We all know that regular supply of food is essential for human beings in order to keep fit and to carry on all the life processes. In this lesson we will learn about quality of food and the problem of health, related with deficient or faulty food.

After completing this lesson you will be able to :

• differentiate between food and nutrient.
• describe the components of food.
• relate the calorific need of persons -with their age and occupation.
• explain the need of balanced diet.
• emphasise the need of special nutrition according to the age, occupation, pregnancy and state of health.
• correlate the protein deficiency with disorders.
• describe disorders caused due to mineral deficiency of iron, iodine and calcium.
• list the disorders due to vitamin deficiency and their symptoms.
• correlate overeating with obesity.
• explain the risk of intake of overdoses of iron and vitamins

- yields energy or heat

- builds up new cells(growth)

- repairs worn out (damaged) tissues .

- regulates body processes to maintain life

- aids in production ot useful body compounds

Food can be classified into three categories based on the function.

- Energy giving foods

- Body building foods

- Protective/regulatory foods

(i) Energy giving foods;- These are rich in carbohydrates and fats.

Example: cereals, sugar, fats,oils, roots and tubers.

(ii) Body building foods:- These are rich in proteins, vitamins and minerals

Example: milk. egg, meat, fish, pulses, nuts and oilseeds.

(iii) Protective/regulatory foods:- These are rich in minerals, vitamins, roughage and

water.

Example : Whole cereals, grean leaf^ vegetables, fruits.

Nutrients are the substances which help in maintaining proper health and are required for the survival of a living being.

- Macronutrients

- Micronutrients

Macronutrients (Nutrients in a large amount) Most part (bulk) of the food is due to

carbohydrates, fats, proteins and water contained in it.

Micronutrients (Nutrients in small amount) Vitamins and minerals form only a small

fraction of the total weight of the food.

Let us leam in some detail about these nutrients.

They release energy on oxidation.

Complete oxidation of one gram of carbohydrate yields about 17 kilo joules of energy One kilo calorie heat is required to raise the temperature of 1 litre of water through 1" C

The three types of carbohydrates that we consume in our food are:

(i) sugars (ii) starch (iii) cellulose

Cereals (wheat, rice, maize), millets (bajra, Jowar, barley), roots and tubers (potato, sweet potato, tapioca,)

Cane sugar, beet root, fruits (banana, mango, sapota "chicku") and milk.

Cell wall in fruits, vegetables, and cereals.

During digestion both starch and sugars are absorbed as glucose. The surplus glucose is changed into glycogen which is stored in the liver, for subsequent use.

Cellulose is a fibrous substance which is not digested by human body. However, it serves as roughage and facilitates bowel (stool) movement.

A normal person needs about 400-500 grams of carbohydrates daily in the diet. The percentage of carbohydrates in different food item is given in table 38.1 below :

Animals sources: Ghee, butter, fish, oil, meat, egg.

Plant sources : Vegetable oil from the seeds of coconut, mustard, sunflower, safflower etc.

Functions of fat other than supplying energy:

- form structural components of cell cytoplasm and cell membrane.

- help in absorption of fat-soluble vitamins (A,D,E and K)

- act as precursor of various hormones.

- can be stored for subsequent use by the migratory birds, hibernating frogs, pole bears etc.

- serve as insulators thus protecting from cold.

- stored fat provides padding to protect the vital organs of the body from shocks.

Doctors advise intake of oils (rich in smsaturated fatty acids) instead of ghee (rich i saturated fatty acids) to prevent cardiovascular diseases.

Proteins are complex organic compounds rich in carbon, hydrogen, oxygen, nitrogen Sometimes phosphorous and sulphur also occur in varying amounts, Proteins are needed by the body for:

- growth and development

- repair and maintenance

- the synthesis of antibodies, enzymes, and hormones

When consumed in excess of body needs, proteins can be used as a source of energy Proteins are made of simpler substance, the amino acids. Nutritionally, amino acids belong to two categories:

Animals sources : milk, egg, fish, meat, liver etc contain adequate amount of essential amino acids.

