AND THE EARTH HATH HE

APPOINTED FOR HIS CREATURES.

WHEREIN ARE FRUIT AND
SHEATHED PALM TREES.HUSKED
GRAIN AND SCENTED HERB. WHICH
IS IT OF THE FAVOURS OF YOUR
LORD THAT YE DENY?
Al Rehman (Al Quran)
NUTRITION
 LECTURE CONTENTS
• BALANCED DIET
• DRIs OR DIETARY REFERENCE INTAKES
• ACCEPTABLE MACRONUTRIENT DISTRIBUTION
RANGES
• MAJOR FOOD GROUPS
• BEVERAGES
 BALANCED DIET

• “A balanced diet is one that contains all the

five types of dietary ingredients, i.e. proteins,
fats, carbohydrates, vitamins and minerals in
amounts sufficient for the particular individual
depending upon his age, sex etc.”
Those who, when they
spend are not extravagant
and not niggardly, but hold
a just (balance) between
these two (extremes).
67- Al-Furqân Al Quran
DRIs OR DIETARY REFERENCE INTAKES

The DRIs consist of four dietary reference

standards for the intake of nutrients for
specific age groups, physiologic states and
gender.

1. EAR Estimated Average Requirement

2. RDA Recommended Dietary Allowance
3. AI Adequate Intake
4. UL Tolerable Upper Intake Level
• The DRIs consist of four dietary reference standards for the
intake of nutrients designated for specific age groups,
physiologic states and gender.
• EAR is the average daily nutrient intake estimated to meet the
requirement of one half of healthy individuals in a particular
life stage and gender group.
• RDA is the average daily dietary intake level that is sufficient to
meet the nutrient requirements of nearly all (97-98%)
individuals in a life stage and gender group. It is not the
minimal requirement for healthy individuals, rather it is
intentionally set to provide a margin of safety for most
individuals.
• AI is set if sufficient scientific evidence is not available to
calculate RDA or EAR. It is based on estimates of nutrient intake
by a group of apparently healthy people that are assumed to
be adequate. For example estimate of daily mean nutrient
intake supplied by human milk for healthy full term infants who
are exclusively breast fed gives AI for young infants.
• UL is the highest average daily nutrient iintake level that is
likely to pose no risk of adverse health effects to almost all
individuals in the general population. It is not intended to be a
recommended level of intake, it is useful because of the
increased availability of fortified foods and increased use of
dietary supplements.
 DRIs OR DIETARY REFERENCE INTAKES
• EAR Estimated Average Requirement
– Intake at which the risk of inadequacy is 50%
– EAR is the average daily nutrient intake estimated to meet the
requirement of one half of healthy individuals in a particular life
stage and gender group.
• RDA Recommended Dietary Allowance
– Intake at which the risk of inadequacy is 2-3%
– RDA is the average daily dietary intake level that is sufficient to
meet the nutrient requirements of nearly all (97-98%) individuals
in a life stage and gender group. It is not the minimal requirement
for healthy individuals, rather it is intentionally set to provide a
margin of safety for most individuals.
 DRIs OR DIETARY REFERENCE INTAKES
• AI Adequate Intake
– Estimate of nutrient intake of healthy people.
– AI is set if sufficient scientific evidence is not available to
calculate RDA or EAR. It is based on estimates of nutrient
intake by a group of apparently healthy people that is
assumed to be adequate.
• UL Tolerable Upper Intake Level
– At an intake above UL the risk of adverse effects increases.
– UL is the highest average daily nutrient intake level that is
likely to pose no risk of adverse health effects to almost all
individuals in the general population. It is not intended to be
a recommended level of intake, it is useful because of the
increased availability of fortified foods and increased use of
dietary supplements.
 COMPARISON OF COMPONENTS OF DRIs

1.0 1.0

Risk of adverse effects

Risk of inadequacy

0.5 0.5
AI

EAR RDA UL 0
0

OBSERVED LEVEL OF NUTRIENT INTAKE

 ACCEPTABLE MACRONUTRIENT
DISTRIBUTION RANGES
• AMDR
• “A range of intakes for a particular
macronutrient that is associated with reduced
risk of chronic disease, while providing
adequate amounts of essential nutrients.”

As very high fat diet is associated with weight gain

Very high intake of saturated fats can raise the plasma LDL concentration and risk of CHD
Conversly very high carbohydrate diet is associated with reduction in plasma HDL, increase in
plasma TAG and increased risk of CHD
 AMDR
Acceptable macronutrient distribution ranges

Macronutrients
Carb
Fat
Prot

10-35%
Prot 21.43% Pies show Sums of Range

45-65%
Carb 52.38%

20-35%
Fat 26.19%
 MAJOR FOOD GROUPS

Bread group Vegetable group Fruit group Milk group Meat group
• Bread group includes grains, starchy vegetables
and beans. These are cheap sources of calories
and protein, iron and B vitamins.
• Vegetable group: source of beta carotene, other
vitamins and minerals.
• Fruit group: rich in water soluble vitamins.
Tomatoes and citrus fruit are rich in vitamin c
• Milk group: include milk and milk products other
than butter. Good source of high quality protein,
calcium and riboflavin.
• Meat group: includes meat, poultry, fish, eggs, dry
beans and nuts. Rich in protein and B vitamins.
Eggs are especially rich in vitamin A. Fish is rich in
n-3 polyunsaturated FA, which give protection
against IHD.
 MAJOR FOOD GROUPS
1. Bread group includes grains, starchy vegetables and
beans. These are cheap sources of calories and protein,
iron and B vitamins.
2. Vegetable group: source of beta carotene, other
vitamins and minerals.
3. Fruit group: rich in water soluble vitamins. Tomatoes
and citrus fruit are rich in vitamin c
4. Milk group: include milk and milk products other than
butter. Good source of high quality protein, calcium
and riboflavin.
5. Meat group: includes meat, poultry, fish, eggs, dry
beans and nuts. Rich in protein and B vitamins. Eggs
are especially rich in vitamin A. Fish is rich in n-3
polyunsaturated FA, which give protection against IHD.
 PROTEINS
• IMPORTANCE OF PROTEIN
IN DIET
• PROTEIN TURNOVER
• NITROGEN BALANCE
• NUTRITIONALLY ESSENTIAL
AMINO ACIDS
• PROTEIN QUALITY
• REQUIREMENT OF PROTEIN
IN DIET
 MEMBRANE PROTEINS CONTRACTILE PROTEINS

