ENERGY ENERGY REQUIREMENTSREQUIREMENTS

THE NEED OF ENERGYTHE NEED OF ENERGY

Dr. Gilang Nurdjannah, dr. Dr. Gilang Nurdjannah, dr. Dipl.NutrDipl.Nutr

Department of NutritionDepartment of NutritionMedical Faculty, Padjadjaran UniversityMedical Faculty, Padjadjaran University

The The Calorie :Calorie :• The standard unit used to measured

energy• Used in nutrition as kilo calorie (large

calorie, written Calori (Cal)• Is thousand times greater than small

calorie (cal) used in chemistry or physics (Robinson, Lawler, Wilson, et all)

• 1 kilocalorie is the amont of heat required to raise the temperature of 1 kg water 10C (from 150C to 160C)

The vital process The vital process are :are :

• The functional activities of the various important organs such as the brain, heart, liver, kidneys, lungs (respiratory system).

• The secretory activities of the glands.• The peristaltic movements of gastrointestinal tract.• The oxidations of resting tissues.• The maintenance of muscular tone.

BEE (Basal Energy Expenditure) is energy expenditure/usage of energy in basal condition, is the ongoing activity while the body rest, i.e heart beat, peristaltic, hormone and enzyme secretion, muscular tone; these activities can’t be stopped by brain command, it’s automatically straight forward goes on.

Three factors determine the total Three factors determine the total energy need of an individual are :energy need of an individual are :

• The basal metabolism. This is the amont of energy required to carry on the vital processes of the body when awake. This includes the regulation of body temperature as an important entity in the basal metabolism

• The physical activity• The specific dynamic effect (action) of food.

This is extra energy required to metabolize the food, increase in heat production

The Basal Metabolic rate is measuThe Basal Metabolic rate is measurred ed by indirect calorimetric, indirect by indirect calorimetric, indirect measure of heat production using measure of heat production using Benedic-Roth apparatus by calculating Benedic-Roth apparatus by calculating the amount of othe amount of oxxygen consumed - ygen consumed - under the specific conditions under the specific conditions in basal in basal conditionsconditions..

Basal ConditionBasal Condition is the state of the is the state of the body in which :body in which :

• 12 – 16 hours after the last meal• Lying position, awake• No physical activity an hour before the

test• Relax - without emotional feeling• Normal body temperature• Room temperature should be 21-250C,

Normal humidity - comfortable

Numerous experiments on people of all ages shows Numerous experiments on people of all ages shows 1 ltr of O1 ltr of O22 is equal to is equal to 4,825 Cal4,825 Cal (kcal) in the (kcal) in the conditions for basal metabolic test.conditions for basal metabolic test.

Suppose a young woman consumes 1,200 cc OSuppose a young woman consumes 1,200 cc O22 in in a 6-minute test of a 24 hour period, her basal a 6-minute test of a 24 hour period, her basal heat expenditure is :heat expenditure is :10 x 1,200 x 24 10 x 1,200 x 24 = 288 ltr O= 288 ltr O22 in 24 hour in 24 hour 1000 1000 = 288 x 4,825 = 1,390 Cal = 288 x 4,825 = 1,390 Cal

BM rate approximately 1 Cal/Kg/h for men and BM rate approximately 1 Cal/Kg/h for men and about 0.9 Cal/Kg/h for women.about 0.9 Cal/Kg/h for women.The range of BMR for normal adults is 1,300 – The range of BMR for normal adults is 1,300 – 1,700 Cal1,700 Cal

Fundamental points about metabolism :

• Each reaction does not occur in isolation but provides a substrate.

• Pathways producing a continue process.

• Metabolic map.• Some of the reactions are one way.• Concepts & purpose of reactions

Metabolic pathways can be classified as either catabolic or anabolic.

Catabolism is the breakdown (degradation) of energy-rich complex molecules :

protein CO2, H2O, NH3

Anabolism is the synthesis of complex molecules from simpler ones; protein from amino acids.

Catabolic pathways names end is lysis meaing to breakdown.

Glycogenolysis glycogen breakdownProteolysis protein breakdownLipolysis fatty acid breakdownGlycolysis glucose breakdown

Anabolic pathways names end in genesis meaning to create.

Glycogenesis glucose synthesis, protein synthesisLipogenesis fatty acid synthesisGluconeogenesis glucose synthesis

The transfer of energy in reactions; when chemical bound breaks, energy can be released as heat, captured in another chemical bound, or both.

The site of reactions; metabolic work is going on all the time within the cells. Catabolism of energy-rich compound (carbohydrate, protein & fat); anaerobic reactions in the cytosol; aerobic reactions occur in the mitochondria.

Regulations of pathways: metabolic reactions mostly require enzymes (or hormones) to facilitate their action. Enzymes need coenzymes. The enzymes are subject to strict regulation to ensure that :

• The rate of the pathway is adapted to the cell’s needs

• Anabolic & catabolic pathways are not active at the same time.

COMPLETE CATABOLISM

CH & lipids CO2 + H2O + energy

Amino acids CO2 + H2O + NH3 + energy

Production of H2O & energy in the mitochondria :

H2 + O2 H2O + energy The energy potential produced, could form high energy phosphate molecules (ATP & GTP)

ADP + phosphate + energy ATPGDP + phosphate + energy GTP

The breakdown of high energy phosphate molecules will occur if the cells need energy.

ATP ADP + energy

Functions of the energy released :• To conduct nerve impulse (electric)• Actin & myosin contraction (mechanic)• Transfer of molecules across membrane

(osmotic)• Heat formation (thermic)• Anabolism (chemic)

Each organ has a preferential fuel; the substrate prefers to be used for energy production.

