The main ingredients of food and energy derived

The food that we eat,  consists of carbohydrates, fats, proteins, water, mineral salts, and vitamins. All of these are essential for the normal functioning of life,

carbohydrates, fats, and proteins can provide energy and vitamins, minerals act as coenzymes, and chemical cofactors in many metabolic reactions.

Carbohydrates: carbohydrates provide energy to the body. it is 2 types.  

1. Sugar 
2. Starch.

Proteins: protein is required for muscle- building and repairing the worn-out tissues. proteins repair damaged cells or build new ones. protein obtained by,

1.  Animal sources,
2. and Plant sources.

Fats: fats provide us energy. it is necessary for the absorption of vitamins. sources of fats, 

1. meat, 
2. oil, 
3. ghee, 
4. nuts, 
5. butter,
6. cheese 
7. fish,
8. eggs.

Vitamins: vitamin needed for the proper functioning of the body. vitamin keeping our eyes, bones, teeth, and gums healthy.13 types of vitamins found. vitamins categorize into 2 groups, water-soluble and fat-soluble vitamins.

Minerals: minerals play an essential role in bones, teeth, and blood cell formation,. and maintaining a normal heartbeat.

Roughage or dietary fibers: roughage or dietary fibers do not have any nutrients values, but it helps in maintaining a healthy digestive system. lack of roughage in the diet our stool becomes hard and difficult to pass. result
constipation.

Water: water is very important for our body. almost 70% of our body weight is water. Water transports substances inside our body. Water regulates body temperature. We get water by drinking, but also get from food e.g milk, fruits, vegetables, juices, etc.

The standard chemical unit of energy is the calorie. One calorie is the amount of energy required to raise the temperature of one gram of water by one degree Celsius. 

In biology, kilocalorie (kcal.) is used and is equi­valent to 1000 calories. This is enough energy to raise the temperature of a liter (about one quart) of water by one degree Celsius.


Most proteins and all carbohydrates and fats can be degraded into carbon dioxide and water. The energy released from this breakdown is called the heat of combustion.


The heat of combustion of the three major types of compounds are as follows:


Fat - 9.5 kcal/gram,

Protein - 4.5 kcal/gram

Carbohydrate - 4.0 kcal/gram.


Thus, fats contain more energy per gram than carbohydrates and proteins.

Physiologically, more than one-half of the energy of combustion is lost as heat while the rest (about 38%) is converted into cellular energy in the form of ATP. The actual yield from one mole of glucose is 36 ATP plus heat, and the yield from a mole of fat is 463 ATP plus heat.

These are equivalent to .21 mole ATP/(gram glucose) and .55 moles ATP/(gram fat) respectively.

In terms of the energy actually produced in the cell, fats produce energy twice that of carbohydrates. Proteins yield about as much energy as carbohydrates on a per gram basis. Proteins, however, are rarely fully metabolized. 

Their constituent amino acids are used for cellular protein pro­duction. It takes less energy for the cell to utilize existing amino acids than to degrade them and then syn­thesize new ones.




Also, read:

Types of nutrients and their sources and functions