NECESSITY FOR A BALANCED NECESSITY FOR A BALANCED DIET DIET

Balanced dietBalanced diet : contains the correct : contains the correct proportions of all the different food proportions of all the different food requirements (requirements (7 classes of food7 classes of food) of the ) of the bodybody

Should supply enough energy for each Should supply enough energy for each day’s activity (60% carbohydrates, 20% day’s activity (60% carbohydrates, 20% fats & 20% protein)fats & 20% protein)

Food requirementsFood requirements in a balanced dietin a balanced diet

1.1. Carbohydrates & lipidsCarbohydrates & lipids to provide energy for all to provide energy for all activities in the bodyactivities in the body

2.2. ProteinsProteins to build new tissues for growth & repair to build new tissues for growth & repair damaged or dead tissuesdamaged or dead tissues

3.3. VitaminsVitamins to prevent diseases & for normal to prevent diseases & for normal healthy developmenthealthy development

4.4. Mineral saltsMineral salts which are essential for normal which are essential for normal healthy & developmenthealthy & development

5.5. FibresFibres as roughage to stimulate peristalsis & as roughage to stimulate peristalsis & prevent constipationprevent constipation

6.6. WaterWater which is needed as the medium for all which is needed as the medium for all chemical reactions in the cells. It helps to chemical reactions in the cells. It helps to transport substances, to distribute & regulate transport substances, to distribute & regulate body heatbody heat

DAILY ENERGY REQUIREMENTDAILY ENERGY REQUIREMENT Energy required Energy required to carry out all living processesto carry out all living processes (the (the

heart beating, breathing, growing, excreting & maintaining heart beating, breathing, growing, excreting & maintaining body temperaturebody temperature

The energy is obtained from the oxidation of molecules The energy is obtained from the oxidation of molecules from food during cellular respirationfrom food during cellular respiration

Unit for Unit for energyenergy : : Joule (J)Joule (J)

Energy valueEnergy value / caloric value : the / caloric value : the quantity of heat quantity of heat produced when one gram of food is completely oxidisedproduced when one gram of food is completely oxidised

Unit for Unit for energy value : joules per gram (J genergy value : joules per gram (J g-1-1)) Energy value = mass of water (g) x increase in Energy value = mass of water (g) x increase in

temperature (temperature (ooC) x 4.2 J gC) x 4.2 J g-1-1 ooCC-1-1

mass of food (g)mass of food (g)

FACTORS FACTORS AFFECTING THE AFFECTING THE DAILY ENERGY DAILY ENERGY

REQUIREMENT OF REQUIREMENT OF THE BODYTHE BODY

AGEAGE Children & adolescent need more Children & adolescent need more

energy for growth compared to energy for growth compared to the adultsthe adults

They have a higher metabolic rate They have a higher metabolic rate to produce more energyto produce more energy

SEXSEX Males need more energy than Males need more energy than

females of the same age and females of the same age and body sizebody size

Generally, basal metabolic rate Generally, basal metabolic rate of male is higher than female of male is higher than female because they are more activebecause they are more active

BODY WEIGHTBODY WEIGHT The basal metabolic rate is proportional to The basal metabolic rate is proportional to

the surface area of the bodythe surface area of the body

Calculated from the height & weightCalculated from the height & weight

Hence individuals with big body weight need Hence individuals with big body weight need more energymore energy

OCCUPATIONOCCUPATION More energy is needed for the More energy is needed for the

muscular activities of the muscular activities of the person doing heavy physical person doing heavy physical work.work.

VITAMINSVITAMINS Important in the Important in the physiologyphysiology (the process that occur (the process that occur

in the organisms) & in the organisms) & metabolism metabolism (the biochemical (the biochemical reactions in the body cell) of the bodyreactions in the body cell) of the body

Two classes : Two classes : water-solublewater-soluble vitamins & vitamins & fat-solublefat-soluble vitaminsvitamins

Fat-solubleFat-soluble vitamins cannot be excreted out in vitamins cannot be excreted out in urine, stored in the bodyurine, stored in the body

Important for metabolic processes in animalsImportant for metabolic processes in animals Water-soluble vitamins cannot be stored in the Water-soluble vitamins cannot be stored in the

body, excrete through urinebody, excrete through urine Vitamins B & CVitamins B & C in plants, animals & m/organisms in plants, animals & m/organisms

function as coenzymes.function as coenzymes.

