Hygiene of feeding, its ecological and
social problems.
Hygienic examination of quality of
food products. Scientific bases of
rational, preventive, dietary and
treatment feed.
Аuthor:
Lototska O.V
1
Nutrition may be defined as the science of
food and its relationship to health. It is concerned
primarily with the part played by nutrients in body
growth, development and maintenance. The word
nutrient or "food factor" is used for specific dietary
constituents such as proteins, vitamins and
minerals. Dietetics is the practical application of
the principles of nutrition; it includes the planning
of meals for the well and the sick. Good nutrition
means "maintaining a nutritional status that
enables us to grow well and enjoy good health".
'You are what you eat',
some people say.
If you eat rubbishy food,
you can't really expect to
grow up strong and
healthy.
But if you eat goodquality food, you've a
good chance of doing so.
That's just commonsense
really.
Main rules of healthy nutritional
Eating fruits, vegetables, and grain products that contain
fiber may help prevent heart disease
Limiting the amount of saturated fat and cholesterol in
your diet may reduce your risk of heart disease
Limiting the amount of total fat you eat may help reduce
your risk for cancer
Eating fiber-containing grain products, fruits, and
vegetables may help prevent cancer
Eating fruits and vegetables that are "low in fat" and
"good sources" of dietary fiber, vitamin A, or vitamin C may
help prevent cancer
In various historical times structure of nutrition
and character of a nutrition changed depending on
 development of industrial forces of a society,
 climate-geographical conditions,
 direction of economic activity and so on.
The character of nutrition of the population was
formed gradually depending on an economic and
cultural level of development of the country, in view of
national customs and features.
Through centuries, food has been recognized as
important for human beings in health and disease.
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Good nutrition is a basic component of health. The
relation of nutrition to health may be seen from the following
view points:
Growth and development: Good nutrition is essential for the
attainment of normal growth and development. Not only
physical growth and development, but also the intellectual
development, learning and behaviour are affected by
malnutrition.
Specific deficiency: Malnutrition is directly responsible for
certain specific nutritional deficiency diseases. Good nutrition
therefore
is essential for the prevention of specific
nutritional deficiency diseases and promotion of health.
Resistance to infection: Infection, in turn, may aggravate
malnutrition by affecting the food intake, absorption and
metabolism.
Mortality and morbidity: The indirect effects of malnutrition
on the community are even more striking - a high general
death rate, high infant mortality rate, high sickness rate and
a lower Expectation of life.
Nutrition as a science can be regarded as the
study of six main categories of food components
protein
fat
carbohydrate
minerals
vitamins
water
Water
Water is necessary to make up the loss caused by
its excretion in breath, sweat, urine, faces, and also
to renew all the various fluids and solid organs of the
body.
It is estimated that about 2 liters of water enters
the body daily as such or as a part of cooked food,
beverages etc. Out of which 1.37 - 1.81 liters is
excreted daily in urine, sweat etc.
Some important uses of water are:
 - As a solvent for transportation of nutrients in the
body.
 - It helps regulating body temperature through
evaporation from lungs and skin.
 - As an aid in removing wastes of metabolism in the
urine.
 - As an aid in functions like osmosis.
Diseases, that is direct or mediate
related with a nutrition
1. Alimentary disease,
illness caused by
deficiency or
surplus of
components of
nutrition.
The
secondary
illnesses of insufficiency
or excessive nutrition,
which is developed as
complication
on
a
background
of
wearisome
illnesses
(surgical,
infectious,
oncology and others.)
2.
3. Disease of
multifactor nature
that very much
frequently
develops on a
background of
genetic
predilection, for
example,
atherosclerosis,
gout, idiopathic
hypertension, etc.
4. Disease, which
are transferred by a
nutritional way
(some infections
diseases and
intestinal worms,
alimentary
poisonings).
5. Alimentary
intolerance atypical reaction to
nutrition, for
example alimentary
allergy,
idiosyncrasy.
Function of nutrition
Provision of energy
Body building and repair
Maintenance and regulation of
tissue functions -
On the basis of the above functions foods
have been classified as :
• (1) Energy-yielding foods: These are foods rich in
carbohydrate and fat, e.g., rice, wheat, potatoes,
sugar, fats and oils.