Plant sources : cereals, pulses and nuts are deficient in one or more essential amino acids.

Intake of more than one plant protein in the same meal (dal-roti, sambar-iii) can produce a mixture containing all the essential amino acids.

Vitamins are complex chemical substances required by the body in very small amounts. They do not yield energy but:

- actasbiocatalystinthebody

- are essential for good health

- protect the body from various diseases

- essential for the utilisation of other nutrients

Vitamins are grouped into two classes:

a) water soluble vitamins - vitamins B complex and C

b) fat soluble vitamins - Vitamins A, D, E and K

Since vitamins cannot be made in our body except for Vitamin D, they have to be supplied through food that contain them. Table 38..2 lists the vitamins and their sources as well as the daily requirements deficiency diseases and symptoms for 13-15 year old boys and girls.

Minerals are micronutrients required in varying amounts for proper functioning, normal growth and keeping good health of our body.

Minerals perform the following functions :

Table 38.2 lists the minerals, their sources, function, deficiency diseases and symptoms.

- essential for the transport and digestion of food material

- excretes wastes

- maintains the body temperature

- acts as solvent in reactions in the body

water is replenished by:

- drinking of plain water or through drinking of tea, coffee, milk and fruit juices, eating fruits, vegetables and fish

- some amount of water comes as a by-product of oxidation of glucose.

Our body needs energy to carry on various activities of life. We get this energy by eating food. The energy requirement of an individual depends on various factors like age, sex, food. The energy requirement of an individual depends on various factors like age, sex amount of work done (occupation), special needs like pregnancy and lactation. The average daily requirements of our body for different age groups are given below (Table 38.3)

Growing children, person engaged in hard physical work (labourers), pregnant women lactating mothers, sportsman, persons recovering from illness and person working in cold weather require more energy.

To maintain proper health, one needs the right type of food in right quantity, the nee geneally vary with age, sex, type of work and state of body etc. (Table 38.4)

A balanced diet has the following qualities:

-    meets the nutrient requirement of the body

-    consists of different types of food items

-    provides adequate amount of energy

Balanced dietvaries with age, occupation, and state of health. Under special conditions more food is required by an individual. Let us learn about it.

Growing children need more food in proportion to their body weight. They need.

-    extra protein to make new tissues for growth

-    more calcium and phosphorous for formation of bones and red blood cells.

-    Vitamin A for development of healthy eye sight

-    Vitamin C for general health

-    Vitamin D for healthy bones

2.    Nutritional needs for person in different occupation:

Persons doing hard physical work like rickshaw pullers, labourers, carpenter, mill workers etc. require food which is rich in energy, (carbohydrates and fats). Similarly, athletes also' require diet of high energy value.

3.    Nutritional needs during pregnancy and lactation

A pregnant women has also to feed the developing embryo, therefore, has special need of extra nutrients.

She needs :

-    extra protein for tissue growth

-    more calcium and phosphorous to form bones of the baby

-    more iron for making sufficient blood of the baby

-    more carbohydrates for herself because extra energy is required to carry out all the building processes linked with embryo.

Similarly, nursing mothers (who breast feed their babies), also need a special diet to take care of their additional requirements of lactations (milk formation). So their diet should contain more proteins, calcium and vitamins.

4.    Nutritional need depending upon the state of health:

The person recovering from illness need more proteins, minerals and vitamins in their diet to repair the damage caused by the ailment. If there is loss of blood due to surgery or an accident the patient needs more of proteins and iron to make up the loss of blood.

What is health and disease?

According to the Worid'health Organisation (WHO) health is defined as:

Disease :

Disease is a condition of the body or a part of it in which functions are disturbed or damaged.

Deficiency diseases :

The diseases which occur due to deficiency of one or more nutrients (proteins, carbohydrates, vitamins and minerals in our diet are called deficiency diseases.

Malnutrition: The condition resulting from lack of nutrients in diet is called malnutrition.