Properties of VitaminsProperties of Vitamins Cannot be digested or broken down to Cannot be digested or broken down to

produce energyproduce energy Easily destroyed at high temperatures or Easily destroyed at high temperatures or

when exposed to ultraviolet rayswhen exposed to ultraviolet rays Needed in small quantities onlyNeeded in small quantities only Cannot be synthesised in our body Cannot be synthesised in our body

except D.except D. Easily oxidised by oxygen in the air, Easily oxidised by oxygen in the air,

especially vitamin Cespecially vitamin C Needed for chemical reactions in the Needed for chemical reactions in the

body as co-enzymesbody as co-enzymes

FAT-SOLUBLE VITAMINSFAT-SOLUBLE VITAMINSVitaminVitamin SourceSource FunctionsFunctions Effects of deficiencyEffects of deficiency

A A (retinol)(retinol)

Milk, tomatoes, Milk, tomatoes, carrots, fish carrots, fish

liver oilliver oil

For healthy epithelium, including For healthy epithelium, including the skinthe skinFor night visionFor night visionFor growthFor growth

Night-blindnessNight-blindnessXerophthalmia (cornea Xerophthalmia (cornea disorder)disorder)Stunted growthStunted growth

D D (calciferol)(calciferol)

Fish liver oils, Fish liver oils, cheese, butter, cheese, butter,

eggs, eggs, synthesised by synthesised by

skinskin

Needed for absorption of calcium Needed for absorption of calcium and phosphorus in the intestinesand phosphorus in the intestinesHelps to build strong bones & Helps to build strong bones & healthy teethhealthy teeth

Rickets (weak bones)Rickets (weak bones)Osteomalasia in adultsOsteomalasia in adultsDental caries/ tooth Dental caries/ tooth decaydecay

E E (tocopherol)(tocopherol)

Wheat germ, Wheat germ, green green

vegetables, vegetables, palm oil, palm oil, mustard, mustard, cabbagecabbage

As antioxidantAs antioxidantPrevents sterility in animalsPrevents sterility in animalsMaintains the function of the Maintains the function of the reproductive systemreproductive systemPreserves healthy muscular Preserves healthy muscular system, nervous system & blood system, nervous system & blood circulatory systemcirculatory system

Deterioration of Deterioration of muscles & degeneration muscles & degeneration of nervesof nervesinfertilityinfertility

K K (naphtha-(naphtha-quinone)quinone)

Liver, Liver, tomatoes, tomatoes,

green vege, green vege, cabbagecabbage

Helps in blood clottingHelps in blood clotting AnaemiaAnaemiaSlow blood-clotting/ Slow blood-clotting/ extensive bleedingextensive bleeding

WATER-SOLUBLE VITAMINSWATER-SOLUBLE VITAMINSVitaminVitamin SourceSource FunctionsFunctions Effects of deficiencyEffects of deficiency

BB11 (thiamine)(thiamine)

Liver, yeast, Liver, yeast, meat, cereals, meat, cereals, beans, peas, beans, peas, green vegegreen vege

As a co-enzyme in As a co-enzyme in carbohydrate metabolismscarbohydrate metabolismsNeeded in cellular respirationNeeded in cellular respirationFor growthFor growthFor healthy nervous systemFor healthy nervous system

Beri-beri (fatigue, Beri-beri (fatigue, weakness & muscular weakness & muscular cramps)cramps)Disorder of the nervous Disorder of the nervous systemsystem

BB22 (riboflavin)(riboflavin)

Yeast, liver, Yeast, liver, milk, whole milk, whole

grains, eggs, grains, eggs, vegetablesvegetables

Needed in cellular respirationNeeded in cellular respirationFor growthFor growthFor healthy nervous systemFor healthy nervous system

