nutrient requirement for human growth-304

8/10/2019 Nutrient Requirement for Human Growth-304

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Nutrient Requirement for HumanGrowth And Development

Booklet No. 304Food and Nutrition FN!"#

$ontent%PrefaceI. Introductionll. Carbohydrates,

A Types of carbohydratesB. Functions of carbohydratesC. Sources of carbohydrates

III. ProteinsA. Types of proteinsB. Functions of proteinsC. Sources of proteins

IV. Lipids (Fats

A. Types of lipidsB. Functions of lipidsC. Sources of lipids

V. Vita!insA. Fat"soluble #ita!insB. $ater"soluble #ita!ins

VI. $aterA. Functions of %aterB. Sources of %ater

VII. &ineral 'le!ents

&refa'e

Food is rearded as the pri!e necessity of life. The food that %e consu!e in our dailydiet is diested and assi!ilated in the body and is used for its !aintenance and ro%th.)utrients are the constituents in food that are re*uired for ro%th and de#elop!ent of thehu!an body. 'ach nutrient has a specific role to play for the proper functionin of the body. Thisboo+let pro#ides #aluable infor!ation reardin the nutrients for hu!an ro%th, theirphysioloical functions and food sources.

Dr. ( ). $hand*+ A,ri'ultural - nvironmental du'ation

/. /ntrodu'tion

)utrition is the science of foods, the nutrients and other substances, their action,interaction and balance in relation" ship to health and disease condition. )utrients are theconstituents in the food that !ust be supplied to the body in suitable a!ounts. For !aintaininood health and physical efficiency, the diet should pro#ide ade*uate a!ounts of all nutrients.Therefore, it is i!portant to deter!ine physioloical re*uire!ents of #arious nutrients bydifferent ae and se roups. The infor!ation on physioloical re*uire!ents of nutrients !ustbe translated in ter!s of food consu!ed in habitual diets.

The nutrients re*uired for hu!an ro%th and de#elop!ent are-


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Carbohydrates / Proteins 0 Fats 1 Vita!ins 2 &inerals and 3 $ater.

These are eplained in detail, their functions in the body, sources, *uantity re*uire!entsfor #arious classes of people, ae, se, %or+ and special physical re*uire!ents.

//. $aroh*drate%

Carbohydrates are +no%n as 4enery yieldin substances4. &ainly the carbohydratesare, co!posed of starch, lucose, cane suar, !il+, suar, etc. It has been found out that, thecarbohydrates the cheapest source of enery supply about 15 to 627 of the total calories in thehu!an diet.

Table - Percent calories supplied by carbohydrates in a#erae diets in India

Sl.)o. 8iet 7 Calories supplied bycarbohydrates

$ell to do class 15"22

/ &iddle inco!e roups 32"92

0 Lo% inco!e roups 9:"62Children 25"32Infants 02"12

It has been suested that of the total daily enery re*uire!ents, a !ini!u! of at least157 should be pro#ided in the for! of carbohydrates. ;ence, it is i!portant to ha#e at least aeneral idea of the type of carbohydrates that occur in the hu!an diet.

A. )*pe% of 'aroh*drate%Carbohydrates are broadly classified as !ono"saccharides, disaccharides and

polysaccharides.

#. 1ono%a''haride%&onosaccharides (Si!ple suars are the si!plest of the carbohydrates. They are

na!ed accordin to the nu!ber of carbon "ato!s in the chain li+e trioses, tetroses, pentoses,heoses and heptoses. They !ay contain 0 "9 carbon ato!s. They are the co!ponents that cannot be bro+en do%n to s!allest units


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Bein a *uic+ enery releasin suar, it is used and i#en directly blood to the patients to reaintheir enery in case of e!erency.

ii. Fru'to%eFructose, +no%n as fruit suar, is !uch s%eeter than cane suar and is a product of the

hydrolysis of sucrose. Both lucose and fructose occur in free for! in a fe% foods-

iii. Gala'to%e>nly source of alactose is fro! the hydrolysis of lactose. Both fructose and alactose

are con#erted to the storae carbohydrates lycoen in the li#er and thus i#e rise to lucoseand contribute to the cell enery supply.

iv. 1anno%e&annose has only li!ited distribution in foods, is poorly absorbed, and is of little

i!portance in nutrition.

;eoses play funda!ental role in cellular nutrition and are the constituents of a larenu!ber of co!ple substances synthesi?ed by the cell such as structural co!ponents and

secretions.

. &ento%e%Pentoses ha#e fi#e carbon ato!s in the structure. @ibose, ylose and Arabinose are the

three pentoses that are of little dietary sinificance. It is rapidly synthesi?ed by the body cellthouh not a dietary essential. Pentoses also play a funda!ental role in cellular nutrition.

. Di%a''haride%8isaccharides (8ouble suars are for!ed %hen t%o heoses are co!bined toether

%ith the loss of one !olecule of %ater. >n hydrolysis they split into !ono"saccharide units.Sucrose, !altose and lactose are the three i!portant disaccharides contained in our food.

a. !u'ro%eSucrose, also +no%n as table suar is the %hite or bro%n suar %e use in our daily diet.

This is produced fro! suar, cane and suar beets. &any fruits and #eetables also contains!all a!ounts of sucrose. Althouh che!ically cane and beet suar are the sa!e, cane suarcan be crystalli?ed %hile beet suar is not. 8urin diestion sucrose is hydroly?ed to lucoseand fructose.

. 1alto%e&altose also called !alt"suar, found in sproutin rains, !alted cereals and !alted

!il+. A!on the s%eetenin aents this is found in corn syrup and co!"suar. $henhydrolysed, !altose yields t%o !olecules of lucose. &altose is of little dietary sinificance. It isso!eti!es used as dietary suar in infant feedin for!ulas.

'. a'to%eLactose, also called !il+ suar, is produced by !a!!als and is the only dietary

carbohydrate of ani!al oriin. It is about one sith as s%eet as sucrose. ;u!an !il+ contains3.67 of lactose %hereas co%s !il+ contains 1.:7. $hen lactose is hydrolysed, alactose andlucose are for!ed.

