2. 2
Index
1- Introduction. 2-3
2- Major minerals. 5-10
Calcium 4–8
Other elements P,Na,Cl,K,S,Mg 8-10
3- Minor minerals(Trace minerals). 11-16
Iron 12-14
Other elementsZn,I,Co,Se,Cu,F,Cr 15-17
4- References 17
3. 3
Minerals
Functions of minerals
-Building tissue
- Activating, regulating, transmitting, and controlling metabolic processes
Major elements : Requirement >100 mg /day
-These minerals are called macrominerals.
Bone,muscle,heart and brain function depends on these minerals.
Calcium – Chloride – Magnesium - Sulphur- Phosphorous- Fluoride- Sodium - Potassium.
Trace elements : Requirement<100mg/day microminerals.
The body needs small quantities of: Iron - Chromium - Copper - Fluoride - Iodine
–- Manganese -
Molybdenum -
Selenium- Zinc.
Necessary for the body
but their exact
functions are not
known. Ex.: Iron ,
Chromium.
Non-Essentials : seen in
tissues. Contaminants
in food stuffs. Ex.:
Rubedium, Silver,
Gold,Bismuth
Toxic : should be avoided.Ex.: Aluminium, Lead, Cadmium, Mercury
Except for chromium, all trace minerals are incorporated into enzymes or
hormones required in body processes(metabolism).Chromium helps the body
keep blood sugar levels normal.
4. 4
Mineral metabolism
Digestion: minerals do not require much digestion.
Absorption:rate determined by food form, body need, tissue health.
Transport: enter through portal circulation, bound toproteins.
Tissue uptake: controlled by hormones, excess excreted in urine.
Occurrence in the body: basic forms are free ions and covalently bound.
- Homeostatic mechanisms regulate the concentration of minerals in body fluids.
- Mineral toxicity can result from too much of a mineral or from overexposure to
industrial pollutants, household chemicals, or certain drugs
- The body varies in it’s capacity to absorb and use the minerals in food. Here are
some things that affect the bioavailability of minerals in food:
Type of Food
o The small intestine readily absorbs minerals in animal products
because plant binders and dietary fibers are unavailable to hinder
digestion and absorption.
o Foods from the animal kingdom generally contain high mineral
concentration (except for magnesium, which has higher
concentration in plants.)
Mineral-Mineral Interaction
o Many minerals have the same molecular weight and have to
compete with each other for intestinal absorption.
Vitamin-Mineral Interaction
o Vitamin D helps with calcium absorption
o Vitamin C helps with iron absorption
Fiber-Mineral Interaction
o High fiber intake blunts the absorption of some minerals like calcium,
iron, magnesium, and phosphorus by binding them and causing them
to pass un absorbed.
Consuming too little or too much of certain minerals can cause a nutritional disorder.
However, people who follow restrictive diets may not consume enough of a particular
mineral (or vitamin). For example, vegetarians, including those who eat eggs and dairy
products, are at risk of iron deficiency. Infants are more likely to develop deficiencies
because they are growing rapidly (thus requiring larger amounts of nutrients for their size
than adults).
5. 5
Minerals serve 3 main purposes in the body:
Structure forming bones and teeth.
Function maintain normal heart rhythm, muscle contraction, neural conductivity, and acid-
base balance.
Metabolism Regulation they become part of enzymes and hormones that control cell
activity and the buildup (anabolism) and breakdown (catabolism) of the macronutrients.
Major minerals sources & main functions and RDA
6. 6
Calcium (Ca)
Most abundant mineral in the human body .
Total Calcium in the human body is about 1 to 1.5 kg, 99% of which is seen in bone together
with phosphate.Small amounts in soft tissue & 1% in extracellular fluid
Dietary Sources of calcium: Milk is a good source for calcium,Egg, fish, cheese, beans,
lentils, nuts, cabbage and vegetables.
Daily requirement
Adults : 500 mg/day
Childrens:1200mg/day
Pregnancy &lactation : 1500 mg/day
After the age of 50, tendency for osteoporosis, prevented by increased calcium (1500
mg/day) & vitamin D (20 μg/day) Body
Calcium in plasma is of 3 types : Ionized or free or unboundcalcium.
In blood, 50% of plasma calcium is free & is metabolicallyactive.
It is required for the maintenance of nerve function, membrane permeability, musclecontraction
and hormone secretion.
Bound calcium:
40% of plasma calcium is bound to protein mostlyalbumin.
