Human Nutrition Supervision Prof. Dr. MervatSalah
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 Presumptive diagnosis < 18.5 Underweight 18.5 - 22.9 Normal 23 - 24.9 Overweight > 25 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%
FunctionsOf 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
NUTRIENTS – sources,functions Nutrition & wellness - Nutritional perspective. Dr. Mervat salah
NUTRIENT SUPPLY FOOD Amount Energy Protein CHO Fat g/ml Kcals g g g • Cereals 100 350 6-12 60-70 1-2 • Pulses 100 340 18-25 60 1-5 • Milk 100 65 3-5 8 4-6 • Vegetables 100 35- 55 1-2 8-15 - • Oils / fats 20 180 - - 20 • Fruits 100 30-55 1-1.5 10-15 - • Sugar 20 80 - 20 - • Meat 100 80-140 12-22 - 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 = BMR + EEA + SDA TDR = total daily requirements BMR = basal metabolic rate EEA = energy expenditure of activity SDA = 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 • Ranafathi el zemrany
Recommended text book • Manual dietetic book
