Calcium & factors affecting absortion of it

1. ROSHNI MAURYA

2.  Calcium is the “earth alkali”
mineral found in earth’s crust,
usually as fairly soluble salts.
The word calcium comes from
Latin calc, meaning ‘lime’ as in limestone,a
calcium carbonate substance.

3.  ATOMIC NUMBER: 20
 ATOMIC SYMBOL: Ca
 ATOMIC WEIGTH: 40.08
 ELECTRONIC CONFIGURATION:[Ar]4s2
 ATOMIC RADIUS: 197.3pm
 MELTING POINT: 842 0C
 BOILING POINT : 1484 0C
 OXIDATION STATE: 2

4. • Fifth most abundant element in biosphere
– (After iron, aluminum, silicon, and oxygen)
• Made from calcium:
– Limestone and marble
– Coral and pearls
– Sea shells and egg shells
– Antlers and bones
• Found in rocks, seawater, fresh water, soils
• Land living mammals: 2-4% of gross body
weight

5.  99 % of the body’s calcium is stored in bone as hydroxyapatite
 Second reservoir is intracellular calcium
o Low concentration in cytosol when cell is inactive
o Stored bound to proteins in mitochondria
o Endoplasmic reticulum
 Smallest reservoir in extra-cellular fluid
o Most important to regulate circulatory concentrations
Figure 17-1. Generalities about calcium

6. Calcium deposits in damaged tissue
Occurs with advancing age
Found in atherosclerotic plaques in arteries
Scar tissue from disease or injury
Not caused by dietary calcium
Caused by tendency of calcium to bind with
proteins
Calcification of tissue (other than bones and teeth) is
sign of tissue damage and death
As in end-stage kidney disease

7.  Calcium is the most abundant mineral in human body and is essential to:
 Bone health
 Cardiovascular health
 Muscle maintenance
 Circulatory health
 Blood clotting
 Acts as an enzyme activator

8.  Recommended Daily Intake
 •Infants- 600-900mg•
Adults- 400-500mg•
Pregnancy and lactation-1000-1200mg
 Extra calcium is needed in
 Menopausal Woman
 Amenorrheic Women and the Female Athlete
Triad
 Lactose Intolerant Individuals
 Vegetarians

10.  Plasma calcium :
 Normal level -9-11mg/dl .
 50% - present as ionized form.(biologically active)
 40% - bound to proteins i.e. albumin.(non-diffusible Ca)
 10% - complexed calcium –calcium citrate, bicarbonate and phosphate.(diffusible)
 •Ca X P in serum
 children – 50 and adults 30-40.
 •Calcium: Phosphate ratio in diet:
 During growth – 1:1
 After cessation of growth- 1: 2.

11.  RICH SOURCES OF CALCIUM
 Dairy Products, such as Milk, Cheese, and Yogurt•
 Canned Salmon and Sardines with Bones
 Leafy Green Vegetables, such as Broccoli, Spinach
 Calcium-Fortified foods - from Orange juice to Cereals and
Crackers Ice Cream, Oysters, Ricotta.
 CALCIUM BALANCE:
 It is the net gain or loss of calcium by body over a specific period
of time.
Amount absorbed = Amount ingested - Amount egested in faeces
 Amount retained = Amount absorbed –Urinary calcium(excreted)

12. Food Portion Calcium
(mgs.)
Swiss cheese 2 oz. 530
Jack cheese 2 oz. 420
Cheddar cheese 2 oz 400
Other cheeses 2 oz. 300–400
Yogurt 6 oz. 300
Broccoli, cooked 2 stalks 250
Sardines (w/bones) 2 oz. 240
Goat milk 6 oz. 240
Cow’s milk 6 oz. 225
Collard greens, cooked 6 oz. 225
Turnip greens, cooked 6 oz. 220
Almonds 3 oz. 210
Brazil nuts 3 oz. 160
Calcium Sources
Soybeans, cooked 6 oz. 150
Molasses,blackstr
ap 1 Tbl. 130
Corn tortillas (4,
w/lime) 2 oz. 125
Carob flour 2 oz. 110
Tofu 3 oz. 110
Dried figs 3 oz. 100
Dried apricots 3 oz. 80
Parsley 1½ oz. 80
Kelp ¼ oz. 80
Sunflower seeds 2 oz. 80
Sesame seeds 2 oz. 75

13.  It is regulated by :
 PTH and 1,25-(OH)2D3 on gut, kidney and
bone
 Calcium receptors:
 are present in the parathyroid gland, kidney ,
brain and other organs.