PURINES STRUCTURAL
PYRIMIDINES TRANSPORT PROTEINS PROTEINS

IMPORTANCE OF PROTEIN IN
DIET
ENZYMES
CREATINE
CH3
H2C=CH
CH=CH2
CH3
N N
NEUROTRANSMITTERS
Fe

N N
PLASMA PROTEINS CH3 CH3
-OOC-CH2-CH2 CH2-CH2-COO-
 PROTEIN TURNOVER
• Results from simultaneous synthesis and
degradation of protein molecules
• 300-400g each day
• In healthy adults the total amount of protein in
the body remains constant, because the rate of
protein synthesis is just sufficient to replace the
protein that is degraded.
Short lived proteins
Regulatory proteins, misfolded proteins
Long lived proteins
 AMINO
400 g
ACID
100 g
POOL
BODY PROTEIN DIET NONESSENTIAL
BREAKDOWN AA SYNTHESIS

TISSUE PROTEIN SYNTHESIS OF:

SYNTHESIS Porphyrins
Creatine
400 g Neurotransmitters
Purines
100 g
Pyrimidines
Other N containing
compounds

GLUCOSE KETONE BODIES

CO2
GLYCOGEN FATTY ACIDS
STEROIDS
Aminoacids released by hydrolysis
of dietary or tissue protein, or
synthesized de novo, mix with
other free amino acids distributed
thru out the body. Collectively they
constitute the amino acid pool. The
aa pool containing about 100g of
aa, is small in comparison with the
amount of protein in the body,
(about 12kg in a 70kg man). If the
only fate of the aa pool were to be
used to resynthesize body proteins,
adults would not have a significant
need for additional dietary protein
. However, only about 75% of aa obtained
thru hydrolysis of body protein, are
recaptured thru the biosynthesis of new
tissue protein. The remainder are
metabolized or serve as precursors for
the compounds shown in this slide. In
well fed individuals, this metabolic loss of
aa is compensated for by dietary protein
which contributes to aa pool
 NITROGEN BALANCE
• “The difference between intake and output of
nitrogenous compounds is known as N
balance”

• N is 16% of most proteins

• Output of N from the body
– Urea, undigested (feces), sweat, shed skin
3 STATES NITROGEN BALANCE
ESSENTIAL AMINO ACIDS

V LIT TH LAMP
 PROTEIN QUALITY
• “The quality of a protein is a measure of its
ability to provide the essential amino acids
required for tissue maintenance.”

• PDCAAS

Protein digestibility corrected amino acid scoring is the standard for evaluating
protein quality. It is based on the profile of the essential amino acids and the
digestibility of the protein. The highest possible score is 1.00. PDCAAS provides a
method to balance intakes of poorer quality proteins by vegetarians and others who
consume limited quantities of high quality proteins.
 PROTEIN QUALITY

Proteins from wheat, corn, rice and beans have a lower quality than do animal proteins.
However proteins from different plant sources may be combined in such a way that the result
is equivalent in nutritional value to animal protein.
• Protein digestibility corrected amino acid
scoring is the standard for evaluating protein
quality. It is based on the profile of the
essential amino acids and the digestibility of
the protein. The highest possible score is 1.00.
PDCAAS provides a method to balance intakes
of poorer quality proteins by vegetarians and
others who consume limited quantities of high
quality proteins.
 PROTEIN QUALITY

NPU = grams of protein digested and assimilated

grams of protein taken in diet

Net protein utilization

 PROTEIN QUALITY

P.E.R =grams of weight gain

grams of protein taken

In a specified time period

Protein efficiency ratio

 PROTEIN QUALITY
• “The content of essential
amino acids of a protein is
matched with that of egg
protein which is used as a
reference standard, and has
been assigned a chemical
score of 100.”
• PROTEIN QUALITY
– All essential amino acids
– Optimal proportion
– Easily digestible
PROTEIN QUALITY
 PROTEIN QUALITY

WHEAT KIDNEY BEANS

(lysine deficient – methionine rich) (lysine rich – methionine deficient)

Proteins from wheat, corn, rice and beans have a lower quality than do animal
proteins. However proteins from different plant sources may be combined in such
a way that the result is equivalent in nutritional value to animal protein.
PROTEIN QUALITY

WHEAT + KIDNEY BEANS

(lysine rich– methionine rich)
 REQUIREMENT OF PROTEIN
RDA for protein of mixed biologic value = 0.8g/kg body
wt/day OR 56g/day for a 70kg individual. People who
exercise strenuously on regular basis require extra protein
to maintain muscle mass, for example 1g/kg body wt/day is
recommended for athletes. Pregnant or lactatating women
require additional 30g/day.
The dietary requirement of the protein is influenced by the
carbohydrate content of the diet, when CHO intake is low
aa are deaminated to provide carbon skeletons for synthesis
of glucose that is needed as fuel for CNS.
Carbohydrates have a protein sparing effect, it allows aa to
be used for repair and maintenance of tissue protein rather
than for gluconeogenesis.
REQUIREMENT OF PROTEIN

2g/kg/day

PREGNANCY 1g/kg/day
LACTATION

Additional 30g/day
 CARBOHYDRATES
• IMPORTANCE OF
CARBOHYDRATES IN DIET
• REQUIREMENTS FOR
CARBOHYDRATE
• GLYCEMIC INDEX OF FOOD
• IMPORTANCE OF DIETARY
FIBER
• SACHAARINS
 O
O

IMPORTANCE OF
CARBOHYDRATES IN DIET
PROTEIN SPARING ATP

GLYCOSYLATION OF PROTEINS

LIVER AND MUSCLE GLYCOGEN

REQUIREMENTS FOR CARBOHYDRATES
• Not essential
• Absence leads to:
– Ketone body production
– Degradation of body protein
• RDA
– 130g/day
– 45-65% of total calories
 GLYCEMIC INDEX OF FOOD
• “Glycemic index is the area under the blood
glucose curves seen after ingestion of a meal
with carbohydrate rich food, compared with
the area under the blood glucose curve
observed after a meal consisting of the same
amount of carbohydrate in the form of glucose
or white bread.”
GLYCEMIC INDEX OF FOOD