A large number of people in our country and developed countries, suffer from malnutrition. Malnutrition affects the health of the children adversely as it results in physical and mental retardation

The deficiency diseases are of three types:

1.         Protein Energy malnutrition (PEM)

2.         Mineral deficiency diseases.

3.         Vitamin deficiency diseases.

Let us learn in some detail about them.

PROTEIN ENERGY MALNUTRITION : (PEM)

Generally the growing children suffer from protein energy malnutrition as the required amount of proteins needed for their growth and development is not available. A number of children in the age group of 1 -5 years suffer from this disease. PEM is due to two reasons:

a)     Lack of proteins or carbohydrates or both in diet.

b)     More intake of carbohydrates than proteins.

Protein energy malnutrition results in two diseases :-

i.      Kwashiorkor and

ii.    Marasmus

This disease develops when mothers, stop feeding their babies with breast milk and the child is given traditional family food having low protein in it. (Figure 38.1 (i)

-     under weight

-     has protruding belly

-     skin is dark and scaly

-     has enlarged liver

-     has anaemia

-     suffer from repeated diarrhoea

-     stunted growth

-     loss of appetite

-     hair become reddish

(ii)     Marasmus :

It is caused due to the deficiency of carbohydrates, fats and proteins. It usually affects infant below the age of one year (figure 3 8.1 (ii))

-     wasting of muscles reduces the child to skin and bones.

-     folded skin.

-     Sunken eyes, thin face, thinning of limbs and abdominal walls.

-     retarded physical and mental growth.

-     ribs become prominent (pigeon chest).

-     Oedema and skin pigmentation are absent

Cure :     The child suffering from Kwashiorokor and marasmus can recover if adequate protein and carbohydrate rich ssfood is given.

Common deficiency diseases of iron, calcium and iodine are given below:-

Anaemia (Iron deficiency). Iron is important for the formation of respiratory pigment haemoglobin present in blood. Deficiency of iron results in reduction of red blood cells. This reduces the oxygen carrying capacity ofblood.

A person suffering from Anaemia:

- becomes pale

- tires easily

- loses appetite

- loses weight

Cure : By eating food stuffs rich in iron and Vitamin B12.

Example: eggs, meat, liver, milk, green leafy vegetables, such as spinach and fruits like apple, banana, guava. (Iron tablets tonics can supplement the food).

Deficiency of Calcium, Phosphorus and vitamin D

Calcium:- chief constituent of bones and teeth, regulate heart beat and

- muscle contraction, help in the clotting of blood. Calcium metabolism is closely related to phosphorus and vitamin D.

- Deficiency of vitamin D causes: Rickets in Children and Osteomalacia in adults

Rickets : (Figure 38.2)

- The bones become soft, get deformed or bend easily

- bow legs (bent legs)

- pigeon chest

- loss of teeth enamel (outer shiny layer in teeth)

- tender (soft) bones that tend to fracture easily.

Osteomalacia :

- Softening of bones

- Pain in bones and bones tend to fracture easily.

Cure :

Rickets and Osteomalacia can be prevented by giving diet rich in calcium like milk, cod liver oil, egg yolk, green leafy vegetable etc. Body exposure to sunlight.

Goitre :

Iodine is essential for the synthesis ofthyroxine (hormone produced by thyroid gland). Iodine deficiency causes thyroid gland to enlarge and swell, this is called goitre. (Figure 38.3)

Symptoms :

- Protruding eyes

- stunted growth

- pufty appearance

- irregular heart beat

- low intelligence

- Deficiency of ioding results in another disease called cretinism

symptoms

- stunted growth

- retarded mental growth

- delayed puberty

- low metabolic rate.

If a person continues to eat more food than required by his body, he soon becomes overweight and bulky. Excess of carbohydrates and fats instead of providing energy get accumulated in the body.

- Overeating
- insufficient exercise
- hormonal imbalance (deficiency of thyroxine) or other metabolic disturbances.