Peeling of skin around Peeling of skin around the nose, ears & mouththe nose, ears & mouthSwollen tongueSwollen tongueStunted growthStunted growth

BB33 (niacin)(niacin)

Yeast, liver, Yeast, liver, cereals, eggs, cereals, eggs,

vegetablesvegetables

Needed in cellular respirationNeeded in cellular respirationFor healthy nervous system, For healthy nervous system, skin and intestineskin and intestine

Pellagra (inflammation Pellagra (inflammation of skin, diarrhoea & of skin, diarrhoea & mental disturbances)mental disturbances)

BB55 (pantothen(pantothen

ic acid)ic acid)

Eggs, meat, Eggs, meat, liver, yeast, liver, yeast, wheat germ, wheat germ,

fresh fresh vegetablesvegetables

Needed in cellular respirationNeeded in cellular respirationFor healthy nervous systemFor healthy nervous systemFor the formation of antibodiesFor the formation of antibodies

Stunted growthStunted growthDermatitisDermatitisGrey hairGrey hairDamage to adrenal Damage to adrenal glandsglands

WATER-SOLUBLE VITAMINSWATER-SOLUBLE VITAMINS

VitaminVitamin SourceSource FunctionsFunctions Effects of deficiencyEffects of deficiency

BB66 (pyridoxine(pyridoxine

))

Liver, eggs, Liver, eggs, meat, cereals, meat, cereals, beans, nuts, beans, nuts,

milkmilk

For the synthesis of amino For the synthesis of amino acidacid

Stunted growthStunted growthAnaemiaAnaemiaLow resistance to Low resistance to infectioninfectionDiarrhoeaDiarrhoea

BB1212 (cobalamin(cobalamin

))

Milk, eggs, Milk, eggs, meat, liver, fish, meat, liver, fish,

cheesecheese

For the formation of red For the formation of red blood cellsblood cells

AnaemiaAnaemia

C C (ascorbic (ascorbic

acid)acid)

Citrus fruits & Citrus fruits & green green

vegetablesvegetables

For maintaining healthy For maintaining healthy blood vesselblood vesselFor healthy skin & efficient For healthy skin & efficient healing of woundshealing of woundsIncreases resistance to Increases resistance to infectionsinfections

Scurvy (bleeding Scurvy (bleeding gums, bruised skins, gums, bruised skins, swollen joints)swollen joints)

MINERALSMINERALS Inorganic substances that are present Inorganic substances that are present

in the form of ionsin the form of ions Required in small quantities to preserve Required in small quantities to preserve

healthy growth & maintenancehealthy growth & maintenance Do not provide energyDo not provide energy Lack of minerals can cause various Lack of minerals can cause various

diseasedisease Divided into two groups : Divided into two groups : macronutrientsmacronutrients (large quantities) (large quantities) micronutrientsmicronutrients (small quantities) (small quantities)

MACROMINERALSMACROMINERALSMineralMineral SourceSource FunctionsFunctions Effects of deficiencyEffects of deficiency

CalciumCalcium Milk, cheese, Milk, cheese, anchovies, anchovies,

cerealscereals

Form strong & healthy teeth & Form strong & healthy teeth & bonesbonesAssists in blood clottingAssists in blood clottingNecessary for muscle contraction Necessary for muscle contraction & transmission of nerve impulses& transmission of nerve impulses

RicketsRicketsOsteoporosisOsteoporosisProlonged bleedingProlonged bleeding

Magne-Magne-siumsium

Cereals, green Cereals, green vegetables, vegetables, milk, meatmilk, meat

Necessary for muscle contractionNecessary for muscle contractionNecessary for transmission of Necessary for transmission of nerve impulsesnerve impulsesAs a cofactors for various As a cofactors for various enzymesenzymes

Weak musclesWeak musclesConvulsion (Sawan)Convulsion (Sawan)

Phospho-Phospho-rusrus

Milk, meat, Milk, meat, Cereals, eggsCereals, eggs

Forms strong bones and teethForms strong bones and teethForm ATP in cell respirationForm ATP in cell respiration