140
High glycemic
index
Blood glucose
mg/dl

70

Low glycemic
index

0
0 40 80 120
Minutes after ingestion of food
 DIETARY FIBER
• Non starch polysaccharide NSP
• Total fiber
– Dietary fiber
– Functional fiber
• Soluble fiber
• Insoluble fiber
Dietary fiber is defined as nondigestible carbohydrates. Functional fiber is the isolated,
extracted, or synthetic fiber that has proven health benefits. Total fiber is sum of above
two. Soluble fiber forms a viscous gel when mixed with a liquid. Insoluble fiber passes
thru the digestive tract largely intact. Fiber provides little energy but has several beneficial
effects.Lignin is not a polysaccharide but is included in dietary fiber, it is a complex
polymer of phenylpropanoid subunits.
Dietary fiber “Nondigestible carbohydrates and lignin present in plants.”
Functional fiber “Isolated, extracted, or synthetic fiber that has proven health benefits.”
Soluble fiber “fibers that form a viscous gel when mixed with a liquid”
Insoluble fiber “passes thru the digestive tract largely intact”
 FIBER ----Health benefits
• Delays gastric emptying and generates a
sensation of fullness.
• Reduces postprandial blood glucose
concentration
• Reduces constipation, hemorrhoid formation by
softening the stool.
• Increases bowel motility
• Decreases absorption and increases fecal loss of
cholesterol
 NON-NUTRITIVE SWEETENERS
• Saccharin
• Aspartame
• Acesulfame K
Saccharin dates back to the 1900s and became widely used in the 1950s. There are however
health concerns regarding the use of Saccharins in that it may increase the potency of cancer
causing chemicals and could potentially cause harm to a fetus. As always, proceed with caution
until these concerns have been resolved.
Avoid Aspartame, a sugar substitute often used in drinks. The main producer, Neutrasweet, do
however indicate that it's not very well suited to baking as it looses its sweetness when
exposed to heat for long periods. However one does assume that it could be used in cold low
carb desserts.
For baking in low carb desserts Sucralose is probably the best choice. Sucralose is a derivative
of sugar and in terms of sweet taste, it can be substituted for common sugar without problem
or need for converting quantities and measurements. Sucralose is currently marketed under
the name of Splenda. It is great for low carb desserts and diets as it only contains 0.9g of
carbohydrates. That's over 4 times less that a tsp of normal sugar. As Sucralose is a synthetic
chemical, it is still largely unknown if any side effects exist and as such, its use should be used
in moderation.
 BEVERAGES
• An ideal drink?

•Cola, soft drinks, including commercial fruit juices,

contain unnecessarily large amounts of sugar, caffeine,
and phosphoric acid in some. Harm teeth and kidneys.
These drinks are hypertonic, therefore poor in
satisfying thirst.
•Tea and coffee contain caffeine, excessive intake can
cause fatigue, irritability, insomnia and tachycardia.
They also cause dehydration.
•Alcohol in excess is toxic to hepatocytes, depresses
cerebral activity.
•Lassi (highly diluted skimmed milk) supplies salt,
water, proteins and some water soluble vitamins and
minerals.
•Lemonade, good drink for summer months, provides
vitamin C, salt and water.
 LIPIDS
• IMPORTANCE OF LIPIDS IN
DIET
• DIETARY FATS AND PLASMA
LIPIDS
• ESSENTIAL FATTY ACIDS
• PLASMA CHOLESTEROL
LEVEL AND ITS
IMPORTANCE
• TRANS FATTY ACIDS
• WHAT IS PEROXIDATION OF
PUFA?
IMPORTANCE OF LIPIDS IN DIET

ATP VITAMINS
STEROID HORMONES
Adipose
tissue
PGs LDL

HDL
 n-6 OR Ω6 FATTY ACIDS
• Vegetable oils
– Nuts, olives, soybeans,
cottonseed, sesame and
corn oil
• Lower plasma LDLs
• Lower plasma HDLs

The powerful benefits of lowering LDLs are only partially offset because of the decreased HDLs.
Also a tree springing out of
Mount Sinai, which produces
oil, and relish for those who
use it for food.

20- al Mûminûn Al Quran

 n-3 OR Ω3 FATTY ACIDS
• Plants and fish oils
– DHA (Docosahexaenoic acid)
and EPA(Eicosapentaenoic
acid)
• Reduce risk of
cardiovascular mortality
– Little effect on HDL and LDL
– Supress cardiac arrythmias
– Reduce serum TAG
– Decrease tendency to
thrombosis
It is He Who has made the
sea subject, that ye may
eat thereof flesh that is
fresh and tender…..
14- An Nahl Al Quran
 IMPORTANCE OF Ω3 FAs
Ω6 FAMILY OF FATTY ACIDS AND THEIR PRODUCTS

PLATELET
AGGREGATION

INHIBIT
AGGREGATION
 IMPORTANCE OF Ω3 FAs
Ω3 FAMILY OF FATTY ACIDS AND THEIR PRODUCTS

WEAK PLATELET
AGGREGATION

STONGLY INHIBIT
AGGREGATION
 PLASMA CHOLESTEROL LEVEL AND ITS
IMPORTANCE
• Source
– Endogenous biosynthesis
– Diet (animal products)
• Transport
– Lipoproteins
– LDL and CHD
• Smoking, obesity, sedentary lifestyle, TAG
– HDL
• Effect of dietary cholesterol on plasma cholesterol
– Amount and types of FA (diet induced changes10-20%)
• Effect of Statin drugs on plasma cholesterol
– Decrease plasma cholesterol by 30-40%
 TRANS FATTY ACIDS
• Classified as unsaturated but behave as
saturated
• Elevate LDLs
• Source
– Not in plants
– Small amounts in animals
– Manufacture of margarine
 PUFA and LIPID PEROXIDATION
• Chain reaction providing continuous supply of free
radicals that initiate further peroxidation.
• Effects
– Rancidity
– Tissue damage
• Inflammatory disease, cancer, atherosclerosis and aging
• Antioxidants
– Food additives
• Propyl gallate, butylated hydroxyanisole BHA etc
– Naturally occuring
• Water soluble and Lipid soluble
• Chain breaking and preventive

Vitamin C and urate (water sol) Vitamin E (lipid sol). Super oxide dismutase, urate, vit E
(chain breaking), catalase, glutathione peroxidase (preventive)
And in the earth are tracts (diverse though)
neighboring, and gardens of vines and
fields sown with corn and palm trees----
growing out of single roots or otherwise:
watered with the same water, yet some
of them We make more excellent than
others to eat. Behold, verily in these
things there are Signs for those who
understand.
4 - Ar Ra’d Al Quran
 NUTRITION

CALORIC REQUIREMENTS OF THE

BODY
 LECTURE CONTENTS
• ENERGY REQUIREMENT
• UNITS OF ENERGY
• CALCULATING ENERGY EXPENDITURE
• ENERGY CONTENT OF FOOD
• METABOLIC RATE
• ENERGY EXPENDITURE FOR VARIOUS ACTIVITIES
• ENERGY BALANCE
• DIETARY ADVICE IN VARIOUS DISORDERS
 ENERGY REQUIREMENT
• “Number of calories or kJ that must be
consumed per day to support growth and
maintenance.”
• Units of energy
– Calories
– Joules
– 1 watt = 1J/sec
 UNITS OF ENERGY
• KILOCALORIE
– “Amount of heat required to raise the
temperature of 1 kilogram of water by 1°C.”
• 1 kilocalorie = 1000 calories
• KILOJOULE
– A kilojoule is the energy required to lift a load of 1
kg by 1 meter.”
• 1kJ = 0.239kcal
• 1kcal =4.184kJ
 CALCULATING ENERGY
EXPENDITURE
thermometer

Combustion
chamber
(Pure O2)

Water jacket

Insulation
The energy content of the food is calculated from the heat released by the total
combustion of food in a calorimeter. It is expressed in kcal, or Cal.
 ENERGY CONTENT OF FOOD

Carbohydrate 4 kcal/g
4 kcal/g
Protein

9 kcal/g
Fat

7 kcal/g
Alcohol
 CALCULATING ENERGY EXPENDITURE
• Respiratory quotient
O
– “the number of CO2
molecules discharged
from the body per
number of oxygen RQ = 1.0
molecules consumed.”

