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NUTRITION

CALORIFIC VALUE

1. Defne calorifc value. Pon Nov 2006

2. ive !"e calorifc value# o$ car%o"&'ra!e# an' $a!. Pon (a& 200)* (a&

200+

1. Calorie is the unit of heat. One calorie represents the amount of heat required to

rise the temperature of one gram of water by l0 C. In medical practice, the energy

content is usually expressed in kilocalorie kcal or C! which is equal to 1000

calories. 1 Cal 1 kcal! " #.1$% &'

$. Caloric (alue is de)ned as amount of heat energy obtained by burning 1.0 gm of

the food stu* completely in the presence of O$.

+. Caloric (alue of di*erent foodstu*s is determined in (itro in a special apparatus

called bomb calorimeter.

#. Caloric values

a. Carbohydrate #

b. -at

c. /rotein #.$

d. lcohol

,A-AL (ETA,OLIC RATE

1. Defne ,(R. "a! i# !"e nor/al ,(R o$ an a'ul! Li#! 6 $ac!or# !"a! aec!

,(R. Pon Nov 20112. Defne ,(R. "a! i# !"e nor/al value#. Li#! !"e $ac!or# aec!in ,(R. Pon

(a& 2010

). Na/e !3o con'i!ion# 3"ic" increa#e ,(R. Pon (a& 2004

2an consumes energy to meet the fuel demands of the three ongoing processes in the

body.

1. 3asal metabolic rate

$. 4peci)c dynamic action

+. /hysical acti(ity

,a#al /e!a%oli#/5 5he basal conditions are as follows

1. /erson should be awake but at complete rest6both physical and mental.

$. /erson should be without food at least 1$ to 1% hrs, i.e. in the 7postabsorpti(e

state8.

+. 4hould be in recumbent9reclining position in bed.

#. /erson should remain in normal condition of en(ironment, i.e. at normal

temperature, pressure and humidity

,a#al (e!a%olic Ra!e5

$1

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1. Defni!ion 5he basal metabolic rate is the energy required by an awake

indi(idual during physical, emotional and digesti(e rest.

$. It is the minimum amount of energy required to maintain life or sustain (ital

functions like the working of the heart, circulation, brain function, respiration, etc.

 5he metabolic rate during sleep is less than 32:.

+. :esting metabolic rate :2:! is the measure of energy required to maintain life or

(ital functions. 5he sub;ect is awake and nonfasting. It is approximately about +<

higher than the 32:.

#. 32: is measured directly by the heat e(ol(ed, or indirectly by the (olume of

oxygen consumed and carbon dioxide e(ol(ed per unit time.

(ea#ure/en! o$ ,(R5

1. sub;ect is awake, physically and mentally at rest, and is in post absorpti(e state.

 5he 32: is calculated from oxygen consumption, calori)c (alue and surface area.

1. /rocedure 3enedict :oth method and =ouglas bag open circuit! methods

$. 3enedict>:oth closed circuit method the (ol. of O consumed for $>? minutes under

basal conditions is measured by graphic recordings. One liter of O$ produces

#.%$@ cal. Aeat produced in ? minutes will be #.%$@ x 10 x (ol. of O$ in liters. It is

expressed as Cal9sq.m of body surface9hour

Nor/al value#5

1. dult male +@>+% cal9sq.m9hr.

$. dult female +$>+@

+. B or > 1@ < of this could be taken as normal range.

#. dult male 1?00 cal9day female 1#009day is another simpli)ed representation of

this (alue.

Fac!or# aec!in ,(R5

1. 3ody surface area is directly proportional to 32:.

$. 4ex male is @< higher 32:

+. Infants and children ha(e comparati(ely high 32:

#. xercise increase 32:

@. 5hyroxin increases 32: as seen in hyperthyroid state.

?. Cold climate increases 32:

. 4tar(ation leads to reduction in 32: as part of adaptation.

%. -e(er increases 32:D 10 < increase for 1.C

. 32: is ele(ated in infections.10. In skimos it is higher.

-inifcance o$ ,(R it helps to calculate calorie requirement and diet calculation. It

helps to asses thyroid function.

-PECIFIC DNA(IC ACTION

1. Defne -DA. "a! i# !"e -DA $or eac" o$ !"e %ul7 ele/en! o$ !"e $oo' Pon

Nov 2010

$$

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2. Defne -DA. (en!ion i!# #inifcance. Pon Nov 2006

1. =e)nition 5he phenomenon of the extra heat production by the body, o(er and

abo(e the cafculated caloric (alue, when a gi(en food is metaboliEed by the body, is

known as speci)c dynamic action 4=!.

