The normal body temperature is 98.4 degree farenheit or 36.9 degree celcius. The variation of temperature by one degree farenheit or half a centigrade is known as diurnal variation.The lowest levels of it are reached in the early hours of the morning and the highest point is between 5 and 7pm.

The  maintenance of normal temperature is done by an exact adjustement between the heat produced and that lost. This is controlled by the hypothalamus.

# It is otherwise known as the heat regulating centre.

#It is a layer of the brain that is also responsible for regulation of hunger and thirst.

#It is sensitive to the temperature of the blood passing through it like a thermostat.

PRODUCTION OF HEAT:

Heat is produced by metabolic activities in skeletal muscles and liver. The glycogen stored in the liver is converted into usable glucose and oxidized ,resulting in heat production. In order to maintain normal production of heat the requisite amount of fuel food is necessary.

To compensate for heat lost and to maintain the necessary production of energy to be used as heat or work, man requires food . The energy value of food has been standardized and is expressed in kilojoules(Kj) which are provided by:

Protein,yielding……………………………….17 Kj(4.1Kcal) per gram

Fats………………………………....................38 Kj (9.3Kcal) per gram

Carbohydrates…………………………………17 Kj (4.1Kcal) per gram

CARBOHYDRATES

PROTEINS

FAT

Calories are required for the following purposes:

*To prevent loss of weight,

*To maintain the body temperature,

*To provide the functional activity of all cells,tissues,glands and organs.

A man doing heavy manual work requires …………………….........14.7 megajoules(3,500Kcal)

A sedentary worker requires ………………………………………..10.5 megajoules(2,500Kcal)

A man at rest requires ……………………………………….............7.5 megajoules(1,800Kcal)

A patient in bed  requires ……………………………………….........5 megajoules(1,200Kcal)

Note: Infants and growing children require proportionately more joules than adults,per kilogram of body weight.

The foods which provide heat and energy are:

1.Carbohydraytes

2.Fats

3.Proteins

HEAT CONTROL:

The  metabolic activities must be adjusted to meet the varying demands made which includes

# Active work or conditions of rest.

#Intake of food and periods between meals.

#Emotional reactions of people.

#External pressure.

# Clothing worn  etc

Overheating may be due to a combination of a high external temperature, physical activity and inadequate sweating.

Heat Loss is mainly effected by functional activities of the skin. A certain amount of haet is lost by evaporation of moisture from the lungs and by excreta.

HEAT PRODUCTION: Fuel food oxidized in all tissues.

HEAT LOSS: Skin – Evaporation of sweat, radiation and conduction.

Lungs-  Evaporation of moisture

-