3. &ol*%a''haride%


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Polysaccharides are the co!ple carbohydrates. They !ay contain as !any as /555!onosaccharide units. $hen the polysaccharide contain only one !onosaccharide, then it issaid to be ;o!o"polysaccharide %hen the polysaccharide contain se#eral different!onosaccharides or its deri#ati#es, it is said to be ;etero"polysaccharide. Polysaccharides%hich are i!portant in nutrition are starch, detrin, lycoen and cellulose. There are threetypes of polysaccharides- (a Indiestible, (b Partially diestible and (c 8iestible.

a. /ndi,e%tileIndiestible polysaccharides are those %hich can not be diested by the diesti#e tract

of the hu!an body. These only pro#ide the bul+ to the diet and help in peristaltic !o#e!ent inthe intestines. These include cellulose, he!i"cellulose, pectins, and u!s. A!on thesecellulose play an i!portant role. Cellulose is the structural co!ponent of the plant cell. In hu!anfood, cellulose referred to as fibre, pro#ides a source of rouhae in the intestinal tract %hichaids nor!al peristaltic action of the intestine, absorbs !oisture and pro#ides bul+ to sti!ulatenor!al e#acuation of the lare intestine.

. &artiall* di,e%tilePartially diestible polysaccharides are those %hich are diested by the hu!an body

only to so!e etent. These includes, Inulin, =alactoens, &annosans, @affinose andPentosans.

'. Di,e%tile8iestible polysaccharides are those %hich can be diested co!pletely by the diesti#e

syste! of the hu!an body. These include (i starch (ii 8etrins and (iii =lycoen.

i. !tar'hStarch is the storae for! of carbohydrates in plant and pro#ides a #aluable contribution

to the enery content of the diet. Coo+ed starch is !ore palatable and easily diested. The endproduct of all starch %hen it is hydroly?ed is lucose.

ii. De2trin%8etrins are the inter!ediate products in the hydrolysis of starch. They are abundant in

er!inatin seeds. So!e detrins are produced %hen flour is bro%ned or bread is toasted.Since, detrins are produced as inter!ediate products in the hydrolysis of starch they are nottoo i!portant as a source of carbohydrates.

iii. Gl*'o,en=lycoen is also called as ani!al starch is the storae for! of starch polysaccharides in

the body. It is found in the li#er of all ani!als and in s!all a*uatic ani!als. It is rapidlysynthesi?ed fro! lucose in the li#er and !uscle. =lycoen is found in the body as reser#e asthe body cannot store lycoen in the sa!e %ay as it stores fat. Li#er lycoen is a#ailable as asource of enery to all body cells. In s+eletal !uscle, lycoen ser#es as a source of enery for

!uscle contraction.

B. Fun'tion% of 'aroh*drate%Carbohydrates pro#ide a #ariety of functions. The !ost. i!portant of these is to supply

enery for the body processes. The inta+e of carbohydrate is reater than fat in a#erae Indiandiets. The i!portant functions of carbohydrates are i#en here.

#. !our'e of ener,*


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'ach ra! of carbohydrate %hen oidi?ed pro#ides approi!ately 1 +cal of enery%hich %ill be utili?ed for all the bodily functions. =lucose solutions are used for i!!ediate tissueenery needs. S!all a!ounts are stored as adipose tissue for later enery needs. =lucose isthe sole for! of enery for the brain in and ner#ous tissue. Carbohydrates are con#erted to fatas a larer reser#e for enery. The total lycoen reser#es in the body %ould !eet about half ofone days enery needs of the adult.

. &rotein %parin, a'tionSince, carbohydrates is used as a source of enery, it is to be ade*uately supplied in the

diet. Any deficiency of the carbohydrates in the diet is !ade up by usin fats of adipose tissueand protein tissues. This further results in protein deficiency in the hu!an bein. Protein"enery!alnutrition (P'& disorders are caused, by such protein"carbohydrate deficiency. This leads tothe diseases in youn children #i?. %ashior+ar and &aras!us. ;ence, ade*uate supply ofcarbohydrate to spare protein for its pri!ary purpose of body buildin and repair of tissues is#ery i!portant.

3. Re,ulation of fat metaoli%mCertain a!ount of carbohydrate is necessary in the diet so that the oidation of fats can

proceed nor!ally. In the absence of ade*uate carbohydrates lare a!ounts of +etone bodiesare produced. The accu!ulation of +etone bodies increases the acidity of blood. This conditionis called 4etosis4. etosis is a condition %hich !ay occur in diabetes %here the cells cannotutili?e carbohydrates. It !ay also occur in star#ation %here the cells !ust use fat sources of thebody for enery.

4. !upport ,a%tro"inte%tinal fun'tionThe carbohydrates ser#e as a source of enery for the !icro oranis!s that synthesi?e

so!e B"co!ple #ita!ins in the intestinal tract and the cellulose pro#ides fibre and bul+ thatpro!ote healthy intestinal hyiene.

5. Add variet* to the food

Carbohydrate foods also add #ariety, fla#our and bul+ to the diet.

6. 1ain 'on%tituent in the od*Carbohydrates for! a !aDor portion in the hu!an body is 055 "025 !. >f this, 55 !

is stored as lycoen in cardiac, s!ooth and s+eletal !uscles, and about ! !a+e up thelucose in the blood and etra"cellular fluid. Carbohydrates pro#ide the carbon, %hich help inthe synthesis of the non"essential a!ino"acids by the body.

7. Dietar* fire8ietary fibre yields no nutrients to the bodyE but aids in the sti!ulation of peristaltic

!o#e!ents of the astro"intestinal tract, i#e bul+ to the intestinal contents, and reduces thelenth of ti!e that food %astes re!ain in the colon.

8. Help in a%orption of 'al'ium and pho%phoru%Lactose underoes fer!entation by lactic acid bacteria in the intestinal tract and this

helps in the absorption of calciu! and phosphorus.

$. !our'e% of 'aroh*drate%The richest sources of carbohydrates in food are suars, cereal rains, leu!es and

dried fruits. Fat, !il+ products, Da!s, Dellies, pastries, breads, ca+es and candies ha#eappreciable *uantities of carbohydrates. Bananas, dates, potatoes and s%eet. potatoes are also


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rich in carbohydrates. Foods of ani!al oriin such as es, fish, poultry, cheese, fresh !il+, and!eats (ecept li#er contain #ery little carbohydrates, ani!al and #eetable fats contain nocarbohydrates at all.

