Mineral introduction, General functions, Classification, Macroelement of calcium , Ca- introduction, Biochemical role of calcium, recommended dietary allowance of calcium, dietary sources of calcium, Deficiency disease of calcium.

2. Minerals - Introduction
• The mineral (inorganic) elements constitute
only a small proportion of the body weight.
• There is a wide variation in their body content.
• For instance, calcium constitutes about 2% of
body weight while cobalt about 0.00004%.

3. Minerals – General Functions
• Minerals perform several vital functions
which are absolutely essential for the very
existence of the organism.
• These include:
 Calcification of bone, Blood coagulation,
 Neuromuscular irritability, Acid-base equilibrium,
 Fluid balance and Osmotic regulation.

4. Minerals – General Functions
• Certain minerals are integral components of biologically
important compounds such as hemoglobin (Fe), Thyroxine
(I), Insulin (Zn), and Vitamin B12 (Co).
• Sulfur is present in thiamine, biotin, lipoic acid and
coenzyme A.
• Several minerals participate as cofactors for enzymes in
metabolism (e.g. Mg, Mn, Cu, Zn, K).
• Some elements are essential constituents of certain
enzymes (e.g. Co, Mo, Se).

5. Minerals - Classification
• The minerals are classified as principal elements and
trace elements.
• The seven principal elements (macroelements)
constitute 60-80% of the body’s inorganic material.
• These are calcium, potassium, chloride and sulfur.
• The principal elements are required in amounts greater
than 100 mg/day.

6. Minerals - Classification
• The trace elements (microelements) are required in amounts
less than 100 mg/day. They are subdivided into three
categories.
• Essential trace elements: Iron, copper, iodine, manganese,
Zinc, molybdenum, cobalt, fluorine, selenium and chromium.
• Possibly essential trace elements: Nickel, Vanadium,
cadmium and barium.
• Non-essential trace elements: Aluminium, lead, mercury,
boron, silver, bismuth.

7. Calcium - Biochemical Role, RDA and
Deficiency Diseases

9. Calcium - Introduction
• Calcium is the most abundant among the minerals in
the body.
• The total content of calcium in an adult man is about 1
to 1.5kg.
• As much as 99% of it is present in the bones and
teeth.
• A small fraction (1%) of the calcium bound outside the
skeletal tissue, performs a wide variety of functions.

12. Calcium –Biochemical Functions
(i) Development of bones and teeth: Calcium,
along with phosphate, is required for the
formation (of Hydroxyapatite) and physical
strength of skeletal tissue I.e. bones and teeth.
(ii) Muscle contraction: Ca2+ promotes muscle
contraction.

13. Calcium – Biochemical Functions
(iii) Blood coagulation: Several reactions in the
cascade of blood clotting process are
dependent on Ca2+ (factor IV).
(iv) Nerve transmission: Ca2+ is necessary for
the transmission of nerve impulse.

14. Calcium – Biochemical Functions
(V) Membrane integrity and permeability: Ca2+
influences the membrane structure and transport
of water and several ions across it.
(vi) Activation of enzymes: Ca2+ is needed for the
direct activation of enzymes such as lipase
(pancreatic), ATPase and succinate
dehydrogenase.

15. Calcium – Daily Requirements
• Adult men and women - 800 mg/day
• Women during pregnancy,lactation and post-
menopause- 1.5 g / day.

17. Calcium - Sources
• Best sources - Milk and milk products
• Good sources- Beans, leafy vegetables, fish,
cabbage, egg yolk.

20. Calcium – Deficiency Diseases
• The blood Ca level is maintained within a
narrow range by the homeostatic control, most
predominantly by Parathyroid hormone.
• Hence abnormalities in Ca metabolism are
mainly associated with alterations in
Parathyroid Hormone.

21. Calcium – Deficiency Diseases
• Hypercalcemia
• The serum Ca level (normal 9-11 mg/dl) is elevated in hypercalcemia.
• Hypercalcemia is associated with Hyperparathyroidism caused by
increased activity of parathyroid glands.
• Decrease in serum phosphate (due to increased renal losses) and
increase in alkaline phosphatase activity are also found in
hyperparathyroidism.
• Elevation in the urinary excretion of Ca and P, often resulting in the
formation of urinary calculi, is also observed in these patients.

22. Calcium – Deficiency Diseases
• The symptoms of hypercalcemia include:
 Lethary,
 Muscle weakness,
 Loss of appetite,
 Constipation,
 Nausea,
 Increased myocardial contractility and
 Susceptility to fractures.

23. Calcium – Deficiency Diseases
• Hypocalcemia
• Hypocalcemia is a more serious and life threatening condition.
• It is characterized by a fall in the serum Ca to below 7 mg/dl, causing
tetany.
• The symptoms of tetany include neuromuscular irritability, spasms
and convulsions.
• Hypoparathyroidism is associated with a decrease in serum Ca and an
increase in serum phosphate, besides the reduced urinary excretion of
both Ca and P.

25. Calcium – Deficiency Diseases
• Rickets
• Rickets is a disorder of defective calcification of bones.
• This may be due to a dietary deficiency of Ca and P or
both.
• The concentration of serum Ca and P may be low or normal.
• An increase in the activity of Alkaline Phosphatase is a
chacteristic feature of rickets.

26. Calcium – Deficiency Diseases
• Osteoporosis
• Osteoporosis is characterized by demineralization of bone
resulting in the progressive loss of bone mass.
• Occurrence: The elderly people (over 60 yr) of both sexes
are at risk for osteoporosis. However, it more predominantly
occurs in the postmenopausal women. Osteoporosis results
in frequent bone fractures which are a major cause of
disability among the elderly.

28. Calcium – Deficiency Diseases
• Etiology: The etiology of osteoporosis is largely
unknown, but it is believed that several
causative factors may contribute to it.
• The ability to produce calcitriol from Vitamin D
is decreased with age, particularly in the
postmenopausal women.

29. Calcium – Deficiency Diseases
• Immobilized or sedendary individuals tend to
decrease bone mass while those on regular
exercise tend to increase bone mass.
• Deficiency of sex hormones ( in women) has
been implicated in the development of
osteoporosis.

30. Calcium – Deficiency Diseases
• Treatment: Estrogen administration along with
calcium supplementation ( in combination with
Vitamin D) to postmenopausal women reduces
the risk of fractures.
• Higher dietary intake of Ca (about 1.5 g/day) is
recommended for elderly people.