Calcium Deficiency Causes, Effects, And Treatment.

Calcium is the most abundant cation in the body and powerful homeostatic mechanisms control circulating ionized calcium levels. In this article will see Calcium deficiency causes, effects, and treatment.

A normal adult body contains about 1 kg of calcium, of which approximately 99% is present in the skeleton as hydroxyapatite [Ca10 (PO4)6(OH) 2] and 1% in soft tissues and extracellular fluids.

In spite of large movements of calcium between body compartments, serum calcium is maintained constant at about 10 mg/dl (2.5 mg).

The essential fraction is the biologically active free, ionized one which equals 50% of the total serum calcium (1.3 mg).

Forty percent of total serum calcium is protein-bound, principally to albumin. Remaining 10% of calcium is complexed with various anions such as nitrate, sulfate, bicarbonate, lactate, and phosphate.

A decrease in serum albumin of 1 g/dl results in a decrease in total serum calcium of 0.8 mg/dl without affecting the ionized fraction significantly.

World Health Organization (WHO) dietary guidelines for calcium differ between countries, with higher intakes usually recommended in places with higher fracture prevalence.

In the diet, 20% to 30% of calcium is absorbed. It depending on vitamin D status and food source. Calcium requirements depend on phosphorus intakes with an optimum molar ratio (Ca:P) of 1:1.

Calcium Sources to Reduce Calcium Deficiency.

Seaweeds
Soya drinks fortified with calcium
Bread, fortified with calcium any other products of flour
Crushed eggshell

Calcium Absorption in The Body

Important cellular functions of calcium.

Cell division.
Cell adhesion.
The integrity of the plasma membrane
Muscle contraction
Neuronal excitability.
Secretion of proteins.
Coagulation cascade.

Absorption of calcium takes place in the small intestine through two processes:-

Passive paracellular pathway:-

The paracellular pathway is dependent on calcium moving through tight junctions in the intestinal epithelium. This is a passive, nonsaturable process and is favored during states of high calcium intake.

Active transcellular pathway:-

The transcellular pathway is an active transport which is particularly important at low and normal calcium intake. In intestinal absorption of Ca2+ via the transcellular pathway, Ca2+ enters through Ca2+ channel TrPV5 or TrPV6, in the luminal membrane of the enterocyte (RBC).

Once absorbed, the transcellular movement of calcium to the basolateral membrane is dependent on binding to an intracellular protein known as calbindin-D9k.

The egress of calcium from the intestinal epithelium occurs through the actions of the plasma membrane calcium-dependent ATPase (PMCA1b).

This transcellular movement of calcium is closely regulated by 1,25(OH)2D3. It regulates the gene transcription of TRPV6, calbindin, and PMCA1b.

How Much Calcium Do We Need?

Children between 1- 9 years of age- 700-1300mg/day
Teenagers between 13-18 years of age- 1300mg/day
Premenopausal women, 25-50 years of age and post-menopausal women’s depend upon estrogen replacement therapy- 1000-1200 mg/day
Women above 65 years of age and those who are not on estrogen replacement therapy- 1500mg/day
Pregnant and lactating women’s- 1500mg/day
For men’s between 25-65 years of age- 1000mg/day
All people (both men’s and women’s) above the age of 65- 1500mg/day

Important Role Of Calcium in Our Body

Building up stronger bones and teeth.
Regulating muscular contractions
Controls the muscular contraction of the heart including heartbeat
Controlling the blood clots

Plays an important role in various cellular functions. Also in the activation of certain enzymes, without the presence of calcium, they are inactive.

Note:- Calcium does not absorb without vitamin D.