An obese person tend to have high cholesterol (fatty substance) deposited in blood arteries. This leads to hypertension (high blood pressure) atherosclerosis (hardening of arteries), coronary attack (heart attack), diabetes and respiratory problems).

The obese persons should be very careful in their diet. Some suggestions are:

- avoid fried food not to take high carbohydrate foods
- not to take saturated fats like ghee and vansaspati (hydrogenated vegetable oils)
- instead take unsaturated fats like oils, and that to in as little quantity as possible
- take regular physical exercise
- eat green leafy vegetables {to add roughage)
- get hormonal imbalance cured; if suffering

It leads to a condition called hemosiderosis (large deposits of iron in the liver). This may cause.

- Constipation
- diarrhoea
- Nausea
- Vomitring
- Heartburn Epigastric pain

Some people who are guided by unfounded beliefs tend to consume vitamins in excess amounts. An excessive intake of water soluble vitamins (vitamins B complex and C) may not cause any harm to the body because they are excreted out through urine. Intake of fat soluble vitamins (vitamins A and D) can be toxic (poisonous) to the body which may lead to certain diseases.

The disease caused by excessive presence of vitamins in the body is called hypervitaminosis.

Excess vitamin A accumulating in liver is toxic. This results in:-

- loss of hair
- drowsiness
- painful swelling of long bones
- loss of appetite
- nausea and vomiting

Excess of vitamin D lead to high calcium absorption in the intestine. This results in:

- deposition of calcium in soft tissues of body like kidney
- drowsiness
- nausea
- loss of weight.

• Food is required for the proper development of body.
• Food provides nutrients required for a healthy body.
• Carbohydrates, fats, proteins and water are macronutrients whereas vitamins and minerals are micronutrients.
• food has six components;
• Energy giver-carbohydrates and fats Body builder- Proteins, Vitamins & minerals Protective/regulatory- minerals, vitamins, roughage.
• The requirement of energy and different nutrients for the body are needed according to age, sex and profession as well as state of the body.
• A balanced diet provides proper amount of carbohydrate, fats, proteins, minerals. water and vitamins in food.
• a balanced diet is essential for proper growth and health of an individual.
• Malnutrition is the lack of essential nutrients or food elements in the diet. It results in deficiency diseases.
• An excessive intake of fat soluble vitamin A and D results in hypervitaminosis.
• An excessive intake of food for a prolonged periods results in obesity. An obese suffer from cardiovascular disease, respiratory problems and diabetes.

1.    Differentiate between

        (i) Marasmus and kwashiorkor.
        (ii) Rickets and Osteomalacia;
        (iii) Essential and non-essential amino acids

2.    give resons why do Indian children of 1 - 5 years develop PEM.

3. Why one should include more than one type of protein in the meals?

4. What is the importance of water in the body?

5. What is balanced diet? Why a pregnant women or a nursing mother need special diet?

6. Why should food contain roughage material? Name two sources of roughage in our diet.

7.    Why is polishing of rice not advisable? If a person alway consumes polished rice, what is likely to suffer from? Give two symptoms.

8. State four important functions of food.

9. If a child is not able to see in dim light, which two food stuffs will you advise him to eat. Give reasons.

1.    (a) Carbohydrates, fats, proteins, minerals, vitamins and water.

2. Nutrients required in large quantities are called macronutrients- carbohydrates fats, proteins and water.
        Nutrients required in small amounts are micronutrients e.g. minerals and vitamins.

3. (i) Water soluble-vitamin B and C

4. Butter

1. The condition resulting from lack of essential nutrients in diet is malnutrition

2. Protein calorie Malnutrition. marasmus, Kwashiorkor.

3. Anaemia

4. Any two-milk, cod liver oil, egg yolk, exposure to light.

1. Over eating, lack of exercises, hormonal imbalance.

2. Avoid fried food, carobohydrates, take regular exercise, eat green leafy vegetable (Any two).

3. Constipation, Diarrhoea, epigastric pain (Any two).

4. Excess presence of vitamins in the body. vitamin A and D.