Brittleness of bonesBrittleness of bonesTooth decayTooth decay

SodiumSodium Table salt, Table salt, meat, eggs, meat, eggs,

milkmilk

Maintains the balance of water in Maintains the balance of water in the bodythe bodyMaintains the osmotic pressure in Maintains the osmotic pressure in the bodythe bodyNeeded for transmission of nerve Needed for transmission of nerve impulsesimpulses

Muscular crampsMuscular cramps

MACROMINERALSMACROMINERALSMineralMineral SourceSource FunctionsFunctions Effects of deficiencyEffects of deficiency

PotassiuPotassiumm

Milk, meat, Milk, meat, bananas, green bananas, green

vegetablesvegetables

For transmission of nerve For transmission of nerve impulsesimpulsesFor muscle contractionFor muscle contraction

Disorder in the nervous Disorder in the nervous systemsystem

MICROMINERALSMICROMINERALS

MineralMineral SourceSource FunctionsFunctions Effects of deficiencyEffects of deficiency

IodineIodine Prawns, Prawns, cockles, cockles, seafood, seafood, seaweedseaweed

Produces thyroxine hormoneProduces thyroxine hormone GoitreGoitreCretinism in childrenCretinism in children

IronIron Liver, spinach, Liver, spinach, nuts, egg yolknuts, egg yolk

Forms haemoglobinForms haemoglobin AnaemiaAnaemia

FluorineFluorine Drinking water, Drinking water, tea, vegetablestea, vegetables

Harden enamel of teeth, bonesHarden enamel of teeth, bones Dental cariesDental caries

ROUGHAGEROUGHAGE Dietary fibre in the diet that Dietary fibre in the diet that cannot be cannot be

digesteddigested Made up of Made up of cellulosecellulose (cell wall of plant (cell wall of plant

cells)cells) Sources : Sources : cereals, fruits, nuts & vegetablescereals, fruits, nuts & vegetables Functions :Functions :

1.1. Stimulate peristalsisStimulate peristalsis in alimentary canal & prevent constipation in alimentary canal & prevent constipation2.2. Helps to Helps to avoid from feeling hungryavoid from feeling hungry frequently frequently3.3. Soluble fibre from vegetables & fruits can help to Soluble fibre from vegetables & fruits can help to reduce reduce

cholesterolcholesterol levels in the blood levels in the blood

Deficiency : can Deficiency : can cause constipation cause constipation and and other disorders of the large intestineother disorders of the large intestine

Makes up Makes up about 70% of the total body about 70% of the total body weightweight

Found in all natural foodFound in all natural food Sources : fruits, vegetables, milk, soup Sources : fruits, vegetables, milk, soup

& drinking water& drinking water A large amount of water is lost through A large amount of water is lost through

urine, sweat & faeces urine, sweat & faeces must be must be replacedreplaced

Need to drink Need to drink 2 litres a day2 litres a day (8 glasses) (8 glasses)

WATERWATER

FUNCTIONS OF WATERFUNCTIONS OF WATER

1.1. As a solvent for all organic compounds & As a solvent for all organic compounds & minerals in the bodyminerals in the body

2.2. As a medium for chemical reactions in the As a medium for chemical reactions in the bodybody

3.3. As a medium of transportAs a medium of transport

4.4. For excretion of waste productsFor excretion of waste products

5.5. Controls & maintains body temperatureControls & maintains body temperature

6.6. As a lubricant to reducing friction between As a lubricant to reducing friction between bones in jointsbones in joints

7.7. Determine the osmotic concentration of Determine the osmotic concentration of blood and tissue fluid.blood and tissue fluid.