– CO2/O2

RQ = 0.7
 RESPIRATORY QUOTIENT
• The biochemical events of CO2 production and O2
utilization are a direct result of the oxidation of various
fuels such as fat and glucose.
• Respiratory gases can be measured and analyzed quite
easily. These measurements can be used to calculate the
amount of CO2 produced and O2 used by the body over
any given period. RQ can provide remarkable insight into
the overall behavior of energy fuels in the body
• . RQ is different for different fuels, for example
RQ for the complete combustion of glucose is
1.0, and that for complete combustion of fat is
0.7. RQ studies can be performed to
determine the type of fuel consumed during
rest and exercise and in calculation of energy
expenditure.
 RESPIRATORY QUOTIENT
• METHODS TO DETERMINE RQ
– OPEN CIRCUIT METHOD
– CLOSED CIRCUIT METHOD
 RESPIRATORY QUOTIENT
Douglas bag
Mouth piece
Tube

Stop cork

Valve

Gas collection bag

The subject is made to breath in a douglas bag for a few minutes, then the volume of air breathed
is measured in a gas meter and the sample is analyzed for O2 and CO2 concentrations in Haldane
gas analysis apparatus. A known volume of gas sample is first treated with KOH solution.
 OPEN CIRCUIT METHOD TO DETERMINE RQ

HALDANE GAS ANALYSIS APPARATUS

KOH

CO2 is taken up by KOH resulting in corresponding decrease in the original volume of the gas
sample. From this the concentration of CO2 in the expired air is found out.
OPEN CIRCUIT METHOD TO DETERMINE RQ

HALDANE GAS ANALYSIS APPARATUS

KOH TAKES UP CO2

 OPEN CIRCUIT METHOD TO DETERMINE RQ

HALDANE GAS ANALYSIS APPARATUS

ALKALINE PYROGALLATE

Later the remaining gas is made to react with alkaline pyrogallate which absorbs O2. From
this the concentration of O2 in the expired air is found out. RQ is calculated by fomula.
OPEN CIRCUIT METHOD TO DETERMINE RQ

HALDANE GAS ANALYSIS APPARATUS

ALKALINE PYROGALLATE
TAKES UP O2

RQ = Vol of CO2 exhaled

Vol of O2 utilized
 RESPIRATORY QUOTIENT
Spirometer

YELLOW
INDICATOR COACH
INDICATOR

PISTON

Mouth piece
 CLOSED CIRCUIT METHOD TO DETERMINE
RQ

NaOH

A spirometer is filled with O2 for inhalation by the subject. The subject inhales from and then
exhales into the same apparatus. The expired gases are made to pass over a concentrated
solution of NaOH which absorbs all CO2 present in these gases.
 CLOSED CIRCUIT METHOD TO DETERMINE
RQ

NaOH takes up CO2

As the subject continues breathing from and into the spirometer, the amount of O2 in the
spirometer falls, resulting in a fall in the spirometer volume.
 CLOSED CIRCUIT METHOD TO DETERMINE
RQ

As the subject continues breathing from and into the spirometer, the amount of O2 in the
spirometer falls, resulting in a fall in the spirometer volume. The decrease in the volume is
automatically recorded on a calibrated paper which is wound on a drum, rotating at a prefixed
speed. This fall in the volume gives the volume of O2 consumed.
CLOSED CIRCUIT METHOD TO DETERMINE
RQ
• Determination of absorbed CO2

NaOH CO2
CLOSED CIRCUIT METHOD TO DETERMINE
RQ
• Determination of absorbed CO2

Na2CO3 H2SO4
CLOSED CIRCUIT METHOD TO DETERMINE
RQ
• Determination of absorbed CO2

Na2SO4 + H2O + CO2

CO2 is liberated from the absorbent by adding H2SO4 to it. These reactions will take
place
 CLOSED CIRCUIT METHOD TO DETERMINE
RQ
RQ = Vol of CO2 exhaled
Vol of O2 utilized

The CO2 released from the absorbent is made to enter the spirometer resulting in an increase in
the spirometer volume. This increase in the volume is automatically recorded on a calibrated
paper which is wound on a drum, rotating at a prefixed speed. This increase in the volume gives
the volume of CO2 exhaled by the subject. From the volume of O2 consumed and CO2
liberated, RQ can be calculated.
 METABOLIC RATE
• “It is the output of energy by a person which is
expressed as kcals/ m² body surface area/ hr”

The body obtains energy by the oxidation of food. The oxidation of food
results in production of heat. The energy output or the metabolic rate
of an individual may be found out by measuring his heat production
over a known period of time. There are 2 methods to determine the
metabolic rate of a person.
• Determination methods
– Direct calorimetry
– Indirect calorimetry
 DIRECT CALORIMETRY
• Principle is same as bomb calorimeter except
one difference

In bomb calorimeter spark is used to induce combustion of food and that O2 is present at
high P to facilitate combustion, whereas in direct calorimetry enzymes catalyze the
combustion of food, the combustion proceeds more slowly, and the temperature of the
subject does not increase much over the normal resting body temperature with the various
activities.
DIRECT CALORIMETRY the subject is placed in an insulated chamber. He is instructed to do
the type of activity for which the metabolic rate has to be measured. Water is allowed to
flow through the chamber at a certain rate and the heat lost by the subject is used to raise
the temperature of this water. The temperature of water on entering as well as on leaving
the chamber is noted. In this way , the heat given off by the subject during a known period
of time can be found out.
 DIRECT CALORIMETRY

A
B
S
O
R
B
E
N
T
 METABOLIC RATE
The subject also looses heat by evaporation of water from the skin and the respiratory tract.
These water vapors are taken up by a chemical absorbent and their mass measured at the end
of the experiment.
1 gram of evaporated water represents a loss of 0.58kcal, the total amount of heat lost by this
route can be found out from the mass of water vapors given off by the subject. The number of
kcal thus obtained is added to the amount of heat calculated from the rise in temperature of the
water flowing thru the chamber. The total number of kcal lost/ hr is calculated.
Metabolic rate is determined by the formula.