///. &rotein%

Proteins are the i!portant substances in the cells of the body. They for! the i!portantconstituents of !uscles and other tissues and also of the #ital fluids li+e blood. Proteins pro#idethe buildin !aterials for the body and !aintain the %ear and tear of tissues, %hich is a nor!aland a constant feature of the life process, therefore, the foods rich in proteins are called the4body buildin foods4. ;ence, proteins are of the !ost i!portant nutrients. Proteins are alsooidi?ed in the body to pro#ide enery. In s!all intestine, proteins of food are bro+en do%n tosi!pler substances called a!ino"acids that are absorbed in blood, and ta+en to different parts,and specific proteins are aain for!ed.

A. )*pe% of protein%Proteins are classified on the basis of their physical and che!ical properties, their a!ino

acid structure or accordin to their nutritional properties.

#. &h*%i'al and 'hemi'al propertie%Based on the physical and che!ical properties proteins are classified into si!ple,

conDuated and deri#ed proteins.

a. !imple protein%Si!ple proteins %hen hydrolysed by acids, al+alies, or en?y!es, yield only a!ino"acids.

These include albu!ins, lobulins found %ithin all body cells and in blood seru!, +eratin,collaen and elastin in supporti#e tissues of the body and in hair and nails, lobin in he!olobinand !yolobin, ?in in corn, liadin and lutelin in %heat, leu!in in peas, and lactalbu!in andlacto"lobulin in !il+.

. $on9u,ated protein%ConDuated proteins are the si!ple proteins co!bined %ith a non"protein substance.

;ence, they are called conDuated. These include the follo%in.

i. ipo"protein% "they ser#e as #ehicles for the transport of fats in the blood.ii. Nu'leo"prot'in%" they are the proteins such of the cell nuclei, #irus, etc.iii. &ho%pho"protein%" they are the proteins such as casein in !il+ and o#o"#itellin in es.iv. 1etallo"protein%" they are the proteins such as en?y!es that contain !ineral ele!ents.v. 1u'oprotein% "they are the proteins found in connecti#e tissues, !ucin, and onadotropichor!ones.vi. $hromo"protein%" they are the proteins such as hae!olobin and #isual purple, andvii. Flavo" protein%" they are the en?y!es that contain the #ita!in ribofla#ien.

'. Derived protein%8eri#ed proteins are those proteins that are deri#ed as a result fro! the action of

en?y!es on si!ple and conDuated proteins. They include the substances li+e peptones peptideand proteoses.

. Amino a'id 'ontent of proteinThere are t%enty "one a!ino" acids co!!only tound in dietary proteins. They are-

Alanine, Arinine, Cystine, Aspartic acid, Cysteine, =luta!ic acid, )orleucine, =lycine,


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;istidine, Isoleucine, Leucine, Lysine, &ethionine, Phenylalanine, Proline, Serine, Threonine,Tryptophan, Tyrosine, Valine and hydroy proteine. The etent to %hich the a!inoacids arepresent deter!ines the *uality of the protein in any food.

a. Non"e%%ential amino a'id%The a!ino acids that can be synthesi?ed by the body itself throuh !utual inter"

con#ersions, non"protein sources are the non"essential a!inoacids. The body can synthesi?eonly so!e of these t%enty one a!ino acids. These are then, synthesi?ed fro! an a#ailablesource of nitroen and a carbon"structure.

. %%ential amino"a'id%'ssential a!ino acids are those that the body can not synthesise at a rate sufficient to

!eet body re*uire!ents and ha#e to be supplied throuh the diet. 'iht essential a!inoacidsare isoleucine, leucine, lysine, !ethionine, phenylalanine, trytophan, threonine and #aline.

Arinine and histidine are essential only for youn infants till the ability to synthesise the! in thebody.

&ied diets contain a!ple a!ount of both essential and non"essential a!ino acids.

3. Nutritional qualitie%Proteins !aintain life and pro!ote ro%th. 8ifferent proteins fulfill there functions to

different le#els, and accordin to this they are classified as co!plete, partially co!plete andtotally inco!plete proteins.

a. $omplete protein%Co!plete proteins contain enouh of the essential a!inoacids to !aintain body tissues

and to pro!ote a nor!al rate of ro%th. ', !il+ and !eat (includin poultry and fish proteinsare all co!plete but are not necessarily identical in protein *uality.

. &artiall* 'omplete protein%

Partially co!plete proteins can !aintain life but they lac+ in sufficient a!ounts of so!eof the essential a!ino" acids for ro%th. ;ence, they are na!ed as 4Partially co!pleteproteins4. Partially co!plete proteins are obtained fro! cereal and leu!es.

'. )otall* in'omplete protein%Totally inco!plete proteins are incapable of replacin or buildin ne% tissues and hence

cannot support life. ein in co! and elatin are ea!ple of this type, as they are incapable ofper!ittin life to continue.

B. Fun'tion% of protein%I!portant functions of proteins are discussed here. &aintenance and ro%th Protein is

essential for tissue synthesis as it is the chief solid !atter of all the body tissues. Proteins are

the chief constituents of the !uscles, orans, and endocrine lands. They are the !aDorconstituents of the !atri of bones and teeth, s+in, nails, hair, blood cells and seru!, ;ence, the!ost .i!portant function is to supply the !aterials for the buildin and the continuousreplace!ent of the cell protein throuhout the life processes.

. Re,ulation of od* pro'e%%e%&any body processes are reulated by certain proteins. Body proteins ha#e hihly

speciali?ed functions in the reulation of body processes. Sa!e of these include nucleo"proteins %hich help in the synthesis of body proteins. ;ea!olobin, an iron"bearin protein that


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is the chief constituent of red blood cells, perfor!s a #ital role in carryin oyen to the tissues.The bodys resistance to disease is !aintained in part by antibodies %hich are protein in nature,these are called i!!uno"proteins. So!e en?y!es and hor!ones li+e insulin and thyroid arealso protein in nature. 'n?y!es help in process li+e diestion, absorption, anabolis! andcatabolis!.

