Quick Revision Notes: Class 6 Science

Chapter: Components of Food

Food is essential for all living organisms. It provides energy, helps in growth, repairs damaged parts of the body, and protects us from diseases.

Nutrients (पोषण तत्व): The components of food that our body needs for proper growth, functioning, and maintenance.
Balanced Diet (संतुलित आहार): A diet that contains all the essential nutrients in the right quantities, along with roughage and water, required for good health.
Obesity (मोटापा): A condition caused by eating too much fat-rich food, where excess fat gets accumulated in the body.
Deficiency Diseases (अभावजन्य रोग): Diseases that occur due to the lack of one or more essential nutrients (carbohydrates, proteins, vitamins, or minerals) in our diet over a long period.

Our food mainly contains five major components (nutrients):

In addition, food also contains Dietary Fibres (Roughage) and Water, which are essential for our body.

Nutrient / Component	Function / Role in Body	Rich Sources
Carbohydrates	Provide energy to the body ("Energy-giving foods").	Wheat, rice, potato, sugarcane, sweet potato, maize, banana.
Fats	Provide much more energy compared to carbohydrates ("Energy-giving foods").	Butter, ghee, milk, nuts, oil, egg yolk, meat.
Proteins	Essential for growth and repair of body cells ("Body-building foods").	Pulses (dal), gram, soybean, paneer, fish, meat, milk, eggs.
Vitamins	Protect the body against diseases and keep eyes, bones, teeth, and gums healthy.	Fruits (citrus fruits), green leafy vegetables, milk, liver.
Minerals	Needed in small amounts for proper growth and good health.	Salt, green vegetables, milk, fruits, grains.
Dietary Fibres (Roughage)	Helps in easy digestion and removal of undigested food.	Whole grains, pulses, fresh fruits, raw vegetables.
Water	Helps the body absorb nutrients and removes waste as urine and sweat.	Drinking water, milk, tea, juices, juicy fruits.

Procedure: Take a small quantity of a food item and add 2–3 drops of dilute Iodine solution to it.
Observation: If the food turns blue-black, it indicates the presence of starch.

Procedure: Take a small quantity of food, mash it, add a few drops of water, and then add 2 drops of Copper Sulphate solution and 10 drops of Caustic Soda solution. Shake well.
Observation: If the mixture turns violet (purple), it indicates the presence of proteins.

Procedure: Rub a small quantity of the food item on a piece of paper and crush it.
Observation: If the paper becomes oily/translucent and lets light pass through it partially, it indicates the presence of fats.

Vitamin / Mineral	Deficiency Disease / Disorder	Symptoms
Vitamin A	Loss of Vision (Night Blindness)	Poor vision, loss of vision in darkness (night).
Vitamin B1	Beriberi	Weak muscles and very little energy to work.
Vitamin C	Scurvy	Bleeding gums, wounds take longer to heal.
Vitamin D	Rickets	Bones become soft and bent.
Calcium	Bone and tooth decay	Weak bones, tooth decay.
Iodine	Goitre	Glands in the neck appear swollen; mental disability in children.
Iron	Anaemia	General weakness, pale skin.