(These two forms are diffusible from blood totissues.)
Complexed calcium:
10% of plasma calcium is complexed with anions including bicarbonate, phosphate, lactate &
citrate..
Normal Range: The normal level of plasma calcium is 9 - 11 mg/dl .
Absorption taken in the diet as calcium phosphate, carbonate & tartaratesalt.
In gut and first & second part of duodenumagainst a concentration gradient & requires energy.
Requires a carrier protein, helped by calcium-dependentATPase.
Two mechanisms Simple diffusion + active transport [Process involving energy & Ca2+ pump]
require Calcitriol carrier(vit.D derivative activeted by kidney) --> synthesis of Ca-binding proteins
& transport.
Excretion stool & urine
7. 7
Biochemical functions
1-Bones &Teeth:Formation of bone &teeth.Bones are reservoir for Ca in the
body.Osteoblasts → bone deposition , Osteoclasts → demineralization.
2- Nerve conduction: stimulates
exocytosis of synaptic vesicles
containing ACh ACh release into
synaptic cleft.
3-Muscle Contraction:Ca mediates
excitation & contraction.
- Ca interacts with Troponin-C to
trigger muscle contraction. - Ca activates ATPase, ↑ interaction between actin
and myosin facilitates excitation-contraction coupling.
-Action on Heart: Ca
prolongs Systole. ↑ Ca
concentration → ↑
myocardial contractility.
4-Blood coagulation:
Calcium is known as factor IV
in blood coagulation
process. Prothrombin contains γ-carboxyglutamate residues which are chelated
by Ca2+ during the thrombin formation
5- Secretion of hormones : insulin, parathyroid hormone, calcitonin,
vasopressin.
6-Second Messenger:Ca& cyclic AMP are 2nd messengers of different
hormones. Eg: Glucogan.
7- Activation of Enzymes:Calmodulin – Ca binding regulatory protein. Binds with
4 Ca ions and leads to activation of enzymes.ex pancreatic lipase, enzymes of
coagulation pathway, and rennin.
8 -Membrane integrity &Permeability:Influences transport of number of
substances across the membranous barrier.
8. 8
Factors causing increased absorption:.
1-Vitamin D: Calcitriol induces the synthesis of carrier protein
(Calbindin)facilitates the absorption.
2-Parathyroid hormone: ↑ transport from the intestinal cells by
enhancing 1α- hydroxylase activity.
The enzyme catalyzes the hydroxylation of Calcifediol to calcitriol
(the bioactiveform of Vitamin D) Cacarrier.
3-Acidity: Ca-salts, particularly PO4 & carbonates are quite soluble in
acidicsolutions.In alkaline medium, the absorption of calcium is lowered due to the
formation of insoluble tricalcium PO4
4-Amino acids: Lysine & arginine Amino acids ↑ the solubility ofCa-salts.
5-Sugars and organic acids: Organic acids produced by microbial fermentation
of sugars in the gut ↑the solubility of Ca-salts.
Factors causing decreased absorption
1-Phytic acid( in Cereals) and oxalates(in some leafy vegetables)
forms insoluble Ca-salts.
2-Fibres: Excess of fibres in the diet interferes with the absorption.
3-High dietary phosphates - precipitate as calciumphosphate.
4-High pH - (alkaline)
In alkaline medium, the absorption of calcium is lowered due to
the formation of insoluble tricalcium PO4
5-Malabsorption syndromes: formation of insoluble Ca salt of fatty acid.
6-Glucocorticoids: Diminishes intestinal transport of calcium Phosphate:
7-High phosphate content will cause precipitation as calcium phosphate
Magnesium: High content of Mg
decreases the absorption.
Homeostasis of Ca
The major factors regulate the plasma
Calcium:
Calcitriol↑ intestinal absorption of
Ca↑ Ca uptake by osteoblasts↑
promotes Calcification.
Parathyroid hormone
↑serum Ca Demineralization of
bone(Osteoclasts)↑ Ca reabsorption by
renal tubules↑ intestinal absorption of
Ca
by promoting synthesis of Calcitriol .
Calcitonin
secreted by Para follicular cells of Thyroid gland Lowers the serumCa
Calcification of bone(by osteoblasts)↑the excretion of Ca into urine.
9. 9
Phosphorous (P)
Sources red meat, fish, poultry, eggs, whole grains, nuts and seeds.
Biological function:
An essential component of bone, cartilage and the crustacean exoskeleton.