3. !our'e of ener,*Proteins are a potential source of enery. 'ach ra! of protein yield 1 calories if

oidi?ed in the body. =enerally, protein foods are epensi#e and cheaper carbohydrates shouldpreferably be used for enery. 'cess of protein is con#erted into fat and stored in the body.

4. !tora,e formProteins are stored in youn and prenant %o!en for future use %hen the de!and

increases.

5. Help in la'tation pro'e%%Proteins help in the synthesis of !il+ proteins and anti bodies in lactatin %o!en.

6. $atal*%tProteins help in the synthesis of en?y!es %hich act as catalysts to #arious che!ical

reactions in the body.

7. 1u%'le 'ontra'tionThe contractile proteins (!yosin, actin reulate !uscle contraction.

$. !our'e% of protein%Proteins are one of the !ost i!portant nutrients and the sufficiency of protein in a diet is

an i!portant !easure of the ade*uacy and *uality of the diet. Ani!al foods such as !eat, fishand es are ecellent sources of proteins. They pro#ide the protein per portion of the foodeaten. >ther ood sources of proteins are foods li+e !il+, cheese, soyabean, and sausaes.

A!on the #eetable food, pulses and nuts are the richest sources of protein %itha!ounts often eceedin those present in ani!al foods. Peanuts, reen beans, reen peas,leu!es, different types of pulses and cereals contribute an appreciable a!ount of protein.Foods li+e potatoes, #eetables, fruits and fruit Duices, fats and oils, suar and Daery,contribute a #ery !eare percentae of proteins for the daily diet.

/:. ipid% ;Fat%ther fun'tion%Vita!in A influences the synthesis of both seru! and !uscle proteins and its apparent

effect on cell differentiation !ay be related to a role in 8)A and @)A !etabolis!. 8e#elop!entof anae!ia is said to occur as a result of chronic #ita!in A deficiency. ;ence, it can besuested that #ita!in A !ay be necessary for nor!al iron !etabolis!.

. !our'e%>nly ani!al foods contain #ita!in A as such, li+e, fish li#er oils, !il+, butter, hee, curd,

cheese, e"yol+, li#er and fruit fortified !ararines. The li#er oil of certain fish li+e cod, halibutand shar+ are the richest sources of Vita!in A.

Vita!in A is not present as #ita!in A in #eetable foods but these substances containcarotenes %hich are con#erted to A in the body. Carotene is also +no%n as pro"#itan!in A.

=reen leafy #eetables- spinach, turnip tops, beet reens, a!aranth, coriander lea#es,curry lea#es, dru!stic+s. =reen ste! #eetables, asparaus, broccoli, Gello% #eetables-Carrots, s%eet potatoes, pu!p+in. Gello% fruits- &anoes, papaya, to!atoes, peaches,

In eneral, the dar+er the colour of the reen #eetables, reater is their carotenecontent.

. :itamin DVita!in 8 is a co!pound of carbon, hydroen and oyen. Pure #ita!in 8 has been

isolated and is also +no%n as the anti"rachitic #ita!in. Vita!in 8 is a roup of co!ple alcoholco!ponents but is enerally spo+en of as one substance. The t%o i!portant acti#e for!s of#ita!in 8 of nutritional sinificance are-

Vita!in 8/ +no%n as erocalciferol and #ita!in 80 +no%n as cholecalciferol. Theprecursor of #ita!in 8 in the body is a pro"#ita!in, that is, 9 "dehydrocholesterol %hich is foundin the s+in. This reacts %ith ultra"#iolet rays of the sunliht to for! chole calciferol, the acti#efor! of #ita!in 8.

a. Fun'tion%Vita!in 8 play an i!portant role in the ro%th of hu!an body and in the utili?ation of

calciu! and phosphorus.


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i. GrowthVita!in 8 is re*uired for nor!al ro%th in the hu!an body. It increases the calciu! and

phosphorus absorption fro! the astro"intestinal tract by !a+in its !e!branes !oreper!eable to these salts. It i!pro#es the calcification of bones by reulatin the a!ount ofcalciu! and phosphorus that is a#ailable.

ii. ?tili@ation of 'al'ium and pho%phoru%Cereals contain phytic acid and calciu! co!bines %ith phytic acid in the body to for!

calciu! phytate. This is an insoluble co!pound and cannot be absorbed by the body. Phytateen?y!e hydrolyses the phytic acid hence pre#entin, the for!ation of calciu! phytate. Vita!in8 increases the acti#ity of this en?y!e. Thus, it helps to !ai!i?e the utili?ation of calciu! andphosphorus.

. !our'e%Food sources rich in #ita!in 8 include li#er oil, e yol+, !il+, !il+ fat, butter and hee.

Co!!on #eetable foods do not contain #ita!in 8. 'posure to sunliht pro#ides a cheap %ayof per!ittin the production of #ita!in 8 in the body itself. 'posure to sunliht, fortified foods,

fish"li#er oils, and co!!ercial #ita!in 8 preparations are the sources of #ita!in 8.

3. :itamin Vita!in ' is a tat"soluble #ita!in, consists of a roup of che!ical substances called

4Tocopherols4. There are si different tocopherols %hich are collecti#ely called #ita!in '. Itoccurs as a yello% #iscous oil, insoluble in %ater, but soluble in fat sol#ents.