• (2) Body building foods: These are foods rich in
protein, e.g., milk, eggs, meat, liver, fish, pulses,
oilseed cakes.
• (3) Protective foods: These are foods rich in
vitamins, minerals and proteins, e.g., milk, green
leafy vegetables. Protective foods are so called
because they protect the body against infection,
disease and ill health.
Balanced diet is one, which will meet a person's
caloric need and contain all nutrients, particularly
proteins, and vitamins. In addition, the food should
satisfy the taste and desire of a person and should
have enough roughage to promote the peristalsis.
Balanced diet should have 50-60 % carbohydrates 3035 % fats and 10-15 % proteins with necessary
vitamins and minerals. A balanced diet must contain
foods from the above three groups.
1. Conformity of entering energy to energy losses.
In norm it is necessary the certain balance, or
equilibrium.
2. Conformity of chemical structure of alimentary
substances to physiological needs of an organism.
3. The maximal variety of a ration.
4. Keeping of an optimum regimen of nutrition.
Importance of the main components
of food in nutrition of the man
Nutrients are organic and inorganic
complexes contained in food. There are about
50 different nutrients which are normally
supplied through the foods we eat. Each
nutrient has specific functions in the body.
Most natural foods contain more than one
nutrient. These may be divided into :
(i) Macronutrients: These are proteins, fats and
carbohydrates which are
often
called
"proximate principles" because they form the
main bulk of food.
(ii) Micronutrients : These are vitamins and
minerals. They are called micronutrients
because they are required in small amounts
which may vary from a fraction of a milligram
to several grams.
PROTEINS
The word "protein" means that which is of first importance.
Indeed they are of the greatest importance in human nutrition.
Proteins are composed of carbon, hydrogen, oxygen, nitrogen
and sulphur in varying amounts. Some proteins also contain
phosphorus and iron and occasionally other elements. Proteins
differ from carbohydrate and fat in the respect that they
contain nitrogen. Proteins are made up of simpler substances,
called amino acids. These are the building blocks of protein
Some 22 amino acids are stated to be needed by the human
body, out of which eight are called "essential".
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Proteins are needed by the body:
For growth and development: They furnish the building
material, i.e. the amino acids from which the body proteins
are synthesized.
For repair of body tissues and their maintenance: It has
been shown that the body proteins are constantly being
broken down; they have to be replaced for which fresh
protein intake is required.
For synthesis of antibodies, enzymes and hormones:
Antibodies, enzymes and hormones contain protein. The body
requires protein to produce them.
Proteins can also furnish energy to the body, but generally
the body depends for its energy on carbohydrates and fats
rather than proteins.
Sources of protein
Animal sources:
Plant sources:
Protein requirements
Doctors recommended 1,0 g. protein/kg body weight for an
adult. Daily allowances recommended by experts of the World
Health Organization (Geneva, 1976) is 37 g of protein per day for
the standard man with mass of body 65 kg for professions of
average hardness (II group) and 29 g of protein for the standard
woman with body mass 55 kg.
Effects of protein deficiency:
The effects of protein deficiency may summarized as below.
 During pregnancy: Still birth, low birth weight, anemia
 Infancy and early childhood: Marasmus, kwashiorkor,
mental retardation, stunted growth and development
 Adults: Loss of weight, underweight, poor musculature, anemia,
increased susceptibility to infection, frequent loose stools, general
lethargy, incapacity to sustained work, delay in wound healing,
cirrhosis of liver, oedema, ascitis, etc.
Fats are composed chemically of carbon, hydrogen and
oxygen, only in different proportion than they are contained
in carbohydrates. There is less of oxygen in fats than in
carbohydrates. Fats are a form of concentrated food and like
carbohydrates, they are used as body fuels for the
production of heat and energy. As fats are not soluble in
water, the process of digestion changes the fat into an
emulsion form for their absorption into the body. Liquid fats
and those which melt at body temperature are somewhat
better digested than those which are much harder.
