Nutrition

Part 3

Health

Health is defined by the World Health Organisation of United Nations as a "state of complete physical , mental and social well-being and not merely an absence of disease or infirmity.

Food

Food may be defined as anything eaten for drunk which meets for energy , building , regulation and protection of the body . In short food is raw material from which our body is made.

Dietetics

"Dietetics is the practical application of the principles of Nutrition . It includes the planning of meals for will and the sick."

Good nutrition means " maintaining a nutritional status that enable us to grow well and enjoy good health".

Nutrients

Nutrients are organic and inorganic complexes contained in the food we eat daily. These include water proteins carbohydrates vitamins and minerals etc. There are 50 different nutrients which are normally supplied through the food. These are of two types__

 

* Macronutrients

* Micronutrients

Macronutrients

Protein fat and carbohydrates are macronutrients. These are called proximate principles because they form the bulk of our food. In Indian diets , they contribute to the total energy in the following proportions Protein : 10 to 15 % , Fats : 10 to 30% , CHO : 60 to 80%

Micronutrients

Vitamins and minerals are micronutrients because they are required in small amount. Micronutrients do not supply energy but they play an important role in regulation of metabolic activities and helps in utilisation of macronutrients.

Nutritional status

Nutritional status is the condition of health of the individual as influenced by the utilisation of the nutrients or it is a state of our body as a result of food we consume . Nutritional status can be good , fair or poor.

Energy

Energy is defined as the capacity to do work. Energy is a prime requisite for body function and growth . The energy  produced in the body may be measured and expressed in units of work (joule) and unit of heat (kilocalories).

Kilocalories

A Kcal is the amount of heat required to raise the temperature of of 1 litre of water by 1 degree Celsius (1°C).

1 Kcal =4184 joules = 4.184 kJ

The nutritional value of protein CHO , Protein and Fats eaten in the diet may be expressed in kilojoules per gram or kcal per gram.

1 gm of carbohydrates provides 4 Kcal (17kilojoules)

1 gm of Protein provides 4 Kcal (17kilojoules)

1 gm of Fats provides 9 Kcal (37kilojoules)

Metabolism

Metabolism is the sum total of building up reactions (anabolism) and breakdown reactions (catabolism) going on inside the body of a living organism.

Metabolic Rate

Metabolic rate is the rate at which energy is released from the fuel molecules inside the cells. This  rate can be estimated by measuring oxygen uptake or carbon dioxide excretion.

BMR ( Basal metabolic rate)

Basal metabolic rate is the amount of of energy expressed in calories that a person needs to keep the body functioning at rest.

Men = 66 + (13.8 *  weight in kg ) + (5 * Height in cm ) -. 6.8 * Age

Women = 655 + ( 9.6 * weight in kg ) + ( 1.8 * Height) - ( 4.7 * Age )