$. -or eg. person takes $@ gm of protein the energy produced should be 100 cal. 3ut

the body liberates 1+0 calories. 5his extra calorie is the 4= of protein. /rotein has

the highest (alue.

1. Cal of 4= is an acti(ation energy needed for digestion, absorption, transport,

metabolism and other chemical reactions and is deri(ed from pre(ious food energy.

$. 4= (alues for each 100 calories

-at " 11+ cal

Carbohydrate " 10@ cal

/rotein " 1+0 cal

2ixed diet " 110 cal

+. 4= for mixed diet -or a mixed diet, the 4= is not an additi(e (alue of di*erent

foods but it is much less. 5he presence of fats and carbohydrates reduces the 4= of

proteins. -ats are most eFcient in reducing 4= of foodstu*s. -or a regularly

consumed mixed diet, the 4= is around l0

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limiting the caloric intake. utritionists are of the opinion that foods with high )ber

content and low glycemic index should be preferred for consumption

+. E9a/:le# o$ l&ce/ic in'e95

1. Hlucose 100

$. 3read, rice 0>%0

+. 3anana, potato ?0>0

#. OrangeD apple #0>#@

@. Gce cream, milk +@>#0

DIETAR FI,ER

 5he una(ailable or indigestible carbohydrate in the diet is called dietary )ber.

,enefcial eec!# o$ f%er#5

1. =ietary )ber is necessary to maintain the normal motility of gastrointestinal tract.

$. =iet rich in )ber impro(es bowel motility, pre(ents constipation.

+. -iber adsorbs large quantities of water and also the toxic compounds produced by

intestinal bacteria that lead to increased fecal mass and its easier expulsion.

#. 5he lower incidence of cancers of gastrointestinal tract e.g. colon and rectum! in

(egetarians compared to non>(egetarians is attributed to dietary )ber.

@. -iber impro(es glucose tolerance by the body. 5his is mainly done by a diminished

rate of glucose absorption from the intestine.

?. -iber decreases the absorption of dietary cholesterol from the intestine. -urther,

)ber binds with the bile salts and reduces their enterohepatic circulation. 5his

causes increased degradation of cholesterol to bile salts and its disposal

from the body.

. 5he bene)cial e*ect is more with soluble )ber present in (egetables and only a

diet ha(ing plenty of (egetables and green lea(es will ha(e the desired e*ect.

Re;uire/en!5

-iber requirement is about +0 g9day. 5he inclusion of )ber rich food in weight

reducing diets is found to be helpful, since it pro(ides a feeling of fullness without

consumption of excess calories.

-ource#5 -ruits, Geafy (egetables, (egetables, whole>wheat legumes, rice bran etc.

A'ver#e aec!# o$ f%er5

a. =igestion and absorption of protein are ad(ersely a*ected.

b. 5he intestinal absorption of certain minerals e.g. Ca, /, 2g! is decreased.

c. Intestinal bacteria ferment some )bers, causing Jatulence and often

discomfort

 

E--ENTIAL FATT ACID-

 5he unsaturated fatty acids which the body cannot synthesiEe and, therefore,

$#

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must be consumed in the diet are referred to as essential fatty acids -!.

Func!ion# o$ EFA

1. ssential fatty acids are the structural components of biological membranes.

$. /articipatei n the transporta nd utiliEation of cholesterol.

+. /re(ent fat accumulation in the li(er.

#. :equired for the synthesis of prostaglandins

@. 2aintain proper growth and reproduction of the organisms

Defcienc& o$ EFA

1. ssential fatty acid de)ciency is associated with se(eral complications. 5hese

include impairment in growth and reproduction, increased 32: and high turno(er

of phospholipids.

$. 5he - de)ciency is characteriEed by a scaly dermatitis on the posterior and

lateral parts of limbs and buttocks, referred to as phrynoderma or toad skin.

+. /oor wound healing and hair loss is also obser(ed in - de)ciency.

EFA con!en! o$ $oo'#

1. 5he essential fatty acids, also called polyunsaturated fatty acids /K-!, are

present in (egetable oils and )sh oils.

$. 5he sources include sunJower oil, cofton seed oil, corn oil, soyabean oil etc. 5he

fat of animal origin exception>)sh!, contain less /K- e.g. butter, fat of meat, pork

and chicken.

Die!ar& in!a7e o$ EFA

1. +0< of the dietary fat should contain /K-.

$. xcess /K-, unless accompanied by antioxidants (itamin , carotenes! is

in;urious to the cells due to the o(erproduction of free radicals.