Fats serve the following functions:
• Dietary fat is a concentrated source of energy. One
gram of fat supplies 9 calories of energy.
• Fats are carriers of fat-soluble vitamins, e.g., vitamins
A, D, E and K.
• Dietary fat supplies "essential fatty acids". Linoleic
acid, one of the essential fatty acids, prevents scaly skin
formation.
• The fat layer below the skin plays an important role in
maintaining our body temperature.
• Fats provide support for many organs in the body
such as heart, kidney, intestine etc.
• Foods containing fats are tasty.
Functions: Fats serve the following functions:
• Dietary fat is a concentrated source of energy. One gram of
fat supplies 9 calories of energy.
• Fats are carriers of fat-soluble vitamins, e.g., vitamins A, D, E
and K.
• Dietary fat supplies "essential fatty acids". Linoleic acid,
one of the ssential fatty acids, prevents scaly skin formation.
• The fat layer below the skin plays an important role in
maintaining our body temperature.
• Fats provide support for many organs in the body such as
heart, kidney, intestine etc.
• Foods containing fats are tasty.
Animal sources:
These are ghee, butter, fat of meat,
fish oils, etc.
Vegetable sources: These are various
vegetable oils such as groundnut, gingely,
mustard, cottonseed, safflower (kardi) and
coconut oil.
CARBOHYDRATES
Chemically carbohydrates are
composed of carbon, hydrogen and
oxygen as the name implies.
Polysaccharides are various starches
which are converted into two
molecules saccharides i.e. cane sugar,
beet sugar, milk sugar and malt sugar.
These on further, glucose and
digestion change into single molecule
monosaccharides fructose.
Foods that are high in
carbohydrates: Breads,
pastas, beans, potatoes, bran,
rice and cereals.
The original source of all starches and sugars is green
plants. When plants have excessive sugar and they need
to store it, as reserve supply of food, plant body is
capable of changing its sugar into starch. Carbohydrates
are abundantly present in food. All carbohydrates have
to be changed into glucose and fructose before they can
be absorbed into the body.
1 gm of carbohydrates yields 4.1 calories of heat.
The daily requirement of carbohydrates varies from
50 to 60% of total energy intake.
The carbohydrates are chief sources of energy. In the
active muscles, the glucose is oxidized for the
production of energy and warmth. Glucose which cannot
be used immediately, is converted into glycogen and
stored in the liver and muscles or converted into fat and
stored under the skin.
There are three main sources of carbohydrate:
Starches:
These are present in cereals
(rice, wheat); roots and
tubers (potatoes).
Sugars:
(a) Monosaccharides: glucose, fructose,
galactose.
(b) Disaccharides: Sucrose, lactose, maltose.
(c) Cellulose: This is the tough fibrous lining
found in vegetables, fruits, cereal, etc.
It is hard to digest and has no nutritive value.
However, cellulose acts as "roughage" and
prevents constipation.
VITAMINS
These are complex organic substances contained
in food and are very essential for the normal
growth and nutrition of animals. In fact, they are
vital accessory food factors required for the
maintenance of optimum, health. They are present
in various foods in minute quantities and diet
devoid of vitamins, if taken for some period, gives
rise to certain diseases known as deficiency
diseases and may ultimately even cause death.
They do not supply energy but are simply
protective foods.
vitamins
Water-soluble
Vitamins
Fat -soluble
Vitamins
Thiamine (B1)
A (retinol)
Riboflavin (B2)
Niacin (B3)
Pyridoxine (B6)
Pantothenic acid
Cobalamin (B12)
Ascorbic acid
Folic acid
E (tocopherol)
D (calciferol)
K (menadione)
Nutritional Diseases:
1. Protein Calorie Malnutrition (PCM).
(i) Kwashiorkor. It results from consumption of very low
protein in diets of low biological values, yet providing just
enough energy to satisfy the needs of the child. This
condition is usually seen in children between the age group
of 1-4 years. This symptom is characterized by pitting
oedema, anemia, retarded growth, loss of appetite,
diarrhoea, scanty hair growth...