15.  The active form of vitamin D is 1,25-
dihydroxycholecalcififerol(Calcitriol). Its
production in the kidney is catalyzed by 1 a-
hydroxylase .
1 a-hydroxylase activity is by :
 Decreased serum Ca2+
 Increased PTH level
 Decreased serum phosphate

16. Vitamin D allows calcium to capture good bone. (A bone below left), increasing
calcium absorption from the intestine. (A coil intestine below the middle), and help
prevent loss of calcium to the kidney. (A similar red beans Luang below right).
Path life of vitamin D is absorbed from the intestine (Gastrointestinal), live sunlight
helps the skin processing, after processing requiring additional time is 2 to liver and
kidney.

17.  Increases intestinal Ca2+ absorption
 Incases intestinal phosphate absorption
 Increase renal reabsorption of Ca2+ and
phosphate
 Increases resorption of bone

18.  Eat more swordfish, bluefish, salmon, mackerel, or sardines. But
swordfish and some species of mackerel are on the list of fish with high
mercury levels, so don’t go overboard.
 Take a calcium supplement that includes vitamin D. Many brands
combine calcium with 200–400 IU of vitamin D.
 Take a multivitamin. Multivitamins are a safety net for many nutrients
that might otherwise fall through the cracks. Most brands contain 400
IU of vitamin D.
 Spend more time outdoors. This is a balancing act, because you don’t
want to risk skin cancer in pursuit of more vitamin D production.

19.  it is an 84-amino-acid hormone.
Secretion:
 from the chief cells of the
parathyroid glands.
Function:
increase renal phosphate excretion , and increases plasma
calcium by:
 Increasing osteoclastic resorption of bone (occurring rapidly).
 Increasing intestinal absorption of calcium (a slower
response).
 Increasing synthesis of 1,25-(OH)2D3 (stimulating GIT
absorption).
 Increasing renal tubular reabsorption of calcium

20.  Low serum [Ca+2]  Increased PTH secretion
 High serum [Ca+2]  Decreased PTH secretion

21. Produced by :
 thyroid C cell.
Function:
 Inhibition of osteoclastic bone resorption .
 Increasing the renal excretion of calcium and
phosphate.

24. ◦ Transcellular: active transport involving a calcium
binding protein, calbindin
 Stimulates calbindin
◦ Paracellular: by diffusion
 A function of calcium content of chyme
◦ Most absorption in ileum
◦ 1,25(OH)2D stimulates synthesis of calbindin in
gut cells
◦ Calbindin can bind 2 Ca2+ per molecule
Calcium dependent ATP pump moves calcium into
extracellular fluid against the electochemical gradient

25.  Ca is not absorbed well in an alkaline medium
as it is less soluble
 Best taken between meals or in absence of
food when stomach is more acidic
 Taking Ca with vit.D & xtra HCl absorption
 Supplements of ca or of Ca &Mg are often
taken at night be4 bed to help absorption
and to prevent the xtra loss of body ca that
can during night,ca &Mg is a good evening
tranquilizer.

26.  Recently,trace min.boron has been shown to
help in ca utilization and bone health.
 Form in which ca is supplied is also
important.Most highly recommended is
aspartate or citrate salts of ca,chelated ca
with aa, ca gluconate,followed by CaCO3 &
lactate-all are absorbable sources.

27.  Increased by:
 Body needs—growth,
pregnancy, lactation
 Vitamin D
 Milk lactose
 Acid environment—
hydrochloric acid, citric
acid, ascorbic acid (vitamin
C)
 Protein intake and amino
acids such as lysine and
glycine
 Fat intake
 Exercise
 Phosphorus balance
 Decreased by:
 Vitamin D deficiency
 Gastrointestinal problems
 Hypochlorhydria (low
stomach acid)
 Stress
 Lack of exercise
 High fat intake
 High protein intake
 Oxalic acid foods (beet
greens, chard, spinach,
rhubarb, cocoa)
 Phytic acid foods (whole
grains)
 High phosphorus intake

28.  Calcium supplements usually come in 500- to 600-mg tablets. You don’t
absorb large doses of calcium as efficiently as you do small ones. Thus, much
of a 1,000-mg tablet is going to waste, although unabsorbed calcium in the
gut may have benefits. Taking a regular-size pill with calcium-fortified orange
juice might also be a waste.
 The calcium in most supplements is either in the form of calcium carbonate or
calcium citrate. Research shows that they are absorbed equally well with
meals, but calcium carbonate is harder to digest than calcium citrate. People
are usually advised to take calcium carbonate with or soon after a meal.
Calcium citrate can be taken at any time.
 Most multivitamin pills contain a relatively small amount of calcium — about 100–
200 mg.
 AlgaeCal is the world’s only plant source of Ca, so it is bio available pre-digested
minerals . It also includes Mg trace minerals, vit.D3 & k2 at full dosages.