Phosphorus is an essential component of phospholipids, nucleic acids, phosphoproteins
(casein), high energy phosphate esters (ATP), hexose phosphates, creatine phosphate,
and several key enzymes.
As a component of these important biological substances, phosphorus plays a central
role in energy and cell metabolism.
Inorganic phosphates serve as important buffers to regulate the normal acidbase
balance (ie. pH).
How Phosphorous Works in the Body
Phosphorus works with calcium to help build bones. the most important thing is balance.
With too much calcium, your body absorbs less phosphorus, and vice versa. Like calcium,
you need vitamin D to absorb phosphorus properly.
Magnesium (Mg)
Sources distributed in vegetables & also found in almost all animal tissues Other
important sources are cereals, beans, green vegetables, potatoes, almonds, and dairy
products, e.g. cheese.
Biochemical functions
1-Co-factor: in peptidases, ribonucleases, glycolytic enzymes & co-carboxylationreactions.
2-It nfluences the secretion of PTH by the parathyroid glands &hypomagnesaemia
may cause hypoparathyriodism.
3-Magnesium exerts an effect on neuromuscular irritability similar to that of Ca2+,
high levels depress nerve conduction & low levels may produce tetany
(Hypomagnasemictetany).
4-About 70% of body magnesium is present as apatites in bones, dental enamel and
dentin.
5-Insulin-dependent uptake of glucose is reduced in Mg2+
deficiency,magnesium supplementation improves glucose tolerance.
6-Required for DNA replication process (DNA Polymerase III).
Sulphur )S)
Biological function:
component of several key amino acids (methionine and cystine), vitamins (thiamine and
biotin), the hormone insulin, and the crustacean exoskeleton.
As the sulphate, sulphur is an essential component of heparin, chondroitin, fibrinogen and
taurine.
Several key enzyme systems such as coenzyme A and glutathione depend for their activity
on free sulphydryl (SH) groups.
Dietary sources sulphur containing amino acids include fish meal, chicken eggs.
10. 10
Sodium, Potassium and Chlorineoccur almost entirely in the fluids and soft
tissues of the body, (Na) and (Cl) mainly in the body fluids, and (K) mainly in the
cells. They serve a vital function in controlling osmotic pressures and acid-base
equilibrium. They also play important roles in water metabolism.
Sodium (Na)
Sources Common salt - Bread -whole grains-Nuts-leafy vegetables-Eggs -Milk
Functions
1-AS sodium bicarbonate regulates the body acid base balance.
2-Sodium regulates ECF volume: Sodium pump is operating in
all cells, so as to keep Sodium extracellular.
3-This mechanism is ATP dependent.
4-Required for maintenance of osmotic pressure and fluid
balance.
5-Necessary for normal muscle irritability and cell permeability.
Chloride (Cl)
Sources: Table salt, leafy vegetables, eggs, milk.
-Except for the hydrochloric acid of the gastric juice, practically all the chlorine involved in
metabolism enters, exists in, and leaves the body in the form of chlorides, much the greater
part as Sodium chloride.
Functions
1-As a part of sodium chloride, chloride is essential for water balance, regulation of osmotic
pressure and acid-base balance.
2-Chloride is necessary for the formation of HCL by the gastric mucosa and for the
activation of enzyme amylase.
3-It is involved in the chloride shift.
4- Resulting from processes of building (anabolism) and breaking down (catabolism) body
tissues.Chlorine also plays a specific role in the transport of oxygen and carbon dioxide in the blood.
Potassium(K)
Sourcecitrus fruits, vegetables, grains, salmon, chicken, whole milk and almonds. important
sources (avocados, bananas and coconut water).
Functions
1-Stroke: it allows more O2 to reach the brain by stimulating neural activity and increasing
cognitive function.Since act as a vasodilator, the blood vessels relax throughout the body
when proper amounts of potassium are consumed. This means that blood flows more
freely, and is less likely to clot and break off to cause Strocks.
2-Muscle disorders: required for contraction and relaxation of musclesregular.
3-Blood Pressure: reversing the role of sodium in unbalancing normal blood pressure.
(maintains the normality of blood pressure in the human body).
4-Water BalanceIt rehydrates and optimizes fluid balance.
5-Electrolytes: electrolytes help to transmit electrical charges throughout the body from the
brain and nervous system, so extra electrolytes keep everything functioning faster and
more efficiently in the body.