(ii) Marasmus. It is a clinical condition of protein energy
malnutrition, primarily due to total deprivation of the
requisite calories required by the body. It usually occurs in
the age group of 1/2 to 5 years. This syndrome is
characterized by failure to gain weight, wasting of muscles
and of subcutaneous fat. The child feels good appetite but
is irritable.
(iii) Marasmic-Kwashiorkor. Patients suffering from
Marasmic-Kwashiorkor show clinical symptoms of both
Marasmus and Kwashiorkor.
2. Protein Deficiency in Adults.
Protein deficiency in adults is also quite prevalent
in poverty areas.
Protein deficiency will result in adults having
 reduced weight,
 reduced subcutaneous fat,
 anaemia,
 greater susceptibility to infection,
 frequent loose motions,
 general lethargy,
 delay in healing of wounds
 oedema.
3. Mineral Deficiencies
(i) Deficiency of iodine in water
and feed leads to goitre.
(iii) Calcium deficient diets lead to
rickets and osteomalacia.
(iv) Iron deficiency diets lead to
anaemia,
(v) There are other important
minerals like copper,
(ii) Lack of flourine ( < 0.5 ppm) selenium etc. Usually their
requirements are so little that
in water leads to caries.
deficiency conditions do not
occur.
4. Vitamins Deficiencies
(i) Lack of vitamin A results
in xerophthalmia, Bitot's
spots, night blindness
and keratomalacia.
(ii) B Complex: Deficiency of
Thiamine leads to beri beri.
Niacin deficiency results in
pellagra.
Riboflavin
deficiency
symptoms
are
angular
stomatitis, cheilosis, scrotal
dermatitis and
corneal
vascularisation.
Other B Complex deficiencies also result in glossitis,
cheilosis and angular stomatitis
(iii) Vitamin C deficiency leads to scurvy, spongy bleeding
gums, haemorrhages in skin and other haemorrhages,
(iv) Vitamin D deficiency result in rickets and osteomalacia.
(v) Vitamin K deficiency leads to hypoprothrombinaemia,
which further leads to haemorrhages.
5. Problems of Overnutrition (eating too much)
Proteins/fats/carbohydrates
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Cardiovascular disease (Leading cause of death in
the western world); a primary cause is thought to be
ingestion of saturated fat and trans fat
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Some cancers
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Diabetes mellitus
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Insulin resistance
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Obesity The main features of obesity are overweight
and fatness. It is mostly caused by overeating and
intake of abundance of calories
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Metabolic syndrome
Vitamins
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Vitamin poisoning
(i) Hypervitaminosis A is at times caused by excess of vitamin A
therapy. The manifestation are headache, nausea, vomiting,
irritability and anorexia. Carotenaemia is also caused due to
excessive consumption of carrots which is characterised by
yellow skin with normal conjunctiva
(ii) The toxic manifestations of hypervitaminosis D are anorexia,
nausea, vomiting, thirst, polyuria and drowsiness. Calcium
and phosphorus levels in serum and urine are raised. Calcium
may be deposited in many tissues also
(iii) Fluorosis occurs if fluorine is available > 1,5 mg in water. It
is characterised by (a) dental fluorosis, i.e., mottled enamel of
teeth and (b) skeletal fluorosis i.e., dense bone formation,
severe spondylitis and even calcifications of ligaments of spine
and tendinous inflamation of other muscles in severe cases.
Food allergies
Some people have allergies or sensitivities to foods which
are not problematic to most people. This occurs when a
person's immune system mistakes a certain food protein for
a harmful foreign agent and attacks it. About 2% of adults
and 8% of children have a food allergy.
Commonly food allergens are gluten, corn, shellfish
(mollusks), peanuts, and soy. Most patients present with
diarrhea after ingesting certain foodstuffs, skin symptoms
(rashes), bloating, vomiting and regurgitation. The digestive
complaints usually develop within half an hour of ingesting
the allergen.
Rarely, the food allergy chelce can lead to anaphylactic
shock: hypotension (low blood pressure) and loss of
consciousness. This is a medical emergency. An allergen
associated with this type of reaction is peanut, although
latex products can induce similar reactions.