PROTEIN-

CO(PLETE PROTEIN

1. "a! 'o &ou /ean %& co/:le!e :ro!ein ive e9a/:le. Pon Nov 2006

1. complete protein contains an adequate amount of all of the essential amino acids

that should be incorporated into a diet.

$. nimal proteins are complete proteins as compared to those of (egetable proteins

Incomplete proteins!.

+. Lhole egg and milk proteins, specially Gactalbumin rank highest in this respect and

they contain the highest percentages of the 7essential amino acids8.

#. 2eat, )sh, poultry and glandular tissues occupy next position in the scale. In the

same class, are also yeast and soyabean.

@. Cereals, legumes peas, beans, etc! and nuts are generally poor because they lack

some essential amino acids and thus they are incomplete proteins and are of poor

quality.

$@

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NITROEN ,ALANCE

1. "a! 'o &ou /ean %& !"e !er/ ni!roen %alance "ic" are !"e

con'i!ion# in 3"ic" :o#i!ive ni!roen %alance i# o%#erve' Pon A:r 2002

1. normal healthy adult is said to be in nitrogen balance, because the dietary intake I!

equals the daily loss through urine K! feces -! and skin 4!.I " K B - B 4

$. Lhen the excretion exceeds intake, it is negati(e nitrogen balance. Lhen the

intake exceeds excretion, it is a state of positi(e nitrogen balance.

+. itrogen balance can be measured by calculating the dietary intake of protein

nitrogen 1?< of the weight of protein! and measuring the daily excretion.

4. Fac!or# Aec!in Ni!roen ,alance

a. ro3!" =uring the period of acti(e growth, a state of positi(e nitrogen balance

exists. On an a(erage when a person gains @ kg, about 1 kg proteins are added to

the body.

b.

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result is that some amount of nitrogen is lost from the body depleting the body

protein.

b. /rolonged negati(e nitrogen balance may e(en lead to death. 5his is

sometimes obser(ed in children su*ering from kwashiorkor or marasmus.

c. egati(e nitrogen balance may occur due to inadequate dietary intake of

protein de)ciency of e(en a single essential amino acid! or destruction of

tissues or serious illness. In all these cases, the body adapts itself and

increases the breakdown of tissue proteins causing loss of nitrogen from the

body.

%. Other factors inJuencing nitrogen balance

Aormones Hrowth hormone and insulin promote positi(e nitrogen balance while

corticosteroids result in negati(e nitrogen balance.

=isease states Cancer and uncontrolled diabetes cause negati(e nitrogen

balance.

,IOLOICAL VALUE =,V> OF PROTEIN

1. Defne %ioloical value# o$ :ro!ein. Pon (a& 2010

1. It is the ratio between the amount of nitrogen retained and nitrogen absorbed during

a speci)c inter(al.

3M " :etained nitrogen N 100

  bsorbed nitrogen

$. -or the measuremenot f 3M, the experimental animals, namely weaning albino rats

are chosen 4uppose 1$ mg of a particular protein was consumed by a rat in a day

and # mg is reco(ered in feces and $# mg is seen in urine. 5hen

mount ingested " 1$ mg

mount absorbed " 1$ # " 1$+ mg

mount retained " 1$+ $# " mg

 5herefore 3M " 91$+ N 100 " %1<

+. 3iological (alue can be calculated by the following formula

3M " absorbed> lost in metabolism! x 100

absorbed

4.  5he 3M for di*erent protein sources

a. gg protein #

%. 2ilk protein %#

c. -ish %@

'. 2eat @

e. :ice ?%

$. 3engal gram @%

. 4oya ?@

@. 5he biological (alue pro(ides a reasonably good index for the nutriti(e (alue of

$

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proteins.

?. 5he drawbacks It cannot take into account the nitrogen that might be lost during the

digestion

. et protein utiliEation /K! is a better nutritional index than biological (alue, since it

takes into account the digestibility factor. 5he experimental procedure for /K is

similar to that of 3M. et protein utiliEation can be calculated as

/K " itrogen retained x 100

 itrogen ingested

(UTUAL -UPPLE(ENTATION OF PROTEIN-

1. "a! 'o &ou /ean %& !"e !er/ /u!ual #u::le/en!a!ion o$ :ro!ein# Pon

A:r 2002

2. "a! i# !"e nu!ri!ional %a#i# $or ine#!in co/%ina!ion o$ cereal# an'

:ul#e# Pon Dec 200)

1. Li/i!in a/ino aci'#5 Certain proteins are de)cient in one or more essential

amino acids. If this protein is fed to a young rat as the only source of protein, it fails

to grow. 5his amino acid is said to be the limiting amino acid. Gimiting amino acid is

that which limits the weight gain when a protein is supplied to an animal

$. 5he animal proteins are superior in their nutriti(e (alue compared to the proteins of

(egetable origin. 3ut some of the essential amino acids are limiting in (egetable

proteins. -or instance, rice and wheat proteins are limiting in lysine and threonine

while the protein of 3engal gram is limited in sulfur>containing amino acids

methionine and cystine!.