• DIRECT CALORIMETRY
–Metabolic rate = kcal/m²/hr
 INDIRECT CALORIMETRY
• DETERMINATION OF
– RQ
– RATE OF O2 UTILIZATION
• USE OF TABLE
– Kcal OF ENERGY LIBERATED/ LITER OF O2
CONSUMED AT SPECIFIC RQ FROM TABLE
• CALCULATION OF METABOLIC RATE
 ENERGY BALANCE

ENERGY ENERGY
INTAKE EXPENDITURE

Energy balance is the difference between energy intake and energy expenditure. Weight gain or
loss is a simple but accurate way of indicating differences in energy balance.
ENERGY BALANCE
 ENERGY EXPENDITURE FOR VARIOUS
ACTIVITIES
• BASAL METABOLIC RATE
– BMR is the rate of use of body’s energy stores. It is
determined while at rest after an overnight fast.
• RESTING METABOLIC RATE
– Measured under resting conditions within an hour or a few
hours of consuming a meal.
• SLEEPING ↓ by 10%
• STANDING FROM LYING POSITION 30%
• THERMIC EFFECT OF FOOD 5-10%
• PHYSICAL ACTIVITY
• AGING
BMR is the reference point in addressing the energy needs of an individual. The RMR is
somewhat higher than the BMR but is more variable.
 ENERGY REQUIREMENTS
Other

Physical activity •Sedentary 30-50% more than RMR

VARIES •Highly active 100% or more above
THERMIC EFFECT OF FOOD
RMR
ENERGY EXPENDITURE / DAY

5-10%
kcal

•Respiration
RMR •Blood flow
50-70% •Ion transport
•Maintenance of cellular integrity
ENERGY EXPENDITURE FOR
VARIOUS ACTIVITIES

Lying at rest 1.0 times BMR

ENERGY EXPENDITURE FOR
VARIOUS ACTIVITIES

Very light activity 1.5 times BMR

ENERGY EXPENDITURE FOR
VARIOUS ACTIVITIES

Light activity 2.5 times BMR

ENERGY EXPENDITURE FOR
VARIOUS ACTIVITIES

Moderate activity 5.0 times BMR

ENERGY EXPENDITURE FOR
VARIOUS ACTIVITIES

Heavy activity 7.0 times BMR

 CALORIC REQUIREMENT
• AGE
• WEIGHT
• SEX
• PHYSIOLOGICAL FACTORS
• LEVEL OF ACTIVITY
 ISSUES IN ENERGY NUTRITION
• Obesity
• Pregnancy and Lactation
• Thyroid
• Dietary advice in various metabolic disorders
– Diabetes mellitus
• Hypertension and diet
It is He Who brought you forth
from the wombs of your mothers
when ye knew nothing; and He
gave you hearing and sight and
intelligence and affections; that
ye may give thanks.
An Nahl Al Quran
 PREGNANCY
• Energy requirement
– by 14% Should consume 300-500kcal/day in
addition to basal requirement
• Changes in pregnancy
– BMR
– Gastrointestinal changes
– Hormonal changes
– Changes in the body fluid
– Altered renal function
 PREGNANCY
• Diet in pregnancy
– Need for calories, proteins, vitamins, minerals and water
• Total weight gain
– 11 kg
• Infant 3.3kg
• maternal fat stores 3.3kg (30,000 kcal of energy)
• Food utilized for
– Synthesis of new tissues
• Maternal and fetal
– Energy for increased biosynthetic activity
– Deposition of maternal fat
DIET IN PREGNANCY

MILK AND HIGH CALCIUM FOODS

PROTEIN FOODS

BREADS AND GRAINS

DIET IN PREGNANCY

FRUITS AND VEGETABLES

FATS AND OILS

IRON AND THIAMINE RICH FOODS

DIET IN PREGNANCY

FLUIDS

FIBER

VITAMINS AND MINERALS

DIET IN PREGNANCY

ALCOHOL/
SMOKING

OVER GRILLED, CHARRED

OR BLACKENED FOODS

PHOSPHORUS FROM SOFT DRINKS

 NEWBORN

• 0-0.5 yr
– 115 kcal/kg body weight/day
• 0.5-1 yr
– 105 kcal/kg body weight/day
 INFANT
• WEANING
– Fruit juice
– Mashed and whipped fruit and vegetables
– Egg yolk
– Cereals
• Importance of good nutrition in pregnancy and early
infancy
– Rapid growth
– Nervous system
– immunocompetence
And (remember) Job, when he
cried to his Lord “Truly distress
has seized me, but thou art the
Most Merciful of those who show
Mercy.”
83 – Al Anbiyāa Al Quran
 HYPERTENSION
STROKE

KIDNEY IMPAIRED
FAILURE VISION HEART
FAILURE
• Decrease sodium
• Increase potassium
• Watch the calories
• Maintain a reasonable weight
 HYPERTENSION
• Sodium
– RDA = 1500-2300mg/day
• Potassium
– Potassium rich foods
• Calcium
– DRI 1000mg/day
• Protein
– 20gm/day
 HYPERTENSION
• Fat
– Olive oil, canola oil
• Fluid
• Weight
HYPERTENSION
 DIABETES MELLITUS

NEUROPATHY
CARDIOVASCULAR
OBESITY DISEASE
HYPERCHOLESTROLEMIA

NEPHROPATHY
BP CATARACT

HYPERTENSION
 DIABETES MELLITUS
• PROTEINS
– 20-25%
• CARBOHYDRATES MILK

– 40%
• FIBER
• FATS
– 30-35%
• FRIUTS
• VEGETABLES
 NUTRITION

NUTRITIONAL DISORDERS
…… the Lord and Cherisher of the worlds,
Who created me and it is He Who guides
me. Who gives me food and drink. And
when I am ill, it is He who cures me. Who
will cause me to die, and then to live
(again). And Who, I hope, will forgive me
my faults on the Day of Judgment.
77-82 Ash-Shûarâa Al-Quran
 LECTURE CONTENTS

