NutritionThe process of absorbing nutrients from food and processing them in the body in order to

keep healthy or to grow

Food, Nutrition and Health

All living organisms need food for growth, work, repair and maintaining life processes. Food is made up of several components such as proteins, carbohydrates, fats, minerals and vitamins. Each of these components is required in a specific amount because each of them has a definite role to play in the body. A well balanced diet is necessary for the healthy growth of the body and mind. Good health is a necessary condition for our purposeful existence in this world. The World Health Organization (WHO) has defined health as “a state of complete physical, mental and social well being and not merely the absence of disease or infirmity”. A country can progress only if her citizens are healthy. It is the task of the Ministry of Health to provide good health care and other health facilities to everyone.

Components of Food

The components of food are certain organic substances and minerals found in food. They are called nutrients. Nutrients provide the body with energy and enable it to grow, repair and maintain itself. Hence it is important that we understand the exact role of nutrients in our food and recognize the various foods that provide these nutrients.

There are almost 40 essential nutrients of which carbohydrates, proteins, fats, vitamins, minerals, fibre and water are the most important.

Foods can be grouped on the basis of the nutrients contained in them and their functions in the body. Based on their functions they can be divided into three groups

Components of Food (cont’d)

Energy giving foods

Body building foods

Protective foods

Food group according to function

Major nutrient Food containing the nutrient

Energy giving Carbohydrate and Fat

Cereals like rice and wheatStarches like potato.Fat-ghee and oilSugar

Body building Protein

MilkMeat-Mutton, chiken, fishEgg whitePulses, like dals,gram,soya bean peas

Protective Minerals &Vitamins

Vegetables specially green leafyvegetables like spinach, cabbageand Dietary fibre ,beans and fruits

Three food groups and their sources

Nutrients

Nutrients are those chemical substances in foods that are essential for the proper functioning of your body.

Nutrients in your DietCarbohydratesProteinsFatsVitaminsMineralsRoughage/ FibreWater

Carbohydrates

Carbohydrates are compounds of carbon, hydrogen and oxygen. According to their chemical structure they may be simple or complex. Sugar and starch are complex where as glucose is simple.

The function of carbohydrates is to supply energy to the body for work and other physiological activities.

Example: Rice, wheat, pasta, potato, sweet potato, cereal, banana, sugarcane, ground provision, etc.

Proteins

Proteins are complex compounds which make up a major part of

all body cells, tissues and systems of the body.The proteins present in living organisms contain more than 20

amino acids and each of them have a specific function. Proteins, being highly complex compounds, cannot be used by our body in this form. By the action of digestive enzymes proteins are broken down into a simpler form i.e. amino acids which are assimilated into the blood in the intestine. The blood carries these free amino acids to the various body cells where they are regrouped to form specific proteins such as skin, muscles blood and bones. Thus proteins are essential for body growth and functioning.

Food items which are rich in proteins are meat, eggs, fish, milk, cheese, dhal, nuts etc.

Type of body proteins Functions

Enzymes

Biocatalysts, i.e. help in biochemical reactions occurring in the body all the time

Example : pepsin

Transport Proteins

carry different substances in the blood to different tissues

Example : Haemoglobin

Contractile proteins

Responsible for muscle contraction for movement and locomotion

Example : Myosin

Hormones

Some hormones are proteins. Hormones regulate body functions

Example : Insulin

Structural ProteinsForm parts of cells and tissues

Example : Collagen

Protective proteinsHelp fight Infections.

Example Anti bodies ,Gamma globulins

Functions of some proteins

Fats

Fats are also known as lipids. They are long molecules of fatty acids and an alcohol called glycerol. Fats contain the same elements as carbohydrates i.e., carbon, hydrogen and oxygen, but the oxygen content is lower.

The main function of fats is to provide energy. In fact they provide twice the amount of energy as that provided by the same amount of carbohydrate. Fats are involved in the formation of the structural materials of cells and tissues such as cell membrane and cell organelles. They are solvents for certain vitamins like vitamin A, D, E and K. Fats deposited around the internal organs like kidneys, livers, ovaries etc. act as a protective shock absorbing cushion. Fats can also be stored in the body for subsequent use when we eat food which has more energy than we can utilize while doing work, then this excess energy gets stored under our skin as subcutaneous fat. This fat insulates the body against cold and also acts as reserve source of energy.

Food substances that are rich in fats are butter, Ghee, Cheese, Milk, Egg yolk, Meat, Nuts. Groundnuts and oil. (Oil extracted from coconut, sunflower, mustard seed, sesame seed)

Vitamins

Vitamins are nutrients which are essential to life. They are organic compounds needed in small quantities, necessary for the healthy growth and maintenance of the body. Vitamins are found in all kinds of foods but, vegetables and fruits are particularly rich in vitamins.

Based on solubility, vitamins are grouped into two classes

Classification of vitamins based on their solubility

Minerals

Carbohydrates, fats and proteins are all carbon compounds or organic compounds. Minerals are inorganic substances, several of which are metals and their salts. Minerals do not supply us with energy but they are required to build bones and teeth, formation of red blood cells, clotting of blood, functioning of muscles, nerves and thyroid gland etc. Some of the important minerals required by our body are iron, iodine, calcium, copper, chlorine, phosphorus, potassium, sodium, sulphur, flourine, magnesium and zinc.

Roughage/FibreFibre is the fibrous material which is

indigestible and is eliminated from the body unchanged. It is made up of plant carbohydrate called cellulose. Though not a food, in a stricter sense, it is an important part of a balanced diet and is important for the normal functioning of the digestive system.

Roughage helps in retaining water in the body and adds bulk to the food and prevents constipation. Food items that are rich in roughage are fresh fruits and vegetables (salads), cereals, pulses with husk etc.

Water

Water is an important part of our diet. It constitutes 70% of the body weight. The quantity of water required by the body depends upon the age, type of work and climate. A lot of water comes from the food we eat. Eg. Fruits, vegetables. However most of the water needed by our body comes from plain “drinking water”, tea, coffee, milk, fruit juice etc. Water is a solvent that dissolves most enzymes, organic and inorganic substances.Water also helps to maintain the body temperature. Evaporation of water from the skin enables the body to cool down when the outside environmental temperature is high. Water provides a means for excreting body wastes (urine, sweat etc).

Balanced Diet

Diet is the food on which an individual lives. A balanced diet may be defined as the one which contains all the essential nutrients like carbohydrates, fats, proteins, minerals and vitamins in the correct proportion for the normal growth and development of the body. A balanced diet is related to the state of one's age, health and occupation. A food exchange chart will be useful in planning a balanced diet. In this exchange system, foods of specific servings are decided and standardized in terms of energy which is measured in (kcal)

Sl. No. Exchange

list

Serving size/or raw weight in

(g)

Carbo- hydrate (g)

Protein (g) Fat (g) Energy (k.cal)

1. Vegetable Green Leaf Other

½ Cup

½ Cup

6

6-10

Nil

Nil

*

Nil

30-40

50-60

2. Fruit Varies 10 Nil Nil 40

3. Cereal 25 19-21 2-3 - 85

4. Legumes and Pulses

25 15 6 * 95

5. Milk and Meat

½ Cup 75

6 Nil

3.5 7.5

4.0 6.0

65 85

6. Fat and Sugar

10 10

Nil 10

Nil Nil

10.0Nil

9040

 

Home Work 1. Write a passage describing how does

Nutrition impact on Physical Education.2. From your knowledge on Nutrition and

Nutrients help prepare a dinner and breakfast for an athlete preparing to do a marathon