8. Fun'tion%The !etabolic roles of"#ita!in ' in the hu!an body are poorly understood. ;o%e#er, the

principal functions !ay be enu!erated.

i. Anti"o2idantThe principal role of #ita!in ' appears to be as an anti"oidant. By acceptin oyen,

#ita!in ' helps to pre#ent the oidation of polyunsaturated fatty acids and phospholipidsthereby helpin to !aintain the interity of cellular !e!branes.

ii. !parin, effe't on vitamin AVita!in ' plays and i!portant role in the protection of #ita!in A, carotene and ascorbic

acid fro! oidation in the diesti#e tract and in the body cells. By acceptin oyen itself, ithelps to pre#ent the oidation of #ita!in A. In the body tissues #ita!in ' plays another i!portantrole by reducin the oidation of the polyunsaturated fatty acids, thereby, helpin to !aintain theinterity of the cell !e!branes. Thus, the protecti#e property of #ita!in ' enhances the efficientuse of #ita!in A and ascorbic acid.

iii. A'tivator of en@*me%It is belie#ed that #ita!in ' also functions as an acti#ator in certain en?y!atic reactions.

h. !our'e%The principal sources of #ita!in ' in the diet are #eeetable oils (co!, soya, cotton

seeds, safflo%er. The hydroenated fats fro! these oils, %hole rains and dar+ reen leafy#eetables, nuts and leu!es. Foods of ani!al oriin are lo% in #ita!in ', li#er, heart, +idney,


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!il+ and es are the ani!al sources of this #ita!in. ;u!an !il+ pro#ides ade*uate #ita!in 'for the infant, but co%s !il+ contains #ery little of this #ita!in.

4. :itamin (Vita!in is an i!portant fat soluble #ita!in. Vita!in is found in nature in t%o for!s-

and / occurs in reen lea#es and is produced by bacterial synthesis Vita!in is often

called the 4Coaulation #ita!in4, because it has anti"he!orrhaic properties.

a. Fun'tion%Anti"he!orrhaic and synthesis of other proteins arelhe !aDor functions of #ita!in .

i. Anti"hemorrha,i' propert*Vita!in is also called as 4Coaulation #ita!in4 due to its anti"he!orrhaic properties.

This #ita!in is essential for the synthesis of pro"thro!bin, the precursor of thro!bin, one of thefactors needed for nor!al coaulatory function of the blood. A blood clot is !ade up of fibrin, aprotein %hich is deposited as fine threads to tor! a net %or+. The for!ation of fibrin tro!fibrinoen re*uires thro!bin and the for!ation of thro!bin fro! pro"thro!bin re*uires calciu!and Vita!in . Vita!in !ay be an essential part of the en?y!e syste! in#ol#ed in the

production of the blood clottin factor.

ii. !*nthe%i% of other protein%It is assu!ed that #ita!in is re*uired for the synthesis of other proteins containin r"

carboy luta!ic acid %hich ha#e been identified in bone and +idney. ;o%e#er, the functions ofthese proteins ha#e not been identified.

. !our'e%Vita!in !ainly occurs in plants reen lea#es of plants such as spinach and also

cabbae, cauliflo%er, soyabean and #eetable oils are ood sources of #ita!in . Cereals, fruitsand other #eetables are poor sources. Ani!al products contain !uch less #ita!in , but por+li#er is a ood source.

Since, this #ita!in is present in a lare #ariety of co!!only eaten plant foods and it canbe synthesi?ed in the intestinal tract by bacteria and because of its insolubility in %ater, thenor!al person does not usually suffer fro! #ita!in deficiency .

B. ater %olule vitamin%B"co!ple #ita!ins, and #ita!in C are the %ater soluble #ita!ins. B"Co!ple #ita!ins

include Thia!ine (B, @ibofla#in (B/, )iacin, Pyridoine (B3 Pantothenic acid, Biotin, B/,Folic acid.

B"$omple2 vitamin%The %ater soluble #ita!in B has been described as a lare roup of co!pounds, %hich

ha#e been desinated as the #ita!in B co!ple. &ainly, these #ita!ins co!bine %ith specificproteins to function as parts of the #arious en?y!e syste!s %hich are concerned %ith thebrea+do%n of carbohydrate, protein and fat in the body. ;ence, they are interrelated and areinti!ately in#ol#ed in the !echanis!s %hich release enery, carbondioide and %ater as theend"products of !etabolis!.

=enerally the %ater soluble #ita!ins are not stored in the body. 'cess are larelyecreted, thus eli!inatin the possible ties for toicity that eist %ith o#er dosae of fat soluble#ita!ins. So!e of B"co!ple #ita!ins are essential in hu!an nutrition and they !ust be


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pro#ided in our daily !eals. Three of these are included in the allo%ance for diet they areThia!ine (B, @ibofla#in (B/ and )iacin.

a. )hiamine ;:itamin B#ther fun'tion%In addition to its coen?y!e function, thia!ine !ay be in#ol#ed in so!e aspect of the

function of ner#e cell !e!branes or in so!e %ay influence the action of neuro"trans!itters such

as acetyl"choline or serotonin.

ii. !our'e%All the ani!al and plant tissues contain thia!ine in a s!all *uantity, but the only rich

sources are the seeds of plants li+e cereals, nuts, peas, beans and other pulses and in additionyeast. All reen #eetables, roots, fruits, flesh foods and dairy products (ecept butter containsinificant a!ounts of this #ita!in but none of the! are rich sources.

. Rioflavin ;:itamin B/ in the for!ation of purines, these

co!pounds bein essential constituents of 8)A and @)A.

;'< Help in 'aroh*drate metaoli%m$ithin the rebs cycle (TCA cycle, biotin is also re*uired for the con#ersion of

succinates to fu!arate and oalo"succinate to +etolutarate.

ii. !our'e%Biotin is found in !inute *uantities in foods li+e li#er, +idney, pancreas, !olasses, !il+,

yeast and e yol+. The precise daily re*uire!ents of biotin is not +no%n.

,. :itamin B#This #ita!in is the only cobalt"containin substance essential to life. This #ita!in is

absorbed fro! the ileu! only in the presence of a !uco"protein en?y!e produced by the astric!ucosa.

i. Fun'tion%Vita!in BI/ ha#e the follo%in functions.

;8< Help in 'ell fun'tionin,Vita!in BI/ functions in all cells, but especially those of the astro"intestinal tract, the

ner#ous syste! and the bone !arro%. $ithin the bone !arro% a #ita!in BI/ co"en?y!e Eparticipates in the synthesis of 8)A.

;< !*nthe%i% of nu'lei' a'id and nu'leo"protein%Vita!in BI/ is stored in the li#er and helps in the synthesis of nucleic acid and nucleo"

proteins.

;'< 1aturation of red lood 'ellVita!in BI/ is essential for the !aturation of red blood cells in the bone !arro%.