• DEFICIENCY OF ESSENTIAL FATTY ACIDS

• CORONARY ARTERY DISEASE
• SUCROSE AND DENTAL CARIES
• ANOREXIA NERVOSA
• BULIMIA NERVOSA
• PROTEIN ENERGY MALNUTRITION
• KWASHIORKOR
 DEFICIENCY OF ESSENTIAL FATTY ACIDS
• Triene/ tetraene ratio in plasma lipids
• DHA
– Development of brain and retina
– Supplied via placenta and milk
– Retinitis pigmentosa---
↓ DHA.
• Scaly dermatitis
• Hair loss
• Poor wound healing
 CORONARY ARTERY DISEASE
• Saturated fats
• Cholesterol
 SUCROSE AND DENTAL CARIES
• Cola and soft drinks
• Commercial fruit juices
• Candies / chocolates
• White bread
 ANOREXIA NERVOSA
• Anorexia nervosa is a psychiatric, eating
disorder characterized by low body weight
and body image distortion with an obsessive
fear of gaining weight.
 BULIMIA NERVOSA
• Bulimia nervosa is an eating disorder
characterized by recurrent binge eating,
followed by compensatory behaviors, referred
to as "purging".
 Protein-energy malnutrition
• Protein-energy malnutrition (or protein-calorie
malnutrition) refers to a form of malnutrition
where there is inadequate protein intake.
• Protein-energy malnutrition affects children the
most because they have less protein intake. The few
rare cases found in the developed world are almost
entirely found in small children as a result of
fad diets, or ignorance of the nutritional needs of
children, particularly in cases of milk allergy.[5]
 Protein-energy malnutrition
• Types include:[2]
• Kwashiorkor (protein malnutrition
predominant)
• Marasmus (deficiency in both calorie and
protein nutrition)
• Marasmic Kwashiorkor (marked protein
deficiency and marked calorie insufficiency
signs present, sometimes referred to as the
most severe form of malnutrition)
PRECIPITATING FACTORS

· LACK OF FOOD (famine, poverty)

· INADEQUATE BREAST FEEDING
· WRONG CONCEPTS ABOUT NUTRITION
· DIARRHOEA & MALABSORPTION
· INFECTIONS (worms, measles, T.B)
 KWASHIORKOR
• Cecilly Williams, a British nurse, had
introduced the word Kwashiorkor to the
medical literature in 1933. The word is taken
from the Ga language in Ghana & used to
describe the sickness of weaning.
 ETIOLOGY

• Kwashiorkor can occur in infancy but its

maximal incidence is in the 2nd yr of life
following abrupt weaning.
• Kwashiorkor is not only dietary in origin.
Infective, psycho-socical, and cultural factors
are also operative.
 ETIOLOGY (2)
• Kwashiorkor is an example of lack of
physiological adaptation to unbalanced
deficiency where the body utilized proteins
and conserve S/C fat.
• One theory says Kwash is a result of liver insult
with hypoproteinemia and oedema. Food
toxins like aflatoxins have been suggested as
precipitating factors.
CONSTANT FEATURES OF KWASH

• OEDEMA

• PSYCHOMOTOR CHANGES

• GROWTH RETARDATION

• MUSCLE WASTING
USUALLY PRESENT SIGNS

• MOON FACE

• HAIR CHANGES

• SKIN DEPIGMENTATION

• ANAEMIA
OCCASIONALLY PRESENT SIGNS

• HEPATOMEGALY
• FLAKY PAINT DERMATITIS
• CARDIOMYOPATHY & FAILURE
• DEHYDRATION (Diarrh. & Vomiting)
• SIGNS OF VITAMIN DEFICIENCIES
• SIGNS OF INFECTIONS
 DD of Kwash Dermatitis

• Acrodermatitis Entropathica
• Scurvy
• Pellagra
• Dermatitis Herpitiformis
 MARASMUS
• The term marasmus is derived from the
Greek marasmos, which means wasting.
• Marasmus involves inadequate intake of
protein and calories and is characterized by
emaciation.
• Marasmus represents the end result of
starvation where both proteins and calories
are deficient.
 MARASMUS/2

• Marasmus represents an adaptive response

to starvation, whereas kwashiorkor
represents a maladaptive response to
starvation
• In Marasmus the body utilizes all fat stores
before using muscles.
 EPIDEMIOLOGY & ETIOLOGY

• Seen most commonly in the first year of life

due to lack of breast feeding and the use of
dilute animal milk.
• Poverty and diarrhoea are the usual
precipitating factors
• Ignorance & poor maternal nutrition are also
contributory
Clinical Features of Marasmus

• Severe wasting of muscle & s/c fats

• Severe growth retardation
• Child looks older than his age
• No edema or hair changes
• Alert but miserable
• Hungry
• Diarrhoea & Dehydration
 Investigations for PEM
• Full blood counts
• Blood glucose profile
• Septic screening
• Stool & urine for parasites & germs
• Electrolytes, Ca, Ph & ALP, serum proteins
• CXR & Mantoux test
• Exclude HIV & malabsorption
 NON-ROUTINE TESTS

• Hair analysis
• Skin biopsy
• Urinary creatinine over proline ratio
• Measurement of trace elements levels, iron,
zinc & iodine
 Complications of P.E.M
• Hypoglycemia
• Hypothermia
• Hypokalemia
• Hyponatremia
• Heart failure
• Dehydration & shock
• Infections (bacterial, viral & thrush)
 TREATMENT

• Correction of water & electrolyte imbalance

• Treat infection & worm infestations
• Dietary support: 3-4 g protein & 200 Cal /kg body
wt/day + vitamins & minerals
• Prevention of hypothermia
• Counsel parents & plan future care including
immunization & diet supplements
 KEY POINT FEEDING

• Continue breast feeding

• Add frequent small feeds
• Use liquid diet
• Give vitamin A & folic acid on admission
• With diarrhea use lactose-free or soya bean
formula
 PROGNOSIS

• Kwash & Marasmus-Kwash have greater risk

of morbidity & mortality compared to
Marasmus and under weight
• Early detection & adequate treatment are
associated with good outcome
• Late ill-effects on IQ, behavior & cognitive
functions are doubtful and not proven
 PEM
• MARASMUS
KWASHIORKOR
– Deficiency of calories
proteins
– Earlier
2-3 yrs age
age
– “Disease of the deposed baby when the next one
is born.”
 PEM
• MARASMUS
KWASHIORKOR
– Edema
Gross wasting and growth retardation
– Not
Growth
associated
retardation
with to some extent
• Altered hair
– Associated with
• Dermatosis
Abnormal hair
• Anemia
Dermatosis
• Edema
Mild to moderate anemia
– Internal
• Poor organs
appetiteare small but do not exhibit morphological changes
• Apathyis good
– Appetite
• Fatty liver
• Atrophy of pancreas, salivary gland and intestine
 MARASMUS & KWASHIORKOR
• Serum and tissue proteins
• Amino acid metabolism
• Enzymes
• Carbohydrates and fat metabolism
• Minerals
• Hormones
 MALNUTRITION SPECTRUM
PROTEIN ENERGY MALNUTRITION
ENERGY ENERGY & PROTEIN PROTEIN

The fasting blood glucose is lowered both in K and M, while plasma insulin level is near
normal in K and reduced in marasmus. I/V GTT is impaired in K, but unaffected in M.
the mechanism of impairment of glucose tolerance which cannot be corrected by
administration of insulin, is not properly understood. Advanced cases of K are
intolerant to lactose because of deficiency of intestinal disaccharidases. The alterations
in serum lipids consist of a reduction in TG, cholesterol, and phospholipids, and a rise in
FFA. The fatty liver of K is due chiefly to the accumulation of TG. In M the plasma lipid
pattern tends to be normal except for the raised FFA
CARBOHYDRATES AND FAT METABOLISM

