postprandial Calciuric Effect of Pre-diabetic individuals (hyperinsulaemic)

The End

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