12. 12
Iron (Fe)
Sources spinach, turnip, sprouts, broccoli and dry fruits also have good iron content.meat
Importance:
1-Tissue Respiration:-Iron can change readily between Ferrous and Ferric states and
function in electron transfer reactions.(Cytochromes - NADH dehydrogenase -Succinate
dehydrogenase)
2-Transport of gases :Able to bind with molecular O2 and CO2.
The main function is to coordinate the O2 molecule into heme of hemoglobin, so that it can
be transported from the lungs to the tissues.
3-Oxidative Reactions : Component of various oxidoreductase enzymes
4- Immune Response :Required for effective activity of lysosomal enzyme peroxidase –
helps in phagocytic and bactericidal activity of neutrophils.
Total body iron content : 3 - 5 gm
Heme containing proteins: Hb, myoglobin, cytochromes, cytochrome oxidase, catalase,
peroxidase, xanthine oxidase & Trp pyrrolase.
Non-heme iron containing proteins : ferritin, transferrin, hemosiderin, lactoferin (milk) &
neutrophils.
Factors affect on absorption:
-Ferric ions are reduced with the help of gastric HCl, ascorbic acid, cys. and -SH groups of
pro. favors absorption.
- Ca, Cu, Zn, Pb inhibit absorption. ↓
- Phytates (in cereals), oxalates (leafy veg) & phosphates in the diet reduce↓absorption by
forming insoluble iron salts.
- Marginal ↓ by tea & eggs.
13. 13
Metabolism of Iron
1-Inorganic/non-heme iron (90%) Fe3+ (less soluble) - Organic/heme iron (10%) Fe2+ (more
soluble) To be soluble, Ferric (Fe3+) needs to be reduced toFerrous (Fe2+) by enzyme
Duodenal cytochrome b
(Dcytb)( Vitamin Cdependent).
2-From the gut lume moved
into the enterocyte before
getting to the bloodstream by
transporter.Inorganic iron
uses DMT1& Organic iron uses
HCP1.(ferrous binds to mucosal cell protein called Divalent Metal Transporter-1 (DMT-1)
and transported into the mucosal
cell.[Unabsorbed Iron is excreted.]
3-Iron oxidized to ferric state.complexed
with apoferritin to form Ferritin.
4-Ferric Iron is released, reduced to
Ferrous state crosses the cell membrane.
Reoxidized to Ferric state by
Ceruloplasmin
5-Ferric Iron bound with Transferrin and
transported to tissues.Iron is stored in
liver, spleen & bone marrow in the form
of ferritin(temporary
storage).Hemosiderin It is another iron
storage protein, which accumulates when iron levels are increased.
In the liver, iron is stored as ferric ion into ferritin, and is released by ferroportin and
ceruloplasmin bound to Tf, as needed.
In the bone marrow, iron is used by erythroid precursors to synthesize hemoglobin.
Iron is recycled by macrophages, especially in the spleen.
In macrophages, Macrophages engulfs old RBCs and releases heme.
Heme contains protoporphyrin and Fe.
Heme oxygenase separates them and Fe is then stored as ferritin.
iron may accumulate as hemosiderin or released back into the circulation by ferroportin
and ceruloplasmin.
Hepcidin (binds to ferroportin–Fe exporter-), a hormone synthesized by the liver, acts as
the main negative regulator of iron absorption in the duodenum and of iron release by
macrophages.
Iron is lost in very small quantities in feces, but menstruation, pregnancy, and lactation
may cause important iron loss in women.
1-Fe2+ is transported out by ferroportin1(FPN)Once it leaves the enterocyte, the Fe2+
changes back to Fe3+ by Hephaestin.
Once in the bloodstream, Fe3+ couples with Transferrin (Tf) forming a Tf-Fe complex.
2-Tf-Fe complex meets up with transferrin receptor 1 (TfR1) in most cells.
Proton ATPase drops the pH in the endosome to release Fe3+ from Tf.
15. 15
Zinc (Zn)
Sources: meat and other proteins
stuff.
Active transport of zinc into portal
bloodis mediated by
metallothionein.Zinc competes
with other metals for absorption,
and absorption is believed greatly
retarded by ingestion of fiberand
phytates.
Functions
1- It plays a role in cell division, cell growth, wound healing, and the breakdown of
carbohydrates.
2- Zinc is also needed for the senses of smell and taste.
3- During pregnancy, infancy, and childhood the body needs zinc to grow and develop
properly.
Iodine (I)
Sources
large quantities in marine plants and animals.Garlic, lima beans, summer squash, sesame
seeds. Iodized salt.