29.  Acid rebound. Calcium carbonate may cause acid rebound: the stomach overcompensates for
the high dose of calcium carbonate, which is alkaline, by churning out more acid. For that reason,
people with a history of stomach ulcers are advised that they may not tolerate it and may have to
switch to calcium citrate.
 Constipation. Calcium supplements can have a mild binding effect but by themselves don’t usually
cause serious constipation. But if you’re taking another supplement or medication that binds the stool,
the addition of calcium supplements could cause a problem.
 Too much calcium. Although it doesn’t happen often, some people have taken so much calcium that it
causes hypercalcemia, an above-normal level of calcium in the blood. Hypercalcemia may cause
nausea, vomiting, confusion, and other neurological symptoms.
 Drug interactions. Large doses of calcium interfere with the absorption of a variety of drugs. You
should avoid consuming large amounts of calcium — either in food or as a supplement — within 2–4
hours of taking a tetracycline or quinolone antibiotic. After taking alendronate (Fosamax), risedronate
(Actonel), or another one of the bisphosphonate drugs for osteoporosis, you should wait at least 30
minutes before consuming a large amount of calcium. People taking calcium-channel blockers or beta
blockers should discuss taking calcium with their doctors because it can reduce the effectiveness of
these drugs.

30. It refers to the amount of Ca eliminated from the body in urine;feces and sweat.
 Renal threshold forserum Ca is 10 mg/dl .
 FACTORS:
 Typically,dietary Na & protein s ca excretionas the amt. of their intake is sd . However, if
a high protein, high sodium food also containsCa, this may help counteractthe loss of Ca .
 ing dietarypotassium intake in the presence of a high Na diet may help Ca excretion,
particularly in postmenopausal women . intake of Na .
 Caffeine can temporarily Ca excretionand may modestly Ca absorption, an effect easily
offset ing Ca consumptionin the diet .
 Alcohol can affect Ca status by reducing intestinal absorption. It can also inhibit enzymes in
the liver that help convert vitamin D to its active form which in turn reducesCa absorption .

31. Deficiency of calcium levels in the body may
induce several diseases:
 Rickets disease
 Adult osteomalacia
 Osteoporosis

32.  Rickets :
is a softening of bones in children potentially leading
to fractures and deformity. The predominant cause is
a vitamin D deficiency, lack calcium in the diet may
also leads to rickets
 Osteomalacia :
is the softening of the bones due to
defective bone mineralization It may
show signs as diffuse body pains, fragility
of the bones. A common cause of the disease is
deficiency in vitamin D, which is normally obtained
from the diet and/or sunlight exposure

34. Calcium metabolism disorder include:
 Hypercalcemia
 Hypocalcemia
 hyperparathyrodism

35.  Is condition in which the calcium level in the body is above the normal.
 The need of the calcium for the bone formation and muscle contraction,
releasing hormone .
 The main cause is over activity of the parathyroid gland.
 Cancer and some medication may cause over activity of the calcium level.
Etiology :-
 Increased GI Absorption:
Vitamin D excess
Elevated PTH
 Decreased Urinary Excretion:
Thiazide diuretics
 Increased Loss From Bone:
Elevated PTH
Hyperparathyroidism
Malignancy
Osteolytic metastases

36.  Metastatic calcification
 Renal stones

37.  Is a condition in which the calcium level below the normal level
 Is caused by low level of PTH , low level of magnesium, deficiency of
vitamin D
 The kidney dysfunction play role in hypocalcaemia .
Etiology :-
 Decreased GI Absorption
 Poor dietary intake of calcium,impair absorption
 Increased Urinary Excretion
 Decreased Bone Resorption/Increased Mineralization
 Low PTH
 PTH resistance
 Vitamin D deficiency

38.  Tetany: condition of mineral imbalance in the
body that results in severe muscle spasms.
usually occurs when the concentration of
calcium ions (Ca++) in extracellular fluids
below normal

39.  Hyperparathyroidism occur in two major forms:
 Primary: most common cause of hypercalceimia.it
represents autonomous production of PTH.
 Secondary:is caused by any chroinc condition
assocaited with chroinc depression in the calcuim
level.
 Tertiary hyperparathyroidism: rarely occur

40.  Overall, we need good sources of calcium in our
diets, good nutritional habits, and a diet that
promotes healthy gastrointestinal function.
Taking calcium and magnesium at bedtime or
between meals, when the stomach may be more
acidic, is often helpful for better absorption.
Regular exercise, good nutrition, and lots of
vegetables are important basics for providing the
essential calcium we need and good health in
general