;d< 1etaoli%m of nervou% ti%%ueVita!in BI/ is essential for the !etabolis! of ner#ous tissue.

;e< $he'k perni'iou% anameiaPresence of #ita!in BI/ in the diet helps to pre#ent pernicious ane!ia. Pernicious

ane!ia results %hen there is deficiency of #ita!in BI/ in the diet.

ii. !our'e%


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Vita!in BI/ occurs in !inute concentrations in ani!al tissues but is absent in plantsfoods. Li#er and +idney contain 15 "25 u per 55 !. &il+, es cheese and !uscle !eatscontain "2 u per 55 !.

h. Foli' a'idFolacin is the ter! used for folic acid, pteroyl luta!ic acid and other co!pounds ha#in

the acti#ity of folic acid. 'tra a!ounts of folic acid in diet are ecreted in the urine and faeces.

i. Fun'tion%Follo%in three i!portant functions are of sinificance.

;a< $onver%ion into a'tive formFolic acid is transfor!ed into bioloically acti#e folic acid by ascorbic acid.

;< !*nthe%i%Folic acid also participated in the synthesis of purines, pyri!idines and nucleoproteins.

;'< $he'k% anemia

Its deficiency in !an is not li+ely to occur fro! dietory defects but !ay be secondary tocondition li+e !ealoblastic ane!ia to infancy and prenancy.

;d< DNA %*nthe%i%Folacin is essential to 8)A synthesis, and thus, toether %ith #ita!in BI/ reulates the

for!ation of nor!al red blood cells in the bone !arro%.

ii. !our'e%Folic acid is found in foods both in the free for! and in the conDunated for!. Li#er,

+idney, deep reen leafy #eetables are food sources of this #ita!in. $heat, cereals pro#ides afair a!ount of it. @oot #eetables dairy foods, por+ and liht reen #eetables are poor sourcesof this #ita!in.

i. A%'ori' a'idAscorbic acid also +no%n as #ita!in C is one of the !ost i!portant %ater soluble

#ita!ins. Ascorbic acid is a co!" pound and is closely related to the !ono"saccharide suars. Itcan be prepared at lo% cost fro! lucose. Loss of this #ita!in often results fro! storae,processin and coo+in.

i. Fun'tion%So!e of the i!portant functions are eplained in detail.

;a< Formation of 'olla,en>ne of the principal functions of Ascorbic acid is the for!ation of collaen, an abundant

protein that for!s the inter"cellular substance in cartilae, bone !atrices, dentin, and the#ascular epitheliu!.

;< ound healin,Ascorbic acid helps in %ound healin and the ability to %ithstand the stress of inDury and

infection.

;'< 1etaoli' pro'e%%


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Ascorbic acid helps in the nor!al !etabolis! of the a!ino"acid, tyrosin and in thefunction of the adrenal land.

;d< A%orption of ironAscorbic acid helps in the easy absorption of iron fro! the astrointestinal tract by the

reduction of ferric iron to ferrous iron.

;e< A% an anti"o2idantAscorbic acid is an i!portant anti"oidant and thus has a role in the protection of

#ita!ins A and ' and the poly saturated fatty acids fro! ecessi#e oidation.

;/< >ther fun'tion%Ascorbic acid plays an i!portant role in synthesis of !ucopoly saccharides, !icroso!al

dru !etabolis! leu+ocyte function and synthesis of anti infla!!atory steroids by the adrenallandE

ii. !our'e%Fruits and #eetables are the !ain sources of ascorbic acid. Citrus fruits (oranes,

rapes, le!ons and li!es berries, #eetables, reen pepper, cabbae, chilies, !anoes, a!la,to!atoes are ood sources. 8ry leu!es, contain s!all a!ount of ascorbic acid their ascorbicacid content increases durin er!ination.

&il+, es, !eat and poultry, as they are consu!ed, do not ha#e any #ita!in C(Ascorbic acid. ;u!an !il+ contains four to si ti!es as !uch ascorbic acid as co%s !il+ toprotect the infant fro! scur#y. Li#er contain a s!all a!ount of ascorbic acid, but it is nor!allylost in coo+in.

:/. ater

$ater is an i!portant constituent of our diet. It is interestin to note that about 927 of an

infants body and 357 of an adult body is co!posed of %ater. Loss of 2 to /57 %ater !aypro#e to be fatal.

A. Fun'tion% of water.$ater is one of the !aDor structural constituents of our body. All the tissues of our body

includin teeth and bone, contain %ater.

#. Help% in metaoli%mThere are #arious !etabolic processes (physico"che!ical chanes ta+in place in our

body. $ater acts as a !ediu! for these reactions. The %aste production of the body areecreted in the for! of urine and perspiration and %ater is the !ediu! for both of these.

. A't a% a 'arrier$ater is a carrier for the products of diestion helpin in transportin the! to the #arious

cells in the body.

3. 1aintain% od* temperature$ater helps in !aintainin the body te!perature by distributin the heat in the body.

4. uri'ant


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$ater is aft i!portant lubricant for the #arious orans. &ucous that lubricates thediesti#e tract and the respiratory tract, sali#a %hich !a+es it possible for us to s%allo% the"food, all contain %ater as an i!portant constituent.

B. !our'e% of waterThe body suffers loss of %ater due to ecretion in urine, faeces and perspiration. So!e

of the %ater is also lost %ith the air that %e ehale. To !a+e up the losses one has to ta+e %aterin the diet. Fats, carbohydrates and proteins all contain %ater in so!e for! or the other.

Besides these, the #arious che!ical reactions oin on in our bodies also release %ater%hich can be used. About .2 litres of %ater per day is sufficient to co#er the losses fro! thebody and !eet its re*uire!ents.

://. 1ineral lement%A lare nu!ber of !inerals are present in the hu!an body. &inerals are those ele!ents

that re!ain larely as ash %hen plants or ani!al tissues are burned. &acronutrients are thosethat are re*uired in appreciable a!ounts and account for !ost of the body content of !inerals.&icro nutrients (Trace ele!ents are re*uired in !inute a!ounts. The functions and sources of

i!portant !inerals are eplained here.

