Food and Digestion-Science

 Food and Digestion.

All living things need food. Food help them to grow and to stay alive. It gives us energy to do work and keeps us fit and healthy. We eat wheat, rice, vegetables, fruits and pules. Some of us also eat meat, fish and eggs. Food contains substance called nutrients which provide nourishment to the body.

NUTRIENTS IN FOOD

Food contains nutrients like proteins, carbohydrates, fats, vitamins and minerals. Food also contains roughages and water. 

•  Food rich in carbohydrates and fats give us energy- Bun, Potato
•  Food rich in proteins help us to grow- Fish, Eggs, butter, milk
•  Food rich in vitamins and minerals keep us fit and healthy-fruits

Carbohydrates:

Carbohydrates give us energy to work. People who do more physical work need more carbohydrates. Sugar and starch are two types of carbohydrates. Rice, wheat and potatoes contains starch.

Fats:

Fats give us more energy than starch. Fats help to keep our body warm. Extra fat is stored in the body for future use. However, we must not have too much fat. Foods that are rich in carbohydrates and fat are called energy-giving food. Oil, nuts and butter contain fat.

Proteins:

Protein help us to grow. This is why children need more proteins. Foods that are rich in protein called body-building foods. Egg, fish, meat, cheese, peas pulse contain proteins.

Vitamins:

Vitamins help to keep us healthy. We must regularly have foods which contains vitamins though our body needs a very small quantity of them. Fruit and milk contain vitamins.

Minerals:

Minerals help to formation of bones, teeth and blood. Calcium, potassium, sodium, iodine and iron are types of minerals. We get vitamins  and minerals from fresh fruits, vegetables, meat, fish, liver and milk. Foods rich in vitamins and  minerals keep us fit and healthy. They  are called protective foods

A balanced diet 

A balanced diet has a right amount of all the nutrients, that is, carbohydrates, fats, proteins, vitamins and minerals.

Digestion of Food

The food that we eat is not directly used to provide energy. It is broken down into a simpler form. The process of breaking down of food into a simpler form is called digestion.

The Process Of Digestive system

The process of digestion begins from the moment we put food into our mouth. Our teeth bite and chew it and break into small pieces. As we chew, the saliva in our mouth mixes with the food. Saliva is a digestive liquid secreted by the salivary glands. Saliva changes the insoluble starch in food into soluble sugar. From the mouth the food passes through food pipe to the stomach. Our stomach is a hollow, muscular bag. The food is churned here. The digestive juices in the stomach break down the proteins present in the food into a simpler form. From the stomach, the food is pushed into a long coiled tube called small intestine. The inside walls of the small intestine produce a juice that mixes with the food. The liver and the pancreas also pour their juice into the small intestine. These  juices help to completely  digest the food. The digested food almost like a liquid. The blood vessels presents in the walls of the small intestine absorb the digested food and carry it to all parts of the body. The undigested food passes into the large intestine. The blood vessels in the large intestine absorb extra water. The semi-solid waste is passes into the anus when we go to the toilet.

Some tips for proper digestion

• Have your food in fixed hours.
• Chew your food well before swallowing.
• Eat lot of green vegetables and fruits.
• Do not over eat.
• Drink plenty of water.

PRESERVATION FOOD

The process of treating food in a way that preserves its value for a long time is called preservation food. Cooked or uncooked food can be preserved in different ways like boiling, canning, refrigeration, pickling, jellying, drying.