This document discusses nutrition, dietetics, and protein. It defines nutrition as the science of food and its relationship to health. Dietetics is defined as the practical application of nutritional principles, including meal planning for healthy and sick individuals. The document then classifies foods by origin (animal or vegetable), chemical composition (proteins, fats, carbohydrates, vitamins, minerals), and predominant function (body building, energy giving, protective). Several pages are devoted to discussing protein in detail, including essential and non-essential amino acids, sources of protein, and assessing the nutritive value of proteins. The protein requirement for different groups is also outlined.

1. NUTRITION & DIETETICS
By DR. INDRAJEET KUMAR
Tutor
Department of Community Medicine

2. NUTRITION: The science of food and it’s relationship
to health.
DIETETICS: Practical application of the principles of
nutrition, it includes planning of meals for
the well & the sick.

3. CLASSIFICATION OF FOOD
A. CLASSIFICATION BY ORIGIN:
1. FOODS OF ANIMAL ORIGIN e.g meat, fish.
2. FOODS OF VEGETABLE ORIGIN e.g cabbage , carrot etc.
B. CLASSIFICATION BY CHEMICAL COMPOSITION:
1. PROTEIN PROXIMATE PRINCIPALS
2. FAT ( MACRO-NUTRIENTS)
3. CARBOHYDRATE
4. VITAMINS MICRO-NUTRIENTS
5. MINERALS
C. ON THE BASIS OF PREDOMINANT FUNCTION:
1. BODY BUILDING FOOD: Milk, Meat, Egg, fish, Pulses etc. (Protein)
2. ENERGY GIVING FOOD: Sugar, Root, Tubers, Fats & oils (Carb. & fat)
3. PROTECTIVE FOOD: Vegetables, fruits and milk (rich in vit. & minerals)

4. PROTEIN
PROTEIN
AMINO ACIDS
ESSENTIAL AMINO ACIDS:-
Body cannot synthesize
them in amount
corresponding to it’s need.
Total: 8
E.g: leucine, isoleucine,
lysine,
methionine, threonine,
Phenylalanine, valine,
tryptophane .
Semi-essential: Arginine &
Histidine
NON-ESSENTIAL AMINO
ACIDS: Body can
synthesize them in amount
corresponding to it’s need.
E.g: asparaginic acid,
glutamic acid,
proline,
serine etc.

5. BIOLOGICALLY COMPLETE PROTEIN:
Protein which contains all essential amino acids
are called biologically complete.
E.g: Milk protein & Egg protein
BIOLOGICALLY INCOMPLETE PROTEIN:
Protein which lack in one or more essential
amino acid are called biologically incomplete.
E.g: Rice, Wheat, Pulse etc.

6. SOURCES OF PROTEIN
ANIMAL SOURCE
Milk, Meat, Egg,
Fish etc.
VEGETABLE SOURCE
Pulses, cereals,
beans, Nuts,
Oil seed cakes etc.

7. SUPPLEMENTARY ACTION OF PROTEIN
MIXED DIET: e.g: cereal with
pulse. (rice+dal, Chapati+dal,
Dosa+sambhar, idli+sambhar,
khichri)
BIOLOGICALLY COMPLETE
Cereals (rice, wheat, maize)
deficient in lysine & threonine
but rich in Methionine.
BIOLOGICALLY INCOMPLETE
Pulses are deficient in Methionine
but rich in lysine & threonine.
BIOLOGICALLY INCOMPLETE

8. FUNCTIONS OF PROTEIN
 body building
 repair and maintenance of body tissue.
 maintenance of osmotic pressure*.
 Synthesis of certain substances like, anti-
bodies, enzymes, Hb., plasma protein,
hormones, coagulation factors.

9. ASSESMENT OF NUTRITIVE VALUE OF PROTEIN
1. DIGESTIBILITY CO-EFFICIENT: % of ingested nitrogen absorbed in
the body.
= nitrogen absorbed X 100
nitrogen ingested
2. BIOLOGICAL VALUE: % of absorbed nitrogen retained in
the body.
= nitrogen retained X 100
nitrogen absorbed

10. 3. NET PROTEIN UTILIZATION (NPU) = It is the product of
digestibility co-efficient and biological value
divided by 100.
= D . C X B . V
100
:- greater the NPU better the protein.
:- NPU of egg is 100. Hence called “Reference Protein”.
:- NPU of protein in indian diet is between 50 – 80.

11. ASSESSMENT OF PROTEIN STATUS
1. MID ARM CIRCUMFERENCE (for age 1-5yrs)
> 13.5cm - satisfactory.
12.5 – 13.5cm – mild malnutrition
< 12.5cm - severe malnutrition.
2. CREATININE HEIGHT INDEX
3. SERUM ALBUMIN (Normal = 3.5 – 5 gm/dl)
4. TOTAL BODY NITROGEN

12. PROTEIN REQUIREMENT
As per ICMR (Indian Council of Medical Research)
 for adult M/F : 1gm / kg body wt.
 for children : 1.5 gm / kg body wt.
 During pregnancy : + 14 gm / day.
 During Lactation : + 25 gm / day.