A. $al'iumThe body contains !ore calciu! than any other !ineral. Calciu! and phosphorus

account for 92 percent of total !ineral ele!ents in the body.

#. Fun'tion%Calciu! and phosphorus are !ainly present in bones and teeth and the reulation of

certain body processes. The need for calciu! in the buildin of the s+eleton is, reater durinthe years of ro%th. The nor!al functionin of heart !uscles, ner#es and the blood clottinprocesses all depend on the presence of calciu!.

. !our'e%&il+ and !il+ products are ecellent sources of calciu!. =reen leafy #eetables such as

carrot lea#es, !int, spinach, a!aranth and !ustard lea#es are net to the dairy products in theircalciu! content. Citrus fruits, leu!es, !eat, rain and nuts pro#ide the least calciu!.

B. &ho%phoru%

Phosphorus is an i!portant constituent in e#ery body tissue. The total a!ountconstitutes about one percent of the body %eiht. The a!ount of phosphorus in the body iseceeded only by calciu!. In bones the proportion of calciu! to phosphorus is about /-. Inbody fluids and soft tissues the proportion of phosphorus is !uch hiher than that of calciu!.

#. Fun'tion%Phosphorus is one !ineral that perfor!s a nu!ber of i!portant functions. It co!bines

%ith calciu! to for! a co!pound, %hich i#es strenth and riidity to bones and teeth. It alsohelps in its !aintenance. A series of phosphorus co!pounds are for!ed in the utili?ation ofcarbohydrates in the body. It is #ital to the funda!ental processes of !etabolis! in the body.Phosphorous is a constituent of the nucleo"proteins.

. !our'e%


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Phosphorus is %idely distributed in both plant and ani!al foods. 8iets rich in protein andcalciu!, pro#ide sufficient phosphorus. 's, !il+, !eat, poultry, fish and flour are ecellentsources of phosphorus. $hole rain cereals, and flour pro#ide phosphorus in ood a!ount.Veetables and fruits are lo% in phosphorus content.

A part of the phosphorus in cereals, pulses and nuts is present as phytin that is not

a#ailable to the body. Phytin also interferes %ith the absorption of iron and calciu!.

$. &ota%%iumPotassiu! is !ostly found in cells of the body. The re!ainin is distributed in the etra

cellular fluid. Plas!a also contains s!all a!ounts of potassiu!. Potassiu! is present in larea!ounts in the diesti#e Duices. 'cess potassiu! is ecreted fro! the +idneys.

#. Fun'tion%Potassiu! !aintains os!otic pressure and fluid balance %ithin the body cells. It is

needed for the synthesis of proteins. It is necessary for the en?y!atic reactions %ithin cells.So!e of it is bound to phosphates. In the bound for! potassiu! is necessary for the con#ersionof lucose to lycoen. 8urin lycoenolysis (brea+do%n of lycoen the potassiu! ets

released.

. !our'e%&eat, poultry and fish are ood sources. Fruits, #eetables and %hole reen cereals are

also ood sources of this !inerals. Bananas, potatoes, to!atoes, carrots, celery, orane Duice,rape fruit contain potassiu! in appreciable a!ounts.

D. !odiumSodiu! is present in !any foods in the for! of sodiu! chloride. The absorption of

sodiu! chloride %hich is an inoranic salt in the diet occurs in the astro"intestinal tract rapidlyand is practically co!pleted there. The +idneys reulate the sodiu! le#el in the body. $hen thesodiu! inta+e is hih, ecretion is also hih. If sodiu! is restricted in the diet, the ecretion of

sodiu! by the healthy +idney is absent and thus sodiu! is conser#ed co!pletely in the body.

#. Fun'tion%Sodiu! !aintains nor!al os!otic pressure and %ater balance as it is the principal

electrolyte in etra"cellular fluid. It is essential for the !aintenance of the p; of the astro"intestinal secretions. The reulation of the per!eability of the cell !e!brane is due to sodiu!.The sodiu! helps to !aintain electrolyte differences bet%een intracellular and etra"cellularfluids.

. !our'e% of %odiumCo!!on salt or sodiu! chloride is the chief source of sodiu! in the diet. It is found in

ani!al foods, such as !il+, es, !eat, fish, poultry and in #eetables, such as spinach,

fenuree+, pulses, celery. &ost of the cereals fruit and leu!es are poor sources of sodiu!.

. $hlorineThis is present in the body as the chloride ion. It is present in etracelluar fluid as sodiu!

chloride. It is found %ithin the cells as potassiu! chloride. Chloride ions are present in red bloodcells. It is an essential constituent of the astric Duice.


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/#. Fun'tion%Chlorine is i!portant for the reulation of os!otic pressure. Chloride helps to !aintain

the %ater balance and p; balance. They acti#ate sali#ary a!ylase chloride the acid !ediu! foracti#ation of the astric en?y!es and diestion in the sto!ach.. !our'e%

&ost of the chloride ta+en is fro! the co!!on salt used durin food processin andpreparation.

F. 1a,ne%iumThe a!ount of !anesiu! present in the body is less than that of calciu! and

phosphorus. The dietary absorption of !anesiu! is about 15 percent. A hih calciu! inta+eincreases the re*uire!ent for !anesiu! as %ell. 'cess is ecreted fro! the +idneys.

#. Fun'tion%&anesiu! is re*uired for all li#in cells. It is a catalyst for nu!erous bioloical reactions

in#ol#in the release of enery. It is a constituent of bone. It is essential for nor!al !etabolis!of calciu! and phosphorus. Its presence in etra" cellular fluid reulates the trans!ission of

ner#e i!pulses.

. !our'e%8airy products, ecludin butter, pro#ide enouh !anesiu!. Flour and cereal products,

dry beans, soya beans, peas and nuts are ood sources. =reen leafy #eetables are ecellentsources of it because !anesiu! is a part of chlorophyll.

G. /ronIron is the chief a!on the trace ele!ents re*uired for the body. The total content of iron

is #ery s!all in the body. It is %idely distributed throuhout the body. The !aDor portion of it isfound in the blood as hae!olobin. &uscle tissue contains about 0 percent of iron as !yolobinand the rest is stored in the li#er, spleen, +idney and bone narro%.