FASTING BLOOD GLUCOSE

INSULIN

IMPAIRED
I/V GTT RESISTANT TO INSULIN ADM

LACTOSE INTOLERANCE PRESENT

SERUM TAG, CHOLESTEROL, PL FATTY LIVER

FFA
 MINERALS

K
Fe DIARRHOEA
Cu
↓SIDEROPHILIN

FOLATE ↓CERULOPLASMIN

ANEMIA

There is a reduction in the serum K, Fe and Cu in kwashiorkor. The reduction in K can be

attributed to diarrhea. However tissue analysis reveals a fall in K and a concomitant fall in
nitrogen, which suggests loss of cells. The fall in the Fe and Cu may be due to decreased
synthesis of binding proteins like siderophilin and ceruloplasmin. Folate and Fe deficiency
is the cause of anemia in kwashiorkor.
 SERUM AND TISSUE PROTEINS

ALBUMIN
α2 GLOBULIN
β GLOBULINS
γ GLOBULINS PLASMA
PROTEINS
 SERUM AND TISSUE PROTEINS

ATROPHY OF
PANCREAS,
SALIVARY
PROTEINS GLAND AND
RNA INTESTINE
RIBOSOMES
CELLULAR AMINO
ACID POOL

Alterations in
mitochondria have also
been reported.
TROPICAL MALABSORPTION SYNDROME
(IRON, B12, XYLOSE)
STEATORRHOEA
 AMINO ACID METABOLISM

VALINE
PHENYLALANINE LEUCINE
ISOLEUCINE
TYROSINE
CITRULLINE
ARGININE
GABA

All amino acids are not uniformly affected, suggesting a differential modification of their
metabolism. In general there is a lowering of the essential amino acids, particularly the
branched ones. Incomplete metabolism of phenylalanine results in decreased levels of tyrosine.
 ENZYMES

TRANSAMINASES
ALKALINE SERUM AMYLASE
PHOSPHATASE LIPASE
PSEUDO CHOLINESTERASE
PANCREATIC ENZYMES
ARGININOSUCCINASE

Marked alterations have been reported in serum as well as tissue enzymes. Upon
treatment the level of these enzymes returns to normal.
 HORMONES

GROWTH HORMONE
CORTICOSTEROIDS

Both in marasmus and kwashiorkor there is increase in the level of GH and corticosteroids.
The raised GH levels can be attributed to hypoglycemia. However the normal diurnal
pattern of secretion of corticosteroids is lost.
ALTERATIONS IN PROTEIN METABOLISM

ATROPHY

ALTERED HEMODYNAMICS

OSTEOPOROSIS

CONCENTRATING
ABILITY
GFR
RPF
DECREASED IMMUNITY
LETS ATTACK
HIM

DIMINISHED PHAGOCYTOSIS
ATROPHY OF LYMPHOID TISSUE
↓ T CELL IMMUNITY
 EDEMA
DECREASED PLASMA
PROTEINS (ALBUMIN)

DECREASED PLASMA ELECTROLYTE

COLLOID OSMOTIC P IMBALANCE

DECREASED
RENAL AND
ANTIDIURETIC
CARDIAC
SUBSTANCES
EDEMA DYSFUNCTION
And in the earth are tracts (diverse though)
neighboring, and gardens of vines and
fields sown with corn and palm trees----
growing out of single roots or otherwise:
watered with the same water, yet some
of them We make more excellent than
others to eat. Behold, verily in these
things there are Signs for those who
understand.
4 - Ar Ra’d Al Quran
 NUTRITION

OBESITY AND STARVATION

Dr. Shazia Rashid

Assistant Professor
Biochemistry Dept. CMH LMC Lhr.
 LECTURE CONTENTS
• REGULATION OF FOOD INTAKE
• ANTHROPOMETRIC STUDIES
• BODY MASS INDEX
• OBESITY
• STARVATION
 REGULATION OF FOOD INTAKE

• Hunger center
– Lateral hypothalamic area
• Satiety center
– Ventromedial nucleus
 REGULATION OF FOOD INTAKE
• Hormones that decrease appetite
– Leptin
– Adiponectin
– Resistin
• Hormones that increase appetite
– Ghrelin
REGULATION OF FOOD INTAKE

Efferent signals

DECREASED APPETITE
INCREASED METABOLISM
REGULATION OF FOOD INTAKE

Efferent signals

INCREASED APPETITE
DECREASED METABOLISM
 REGULATION OF FOOD INTAKE

INSULIN LEPTIN
Acetyl CoA
Acetyl CoA Carboxylase
Malonyl CoA

CPT-I
Fatty acid Beta oxidation
 REGULATION OF FOOD INTAKE
LEPTIN
POMC GENE
expression
NEUROPEPTIDE Y
A potent appetite ALPHA MSH
stimulator
MCR-4

DECREASED DECREASED
APPETITE ADIPOSITY
REGULATION OF FOOD INTAKE

LEPTIN

SYMPATHETIC NERVOUS SYSTEM

TRH & TSH

INCREASED METABOLISM & THERMOGENESIS

 ANTHROPOMETRIC STUDIES
• Height and weight
• Waist hip ratio; is used to assess the type of obesity (android or gynoid).
• BMI; is a measure of the total body fat
• Skinfold measurements; Skinfold thickness is measured by pinching the skin and using
calipers to measure the layers of skin and subcutaneous fat. It is a fairly direct measure of
the subcutaneous fat at the location of the pinch, but the usual goal of the method is to gain
an indication of total body fat.
• Densitometry; involves under water weighing. By weighing the subject in air, and when
totally submerged in water, one can calculate the density of the subject’s entire body. Then a
formula is used to relate this density with total body fat.
• Ultrasound ; is used to determine the thickness of subcutaneous fat. The results are similar
but not identical to those obtained from skin fold measurements. Skin fold measurements
are difficult to acquire in very obese subjects and here US may be the preferred technique.
• Bioelectrical impedance ; Bioelectrical impedance involves connecting electrodes to the
hands and feet and passing a mild electrical current through the body. Most organs and
tissues conduct the electrical current, as they contain water and salts. However, the adipose
tissue contains only about 14% water, by weight, and does not readily conduct electricity.
The results give an indication of total body fat.
• Computed tomography; used to study subcutaneous and viceral fat.
• Serum albumin level
 BODY MASS INDEX
• “Body mass index (BMI) or Quetelet Index is a
statistical measure of the weight of a person
scaled according to height.”