Functions
1- Metabolic Rate: Iodine influences the functioning of thyroid glands by assisting in the
production of hormones, which are directly responsible for controlling the body’s
base metabolic rate.
2- Energy Levels:by ensuring the efficient utilization of calories, without allowing them
to be deposited as excess fats.
3- Formation of healthy and shiny skin, teeth and hair.
4- immune System Strength: Iodine is itself a scavenger of free hydroxyl radicals(like
vitamin-C),it also stimulates antioxidants throughout the body to provide a strong .
5- Reduce conditions like fibrosis, turgidity, and breast tenderness.
Cobalt(Co)
Biological function: The principal biological functions of cobalt may be summarised as
follows;
Cobalt is an integral component of cyanocobalamin (vitamin B12), and as such is essential
for red blood cell formation and the maintenance of nerve tissue.Although not confirmed,
cobalt may also function as an activating agent for various enzyme systems.
Dietary sources and absorption: Rich dietary sources of cobalt include copra meal (2 mg/kg
Co), linseed meal, dried brewers yeast, fish meal, meat meal, cottonseed meal, and
soybean meal (0.5–0.1 mg/kg).
16. 16
Selenium (Se)
Sources Plants (varies with soil content) , meat , sea foods.
Biochemical Functions
-Selenium, as selenocysteine is an
essential component of the enzyme
glutathione peroxidase.
-Glutathione peroxidase functions as
an antioxidant enzyme. It suppresses
the oxidative stress by converting
oxygen free radicals into less toxic
forms or non-toxic forms.
1- Acts as a non-specific intracellular
antioxidant , it protects the cells against the damage caused by H2O2 .
2- Complementary to vit.E : availability of vit.E reduces the Se requirement.
4- Protects from developing liver cirrhosis.
5 - Selenium contains enzyme 5’deiodinase converts thyroxine (T4) to triiodo-thyronine (T3)
in thyroid gland.
6- Selenium may exert anticancer effects because of its antioxidant role.
Copper (Cu)
Sources:lgumes, nuts, seeds, whole grains and drinking water
Health benefits of Copper:
Proper Growth-Pigmentation of Hair and Eyes-Brain Stimulation
Utilization of Iron and Sugar.
Copper is part of many enzymes needed for iron metabolism
Enzymatic Reactions: Copper is either an element or a cofactor in as many as 50 different
enzymes
THE ESSENTIAL ROLE OF COPPER-TRANSPORTING ATPases ATP7A AND ATP7B IN HUMAN
PHYSIOLOGY. This process is essential for human growth and development.
Fluoride(F)
Main Functions:
Involved in formation of bones and
teeth; helps prevent tooth decay
Source:Drinking water (either fluoridated or
naturally containing fluoride), fish, and most
teas
Chromium(Cr)
Biological function: Trivalent chromium is an integral component of the glucose tolerance factor (GTF;
a low molecular weight compound with trivalent chromium coordinated to two nicotinic acid
molecules with the remaining coordinates protected by amino acids) and acts as a cofactor for the
hormone insulin.
Apart from its vital role in carbohydrate metabolism (ie. glucose tolerance and glycogen synthesis),
trivalent chromium is also believed to play an important role in cholesterol and amino acid
metabolism.
Dietary sources :chick shell meal, shrimp tail meat, Artemia salina, dried brewers yeast, shellfish.
17. 17
4- References
[1] Wang J & Pantopoulos K. (2011). Regulation of Cellular Iron Metabolism. Biochem J. 434(Pt 3): 365–
381.
[2] Peeling P, Dawson B, Goodman C, Landers G, Wiegerinck ET, Swinkels DW & Trinder D. Effects of
Exercise on Hepcidin Response and Iron Metabolism during Recovery. Int J Sport Nutr Exerc Metab. 19 (6):
583-597.
[3] Díaz V. (2011). Regulation of Iron Metabolism and Exercise. Medicina Sportiva, Vol. 15 Issue 4, p 230.
[4] Mustafa A & Cagri C. (2013). Iron Metabolism and Importance of Iron in Exercise. International Journal
of Academic Research, Vol. 5 Issue 4, p 222.
[5] Qian ZM. (2002). Nitric Oxide and Changes of Iron Metabolism in Exercise. Biol Rev Camb Philos Soc.
77 (4): 529-536
[6] http://www.cell.com/action/showImagesData?pii=S1043-2760%2812%2900064-1
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