Glucose : brain, red blood cells, adrenal gland and muscle in anaerobic activity and high intensity of aerobic activity

Fatty acids : heart, liver, smooth muscle and skeletal muscle in low intensity of aerobic activity

Branch chain amino acids (BcAA): skeletal muscle.

Other amino acid: liver

Result condition between energy intake and energy expenditure determine the energy status

Energy Expenditure Energy Intake

Energy status assessment for children measure weight for age

Energy status assessment for adults weight for height: Body Mass Index (BMI)

BW (kg) H (m)2

Balanced equilibrium energy : if energy intake appropriate with the energy expenditureSurplus of energy : if energy intake larger than energy expenditure energy storage increase :

• CH stored as glycogen (limited) in liver & muscle and as lipid (abundance)

• Fat stored as lipid.• Protein stored as lipid.

Daily amount of energy intake depends on : food class, quantity per portion, and frequency of food intake per day

Nutrient composition & amount of energy per 100 grams food stuff are available in Food Composition List (Table). Food stuff weight comes from Household measurement.

DAILY USAGE OF ENERGY

Total Energy Expenditure = TEE : sum ofBasal Energy Expenditure (BEE)Physical Activity (PA)Specific Dynamic Action of Food (SDA)Thermic Effect of Food (TEF).

The calculation :TEE = BEE + PA + SDA (TEF)

Harris & Benedict calculation for BEEMen : 66 + (13,7 x BW kg) + (5 x BH cm) – (6,8 x age)Women : 665 + (9,6 x BW kg) + (1,7 x BH cm) – (4,7 x age)

Simple calculation for BEE (Wilson)Men : 1 Kkal / BW kg / h = 24 Kkal / BW kg / dWomen : 0,9 Kkal / BW kg / h = 21,6 Kkal / BW kg / d

Factors that influence BEE

Body weight, height, age, gender/sex, growth, temperature, muscle mass, sleep, endocrine activity, nutrition status

Age : above 20 BEE will decrease 2% every 10 year.Gender : BEE in men > women (at age > 10 year)Growth : highest for baby and adolescence.Height : the taller the higher BEE.Muscle Mass : the greater the higher BEE.

Temperature : every 100C elevation of body temperature (above 370C) BEE will increase 13%.Sleep : BEE decrease 10%.Endocrine : − hyperthyroid BEE increase 75-100%

− hypothyroid BEE decrease 30-40%− right before menstruation BEE

slightly increase and during menstruation BEE decrease

Nutrition status : BEE decrease in PEMPregnancy : BEE increase 12-25%

The rate of basal metabolism is influenced by : Body size Shape (surface area) Sex (women have 6-10 % lower than men) Age (BMR is high per unit surface area in

first 2 years of life) Activity of the endocrine glands (thyroid

gland regulates the rate of energy metabolism and any change in thyroid activity will be reflected in the metabolic rate : in hypothyroidism BM is reduced 30-40 %)

Sleep (BM 10% lower than awaking state) Body temperature (an elevation of body

temperature above 370C will increase BM by 13% per 0C)

Every physical activity needs energy above BMR

Energy Cost of Physical Activities

Activity Cal/KgBW/Hour

Bicycling (fast) 7,6

Bicycling (slow) 2,5

Dancing (foxtrot)

3,8

Dancing (waltz) 3,0

Dish washing 1,0

Driving 0,9

Table tennis 4,4

Marathon run 7,0

Sawying 5,7

Walking 5 km/h 2,0

Writing 0,4

Playing piano 2,0

Sewing 0,6

Energy for Physical Activity (PA)

• PA very light = 10-30% BEE• PA light = 30-50% BEE• PA moderate = 50-80% BEE• PA heavy = 80-100% BEE• PA very heavy = > 100% BEE

Level of Activity

• Very light - Activity in sitting position, bedrest• Light - Teacher, lecturer, general

practioner, housewife• Moderate - Farmer, student (+sport),

moderate build worker• Heavy - Athlete during TC, unskilled

worker, manual laborer, army during training

• Very heavy - Sawyer of wood, blacksmith, ricksaw carrier, becak driver

SDA or TEF

SDA / TEF is the amount of energy used for digestion, absorption and transportation of food consumed.

• SDA of protein 30% BEE• SDA of carbohydrate < protein• SDA of fat the lowest

SDA of Indonesian food on the average is 10% of BEE, more likely (dominant) of CH

SDA of food is the amount of energy required to digest mixed food (Carbohydrate, protein, lipid, fruit & vegetable).

Approximately 10% of BM is required as the SDA of food; especially in Asian’s meal/food intake more dietary fibres contents (vegetables and fruits) daily consumed.

60 Kg, BM = 1440 Cal 24 Cal/kg SDA = 144 Cal Total = 1584 Cal (BM+SDA)

Western people consumes less dietary fibres SDA : 6% - 8% of BM

It is not easy to measure factor of activity, especially in children (due to bone growth), pregnant or lactating women and for those who are in reconvalescence state. Therefore FAO (1957) recommends a general reference of men and women as follows

Reference Men Reference Women

• Age 25 y.o• Healthy• 55 Kg• Lives in temperate zone

(Europe)• Activity

– light activity 8 hours– mild activity 4 hours– walking 5 km 2 hours

• 3200 Cal/day

• Age 25 y.o• Healthy• 55 Kg• Lives in temperate zone

(Europe)• Activity

– housework– light individual work

• 2300 Cal/day