+. 5his problem can be o(ercome by supplementation of the essential amino acids in

one food to the other that lacks such essential amino acids. 5his phenomenon is

referred to as mutual supplementation.

#. xample diet with cereals wheat, rice! is taken along with pulses dal!. 5he

limitation of lysine and threonine in cereal proteins is o(ercome by their

supplementation from dal proteins. 4imultaneously, the limitation of sulfur containing

amino acids in dal is also compensated by the cereals, which are rich in them.

@. 5he principle of mixed diet takes care to supply adequate quantities of essential

amino acids to the people subsisting on pure (egetarian diets. lt has to be

remembered that the e*ect of mutual supplementation in proteins is best obser(ed

with the same meal or on the same day.

PRE-CRIPTION OF DIET

1. Calcula!e !"e 'ail& ener& re;uire/en! o$ a 20 &ear ol' #u'en!. Pon Nov

2011

Ener& re;uire/en! o$ (AN or calcula!ion o$ &our ve. 'ie!

eneral Princi:le#5

$%

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1. Ideal body weight

i. 2ale of 1@+ cm height " #% kg B or > 1.$@ kg for e(ery cm!

ii. -emale of 1@+ cm height " #@ kg B or > 1 kg for e(ery cm!

$. /rotein requirement 1 gm 9 kg

+. Calorie requirement +0 to +@ &cal 9 kg of expected not actual! body wt

#. 4peci)c dynamic action xtra energy is to be supplied to account for 4=.

@. 3alanced diet means to contain ?0< carbohydrateD $0< fat and $0 < proteins

4tep 1

?0 kg maleD require ?0x+0 " 1%00 &cal B 10 < for 4= " 1%0D total requirement

is rounded of to $000 &cal.

4tep $

/rotein 1 gm9kg to pro(ide ?0 gm x # C! $#0 &cal ?0 gm

-at to pro(ide $0< of 1?0D $000 minus $#0 " 1?0! +@0 kcal +@09 " +@

gm

Carbohydrate to pro(ide 1#10 C 1?0 > +@0 " 1#109#" +$0! 1#00 kcal 1#009#"

+@0 gm

Calcium " #00 mg

Iron " $@ mg

4tep +

Co/:o#i!ion cereals and pulse ratio is @1

Cereals " +@0 gm

/ulses " @ gm

Oil " #0 ml

2ilk " $@0 ml

Geafy (egetables " $00 gm

4ugar " $@ gm

4tep #

4er(ings

/roteins in gms CA$O in gms

nergy in &cal ,rea7 $a#!5

$ chappatis or $ idlis " # +0 1#0

  100 ml milk " + @ ?0

@0 gm channa " 1$ +0 10

Lunc"5 100 gm :ice " 10 @

+@0

 @0 gm 3engal gram " 1$ +0 10

 1 3anana " $ 10 @0

 100 gm Hreen leafy (eg " $ # $0

Dinner5

  $ chappatis or $ idli s " # +0 1#0

$

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  @0 gm rice " @ +@ 1@

  @0 gm green gram " 1$ +0 10

  100 ml milk " + @ ?0

  1 3anana " $ 10 @0

  @0 gm oil " > > #@0

  10 gm 4ugar " > 10 #0

  100 gm Hreen leafy (eg " $ # $0

 

To!al ? @) )0) 206+

PROTEIN CALORIE (LNUTRITION

1. "a! i# 3a#"ior7or "a! are !"e c"ane# $oun' in !"e :la#/a o$ a

c"il' 3i!" !"i# 'i#or'er. Pon Nov 200@B

A-

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?. Aypokalemia is associated with dehydration.

. Aypomagnesemia is often seen.

. 5reatment

1. a planned diet manipulation by pro(iding 1@0>$00 &cal and +># gm protein per kg

body weight under super(ision is the ideal treatment. mixture of + parts of

(egetable proteins and 1 part of milk protein is often used.

%. 4equelae relapse is commonD intellectual capacity may be reduced permanently.

 

+01