Human Nutrition
Supervision
Prof. Dr. Mervat Salah
Intended Learning Outcomes
-
By the end of this lecture, students will
have a general overview on the body
composition.
-
As well as some basics of energy.
Facts about Body weight
Body is composed –
water, fat, muscle, bone,minerals
 Composition varies with age
 Controlled by hormones, diet,
exercise, stress etc.
Body Mass Index = wt (kg) / ht 2 (m)
 Ideal range = 19 – 23 for Indians
 Over weight BMI is > 23 – 26,
 Waist to Hip ratio (WHR) – Central obesity
 obese >27
Ideal = 0.8
Nutrition & wellness - Nutritional perspective. Drmervat salah.
Body Mass Index indicator of health risk

eg – 75 kg / 1.7 X 1.7 m = 26
BMI class
< 18.5
18.5 - 22.9
23 - 24.9
> 25
Presumptive diagnosis
Underweight
Normal
Overweight
Obese
Nutrition & wellness - Nutritional perspective. Drmervat salah.
Composition Of The Body
A normal chemical composition for a
man wieghing 65kg is
protein……….11kg……17 %
fat………………9kg.......13.8%
cho……………..1kg…….1.5 %
water………….40kg…….61.6%
minerals………..4kg……..6.1%
Functions Of The Food
There are several biological functions
of food :

1- Source of energy (fat and cho )
2- building material ( pt and ca, ph )
3- regulating and protective agent
NUTRIENT
BODY FUNCTION
FOOD SOURCES
Carbohydrate
Energy, protein sparing –
4kcal/g
Cereals, pulses, veg,
fruits
Protein
Growth, repair, energy,
enzymes, antibodies,
hormones
Pulses, meat, fish,
milk products, egg,
cereals
Fat (lipid)
Energy, EFA, fat-sol vit,
insulation.
Fats, oils, meat, fish,
nuts dairy products
Minerals
Skeletal, growth , blood
clotting, immunity
Vitamins
Vision, immunity, bone,
teeth, metabolism
Dairy, GLV, fruits,
whole grains
meat, veg, legumes,
organ meat
nuts
Nutrition & wellness - Nutritional perspective. Dr. Mervat salah
NUTRIENT SUPPLY
FOOD
1.
2.
3.
4.
5.
6.
7.
8.
Cereals
Pulses
Milk
Vegetables
Oils / fats
Fruits
Sugar
Meat
Amount
Energy
Protein
CHO
g/ml
Kcals
g
g
100
100
100
100
20
100
20
100
350
340
65
35- 55
180
30-55
80
80-140
6-12
18-25
3-5
1-2
1-1.5
12-22
60-70
60
8
8-15
10-15
20
-
Fat
g
1-2
1-5
4-6
20
3-13
Energy Value Of Food
1gm of Fat give 9 calories
1gm of Protein give 4 calories
1gm of carbohydrates give 4 calories
carbohydrates and fats are the preferred
energy sources , protien will be used for
energy if cho and fats are not available in
the diet and may build up of toxic
byproduct (ketones) in the blood .
Sources of Fuel
Protein, Fat, Carbohydrates
Substrate choice depends
І
Intensity & duration of exercise
Fitness level
Dietary intake
Energy is used in 3 ways
1 – Digesting food
10%
2 - Physical activity
25%
3 - Basal Metabolic rate ( BMR) 65%
BMR – all functions that support life 24 hours
Can’t change the percent
But
You can change your energy demand
Basal metabolic rate(BMR)
(BMR) is affected by several factors :
1-Body composition and surface area .
2- Sex women lower than men .
3-Age the highest rate during infancy .
4- Body temperature increase in cold fever
5-Physiological status decrease in
starvation ,increase in illness .
6- Effects of hormones thyroxin
Energy Requirements
Energy requirements are affected by :
- Body size
-Basal metabolic rate
-Activity
-Pregnancy (300cal)
-Lactation (500 cal)
-Age
-Climate (worm climate need less cals )

Total Daily Energy Requirement
TDR
TDR
BMR
EEA
SDA
= BMR + EEA + SDA
= total daily requirements
= basal metabolic rate
= energy expenditure of activity
= specific dynamic action of food
BMR
For adults
BMR = Ideal Body weight x 25
decease 2% every 10 years after age 20
For age less than 20 years
BMR =1kcal / m2 /hr - or - 55 – age (yr)
the area of the body from tables
Energy Expenditure Of Activity
-EEA deferent from one to one ,
-the average rang 1.1 to 8.4 cal /kg /hr
-the easy way is :
no active = 400 to 800 cal or 20%of BMR
light active=800 to1200 cal or 30% of BMR
moderate =1200 to1800 cal – 40%of BMR
very active=1800 to 3000cal _50%of BMR
Specific Dynamic Effect Of Food
It is the calorigenic effect of the food or
the calories need for the digestion
absorption transport process of the food
protein consume 15 % of its given cals
carbohydrates
6% of its given cals
fats consume only 2% of its given cals
Assignment
Rana fathi el zemrany
Recommended text book
Manual dietetic book