#. Fun'tion%Iron is essential for the oidation in the body. It is a constituent in co!pounds necessary

for the transport of oyen to the cells and for oidation in the cells. In the body iron is present inthe blood or li#er. The hae!olobin of blood is a co!pound of hae!e, an iron co!pound and4lobin4, a protein. The synthesis of hae!olobin is based on iron in the body.

Iron is also a constituent of plas!a %here iron is bound to a protein called transferrin.Iron is present in the !uscle cells or t%o co!binations, as !yolobin and as a constituent ofhae!e en?y!es.

Iron containin en?y!es in !uscles !a+e the oidation of carbohydrates, fat and protein

%ithin the cell. It carries oyen to the cells in hae!olobin and !a+es oidation possible in thecells throuh the iron "containin en?y!es.

. !our'e%' yol+ and oran !eats are ood sources of iron. Li#er is an ecellent source of iron.

&eat, Daery, raisins and dried fruits are also a ood source of iron. A!on food rains baDra isa ood source. Fresh and canned fruits and other #eetables contain #ery little iron. Spicessuch as !ustard, cu!inseed, fenuree+, celery seeds and coriander contain liberal a!ounts of


24/25

iron but their consu!ption in daily diet is #ery little so they do not !a+e a sinificantcontribution.

H. 1an,ane%e&ananese is a trace ele!ent %hich is re*uired in s!all a!ounts in the diet. It is poorly

absorbed fro! the s!all intestine. &ananese is transported by the blood as a loosely bound

protein co!pound +no%n as trans!ananin. It is ecreted as a constituent of bile !ost of it isaain re"absorbed and retained in the body. The a!ount ecreted by urine is #ery s!all.

#. Fun'tion%&ananese acti#ates a nu!ber of en?y!es that helps in the for!ation of urea. It for!s

the en?y!e peptidases responsible for the hydrolysis of proteins in the intestine. &ananese isassociated %ith s+eletal de#elop!ent, lipid !etabolis!, control of ner#ous irritability.

. !our'e%)uts, leu!es, %hole"rain cereals contain !ananese. Ani!al foods are poor sources

of this !ineral.

/. $opperThe tissues of the body contain it in traces but the hihest a!ount is found in the brain

and li#er. The a!ount found in the adult body is about 55 !. About :2 per cent of copperpresent in blood plas!a is found fir!ly bound in a protein co!ple, ceruloplas!in, and there!ainin 2 percent loosely bound to another protein, albu!en. &ost of the copper is ecretedthrouh the bile in faecal !atter.

#. Fun'tion%Copper is re*uired for #arious functions includin the for!ation of the pi!ent !elanin in

the s+in. It helps in the transport of electrons. It !aintain the strenth of the !yelin sheathco#erin the ner#es. Copper helps in the synthesis of phospho"lipids. It is necessary for thefor!ation of hae!olobin in the blood alon %ith iron. It is a constituent of en?y!es in#ol#ed in

the oidation of fatty acids. It is necessary for healthy hair.

. !our'e%'#en the poor pro#ide enouh copper for hu!an re*uire!ents. A!on rich sources are

oran !eals, shell fish, %holerain cereals, leu!es and nuts. &il+ is a poor source.

. /odineAbout one"third of the iodine present in adults occurs in the thyroid land. Iodine is

inested in foods as inoranic iodides and as oranic co!pounds. 8urin the process ofdiestion, iodine is split fro! oranic co!pound and is absorbed as inoranic iodides. Theiodine is released into the circulation durin cellular oidation. About one third of the iodine thusreleased is retained to be used aain or thyroid hor!one and the re!ainder is ecreted throuh

urine.

#. Fun'tion%It is a constituent of the thyroid land %hich controls the rate of enery utili?ed in the

body or the basal !etabolic rate. Iodine is essential for synthesis of the thyroid hor!one,thyroine. Thyroine is bound to the lobulin and is stored as thyrolobulin in the land.Thyroine reulates the rate of oidation %ithin the cells thereby sti!ulatory physical and !entalro%th, functionin of ner#e and !uscle tissue, circulation of blood and !etabolis! of allnutrients.


25/25

. !our'e%Iodine is enerally supplied by food and %ater, fro! the soil rich in iodine. The !ost

i!portant dietary source of iodine is iodised salt. Sea%eed, salt %ater fish and shell"fish containi!portant a!ounts of iodine. The iodine content of es, dairy products, and !eats dependsupon the iodine content of the ani!als diet. Veetables ro%n on iodine"rich soils near the sea

coast are ood sources of iodine, those ro%n on iodine poor soils, contain little iodine.

(. Cin'It is found in traces in all body tissues. The hihest concentration of it occurs in the li#er,

pancreas, +idneys and brain. It is also present in the red blood cells and blood seru!. inc ispoorly absorbed fro! the intestine and !ost of it is ecreted in the faeces. A s!all a!ount ofthis is also ecreted in the urine. A hih calciu! and phytate inta+e interferes %ith the absorptionof ?inc.

#. Fun'tion%inc is re*uired for protein synthesis and also 8)A and @)A synthesis in body cells.

inc accelerate the process of healin of %ounds. It co!bines %ith the hor!one insulin but it is

not re*uired for the acti#ity of insulin.

. !our'e%inc is %idely distributed in both ani!al and #eetable foods. @ich sources include li#er,

hih proteins foods, %hole rain cereals, beef, la!b and por+. Leu!es, peanuts and peanutbutter are ood sources, but fruits and !ost #eetables are poor sources. The ?inc in plantproteins is less a#ailable than that in ani!al proteins.

. FluorineIt is one of the !ost acti#e ele!ents. Traces of fluorine are present in bones, teeth,

thyroid land and s+in. It protect the teeth fro! decay.

#. Fun'tion%A proper inta+e of fluorine is #ery essential to pre#ent dental caries. Fluorine is re*uired

for nor!al !ineralisation of bones.

. !our'e%The !ain sources of fluorine is the drin+in %ater. It occurs in traces in !any foods but

so!e foods such as seafish, cheese are rich sources of fluorine.

77777777777777

nutrient requirement for human growth-304

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