Body Mass Index (BMI) = Weight (kg) / Height (m) ²

BMI distributions are commonly used in the scientific literature to describe weight for
stature. BMI has been considered as a gold standard for defining overweight and
obesity; it has been correlated with percentage body fat
BODY MASS INDEX
 OBESITY
Obesity is defined as an
excess accumulation of
body fat, and it is the
amount of this fat that
correlates with ill-health.”
OBESITY
White adipose tissue is colored white or yellow and has relatively
few nerves and blood vessels. Each fat cell contains a single large
droplet of triglycerides that is coated with a protein called perilipin.
The droplet is not surrounded by a bilayer of phospholipids, and thus
cannot be called a vesicle. White fat is used as a site for storing energy
for physical activity.
Brown fat contains relatively more nerves and blood vessels. Each
brown fat cell contains several small droplets of triglyceride, rather
than one large droplet. Brown fat is used only for heat production. It
occurs in all newborn mammels , including humans, apparently to
assure that they keep warm. Brown fat is absent in adult humans, but it
occurs in adult hibernating animals and in animals that are active in
cold weather such as rats. Brown fat does not respond much to a low
energy diet or to over eating. Brown fat cells have large number of
mitochondria. In the mitochondria of brown fat the flow of protons out
and back thru the mitochondrial membrane produces mainly heat. The
influx of protons thru the membrane occurs thru channels of a special
protein called thermogenin.
 OBESITY

Fat deposits may be classed as subcutaneous and visceral. Subcutaneous fat occurs as a more
or less continuous layer throughout the body. Women have more % body fat. Subcutaneous
fat is measured at four sites in the body. In contrast, visceral fat (deep fat) is distributed
similarly in human males and females. The visceral fat in the abdomen occurs in three areas
The anatomic distribution of body fat has a major influence on associated health risks.
Excess fat located in the central abdominal area of the body is called android or “apple
shaped” or upper body obesity. And is associated with a greater risk of hypertension,
insulin resistance, diabetes, dyslipidemia and coronary heart disease. In contrast, fat
distributed in the lower extremities around the hips or gluteal region is called gynoid or
“pear shaped” or lower body obesity. The pear shape is relatively benign health wise and
is commonly found in females.
 ANDROID AND GYNOID OBESITY

WHR< 0.8 ♀
WHR< 1.0 ♂
WHR > 0.8 ♀ subcutaneous fat
WHR > 1.0 ♂
Viceral fat

Measurement of waist hip ratio has proven to be useful in diagnosing these types of obesty.
The units of each measurement is in centimeters, while the ratio has no unit.
 ANDROID AND GYNOID OBESITY

Substances released from abdominal fat are absorbed via the portal vein and thus have
direct access to the liver. FA taken up by the liver may lead to insulin resistance (associated
with obesity), and increased synthesis of triacylglycerols, which are released as VLDL
 ANDROID AND GYNOID OBESITY

General
circulation

By contrast free fatty acids from gluteal fat enter the general circulation and have no preferential
action on hepatic metabolism.
BODY WEIGHT REGULATION

ENERGY ENERGY
INTAKE EXPENDITURE
 FACTORS CONTRIBUTING TO OBESITY
• Genetic
– Both parents obese → 70-80% chance
– Both parents lean → 9% chance
– Identical twins → same BMIs
– Complex polygenic disease
• Environmental
– Energy rich dense foods
– Sedentary lifestyle
 METABOLIC CHANGES IN OBESITY
• METABOLIC SYNDROME
– Glucose intolerance
– Insulin resistance
– Hyperinsulinemia
– Dyslipidemia (low HDL and elevated VLDL)
• DYSLIPIDEMIA
 REDUCING BODY WEIGHT
• Physical activity
• Caloric restriction
– One lb of adipose = 3500 kcal
• Pharmacological
– Sibutramine
– orlistat
• Surgical treatment
 STARVATION
• Yet when He removes
the distress from you,
behold! Some of you
turn to other gods to
join with their Lord---
54-An Nahl Al Quran
 ENERGY METABOLISM
• Availabilty of substrates
• Allosteric activation and inhibition of enzymes
• Covalent modification of enzymes
• Induction/ repression of enzyme synthesis
ENERGY METABOLISM

+
ENERGY METABOLISM

-
WELL FED STATE
WE ARE A HAPPY
FAMILY
 WELL FED STATE

•I’ll eat glucose and get acetyl CoA from it

• FA synthesis
• CAC cycle
•I’ll synthesize and store glycogen for rainy days
It is my •I’ll synthesize triglycerides
SYNTHESIS
TIME!
•I’ll synthesize VLDL from TAG
•I’ll replenish proteins
 WELL FED STATE

•I’ll have glucose and get G3P from it

•I’ll synthesize TAG and store it
•I’ll send HSL to bed, he needs rest
•I’ll put LL to work, it is his turn

We
work in LL
turns!

HSL
 WELL FED STATE
Hi!
•I’ll have glucose to eat
•I’ll store glycogen
•I’ll synthesize my proteins
WELL FED STATE
THANKS PALS!

•I can eat as much glucose as I like

 STARVATION
Don’t worry, we’ll save TOGETHER WE’LL
you STRIVE IN TIME OF
CRISES

CATABOLISM
PREVAILS, WE’VE
GOT TO SAVE
THE BRAIN.
I feel
feeble
STARVATION
SHARING & CARING IS OUR
MOTO

•I’ll give my glycogen for glucose

•I can make glucose → gluconeogenesis
•I’ll eat FA myself
•I’ll make ketone bodies from acetyl coA for
the others
STARVATION
Wake up son! We
are in crises

•I’ll give my triglyceride stores

HSL •Liver can have FA & glycerol
HSL
 STARVATION
I’ll sacrifice myself
by giving up my Thanks! for saving
protein my life

•Liver can use my proteins to

make glucose
•I’ll also give my glycogen
•I can eat FA and ketone bodies
they are yummy!
 STARVATION
Ketone bodies are
yummy!
•Thanks everybody for sacrificing your
fuels for providing me glucose
•I can also live on ketone bodies if
situation arises
SHARING AND CARING
TOGETHER WE SURVIVED THRU
CRISES!
They
care for
me!

LL HSL
 SKELETAL VS CARDIAC MUSCLE
• CARDIAC
SKELETAL
– O2 consumption
• Only
30% (rest)
Aerobic90%metaboilsm
(exer)
– • Anaerobic as well
Activity
– Activity
• Continuous
– • Intermittent
Fuel
– Fuel
• Glucose
• FFA
Rest
– FFAbodies
• Ketone , ketone bodies
– • Exercise
Energy store/ after meal
– Glucose,
• Negligable branched
amount of chain aa and lipid
glycogen
– Energy store
• glycogen