APPROPRIATE DIET MENU APPROPRIATE DIET MENU FOR TARGET GROUPFOR TARGET GROUP

Pregnant womenPregnant women Adequate nutrients are Adequate nutrients are

needed for her own self & needed for her own self & the foetus in the wombthe foetus in the womb

More calcium & More calcium & phosphorusphosphorus are needed to are needed to form strong bones & teeth form strong bones & teeth for the babyfor the baby

More ironMore iron – to build red – to build red blood cells to prevent blood cells to prevent anaemiaanaemia

AvoidedAvoided nicotine, caffeine nicotine, caffeine & alcohol& alcohol

InfantsInfants Rapid growth – need Rapid growth – need more more

proteinprotein More More calcium & calcium &

phosphorusphosphorus Mother’s milk contain all Mother’s milk contain all

the nutrientsthe nutrients & antibodies & antibodies

APPROPRIATE DIET MENU FOR TARGET GROUPAPPROPRIATE DIET MENU FOR TARGET GROUP

ChildrenChildren Have slower growth rate Have slower growth rate

compared to babiescompared to babies Need Need more proteinmore protein for growth, for growth,

should be more than their body should be more than their body mass (eg.: 1.2 g per kg for 8 mass (eg.: 1.2 g per kg for 8 year-old child)year-old child)

Need Need more carbohydrates & fatsmore carbohydrates & fats to supply energy because very to supply energy because very activeactive

Vitamins especially Vitamins especially vitamin Dvitamin D Minerals (iodineMinerals (iodine) to produce ) to produce

thyroxine hormone – for thyroxine hormone – for physical & mental developmentphysical & mental development

More calcium & phosphorusMore calcium & phosphorus

TeenagersTeenagers Between the ages 12-19Between the ages 12-19 Grow very fastGrow very fast For girls, puberty begins at 12 For girls, puberty begins at 12

years years rapid growth. For boys, rapid growth. For boys, begins at 14 years begins at 14 years rapid rapid growthgrowth

Need Need a lot of proteina lot of protein to build new to build new protoplasm as well as protoplasm as well as calcium & calcium & phosphorusphosphorus

Very active, need more energy Very active, need more energy need need more carbohydratesmore carbohydrates

Female teenagers Female teenagers need food rich need food rich in ironin iron (18 mg a day) compared to (18 mg a day) compared to male (10 mg a day). They lose male (10 mg a day). They lose blood during menstruation each blood during menstruation each month, needed to form month, needed to form haemoglobin in erythrocytes & to haemoglobin in erythrocytes & to prevent anaemiaprevent anaemia

APPROPRIATE DIET MENU FOR TARGET GROUPAPPROPRIATE DIET MENU FOR TARGET GROUP

AthletesAthletes Include Include more more

carbohydratescarbohydrates to supply to supply enough energy to carry enough energy to carry out the vigorous activities out the vigorous activities in sportsin sports

More More proteinprotein to build new to build new tissues to replace tissues tissues to replace tissues that are dead or damagedthat are dead or damaged

Calcium, sodium & Calcium, sodium & potassiumpotassium are also are also needed to strengthen the needed to strengthen the bones & to prevent bones & to prevent muscular crampsmuscular cramps

People with specific People with specific diseasesdiseases

Such as Such as osteoporosiosteoporosis s need need more calcium & more calcium & phosphorus, vitamin Dphosphorus, vitamin D

APPROPRIATE DIET MENU FOR TARGET GROUPAPPROPRIATE DIET MENU FOR TARGET GROUP

Age relatedAge related 55 years & above55 years & above undergo undergo

the process of aging & slow the process of aging & slow growthgrowth

Lose their appetite, less activeLose their appetite, less active Their diet should be rich in Their diet should be rich in

protein, vitamins & mineralsprotein, vitamins & minerals to to maintain good health & to repair maintain good health & to repair tissuestissues

Have weaker & more brittles Have weaker & more brittles bones, bones, need more calcium & need more calcium & phosphorusphosphorus

Less active, need Less active, need less less carbohydrates & fatscarbohydrates & fats

Avoid food contains a lot of fats, Avoid food contains a lot of fats, sugar & salt sugar & salt heart diseases, heart diseases, diabetes mellitusdiabetes mellitus & high blood & high blood pressurepressure

Lot of vegetables & fresh fruitsLot of vegetables & fresh fruits to replenish water in their bodyto replenish water in their body

VegetariansVegetarians Has to Has to consist of all types consist of all types

of food nutrientof food nutrient that are that are obtained from only plantsobtained from only plants