This document discusses the nutritional requirements and assessment of proteins in Indian diets. It notes that the main sources of energy in predominantly plant-based Indian diets are carbohydrates, fats, proteins, and dietary fiber. It explains that dietary fiber can provide energy through fermentation in the colon. The document also outlines two methods for assessing protein quality: amino acid score and net protein utilization. Finally, it identifies the nine essential amino acids that must be obtained through diet since the body cannot synthesize them in sufficient amounts.

1. NUTRIONAL
REQUIREMENTS
By
-DHARANITHARAN M

2. The main source of energy in Indian diets, which are
predominantly plant food based, are carbohydrate, fat,protein
and dietary fibre. The following rates:They supply energy at
Protein - 4 kcal/g
Fat - 9 kcal/g
Carbohydrate - 4 kcal/g
Dietary fibre - 2 kcal/g
SOURCE OF ENERGY

3. • Dietary fibre forms an indigestible and importantcomponent of
plant food and was never earlier considered as source of
energy.
• These dietary fibres (soluble and insoluble) undergo
fermentation in the colon and yield short chain fatty acids, such
as butyric, propionic and acetic acids which are utilized as a
source of energy by the colon cells and by the liver.
• Hence they are known to yield energy from fermentable fibre
and no energy from non-fermentable fibre. In conventional
foods, 70 per cent of fibre is fermentable.

4. ASSESSMENT OF PROTEIN
(a) PROTEIN QUALITY
The quality of a protein is assessed by comparison to
the"reference protein" which is usually egg protein.
Two methods of assessment of protein quality needs
mention:
(i) Amino acid score
(ii) Net protein utilization(NPU)

5. (i) Amino acid score:
It is a measure of the concentrationof each essential
amino acid in the test protein expressed as a percentage of
that amino acid in the reference protein.
The amino acid (or chemical) score is somewhere between50
and 60 for starches, and 70 and 80 for animal foods

6. (ii) Net protein utilization (NPU): It is a product of digestibility
coefficient and biological value divided by 100 (8). The NPU
gives a more complete expression ofprotein quality than the
amino acid score. It is a biologicalmethod that requires
special laboratory facilities.

7. (b) PROTEIN QUANTITY
The protein content of many Indian foods has been
determined and published in food composition tables. One way
of evaluating foods as source of protein is to determine what per
cent of their energy value is supplied by their protein content.
This is known as Protein-Energy Ratio (PE ratio or percentage).

10. The protein intake must also satisfy the need for
essentialamino acids.
The 2007 WHO Expert Committee Report
onEnergy and Protein Requirements gives current
estimates ofamino acid requirements (in mg/kg per day)
for adults.These are reproduced in Table
AMINO ACID REQUIREMENTS

12. ESSENTIAL AMINO ACIDS
Essential amino acidsProteins are made up of
smaller units, called amino acids.
Some 20 amino acids are stated to be needed by
the human body, of which 9 are called "essential" because the body
cannot synthesize them in amounts corresponding to its needs, and
therefore, they must be obtained from dietary proteins.
They are: leucine, isoleucine, lysine, methionine,
phenylalanine, threonine, valine, tryptophan and histidine.
Evidence is now accumulating that histidine is essential even for
adults.

13. THANK YOU