Introduction to the Topic

Welcome to NCERT Explained: Class VI Science, Chapter 2 - Components of Food! In our previous chapter, we explored where our food comes from. Now, we dive deeper into what actually makes up the food we eat every single day. Have you ever wondered why your parents tell you to eat your vegetables, finish your lentils, or drink milk? It is not just to fill your stomach; it is because your body needs specific chemical substances called nutrients to grow, stay healthy, and fight off diseases. This chapter helps us understand the magic inside our plates, breaking down our daily meals into essential components and teaching us how to maintain a healthy, balanced diet.

Key Concepts Explained

To understand how food works inside our bodies, we must look at the major building blocks of nutrition. Let's break them down into simple, easy-to-understand points:

1. What are Nutrients?

Nutrients are the necessary components that our body needs to function properly. The major nutrients in our food are named carbohydrates, proteins, fats, vitamins, and minerals. Additionally, our food contains dietary fibre (roughage) and water, which are equally important for our digestive system.

2. Carbohydrates and Fats: The Energy Givers

  • Carbohydrates: These are the primary energy providers for our body. Foods rich in carbohydrates include wheat, rice, maize, sweet potato, potato, sugarcane, and papaya. You can test for the presence of starch (a type of carbohydrate) in food using a simple iodine solution, which turns blue-black if starch is present.
  • Fats: Fats also give us energy—in fact, even more energy than carbohydrates gram for gram! Foods containing fats include butter, ghee, milk, nuts, and oil. A quick test for fats involves rubbing a food item on a piece of paper; if the paper becomes translucent and greasy, fats are present.

3. Proteins: The Body-Building Foods

If carbohydrates and fats are our fuel, proteins are our bricks and mortar. Proteins are essential for the growth and repair of our body tissues. Foods rich in proteins are often divided into plant sources (like gram, moong, tur dal, beans, soyabean) and animal sources (like paneer, meat, fish, eggs, and milk). Protein is especially critical during childhood and adolescence when the body is growing rapidly.

4. Vitamins and Minerals: The Protective Foods

  • Vitamins: Vitamins help in protecting our body against diseases. They also keep our eyes, bones, teeth, and gums healthy. Important vitamins include Vitamin A, Vitamin B-complex, Vitamin C, Vitamin D, Vitamin E, and Vitamin K. For instance, Vitamin A keeps our skin and eyes healthy, while Vitamin C helps the body fight against many diseases.
  • Minerals: Minerals are needed by our body in small amounts for proper growth and good health. Examples include calcium for strong bones and teeth, iron for making blood (preventing anemia), and iodine.

5. Roughage and Water

Not all components of food provide direct nutrition, but they are vital for survival. Dietary fibre, also known as roughage, mainly consists of plant products provided by whole grains, pulses, potatoes, fresh fruits, and vegetables. Roughage does not provide any nutrients to our body, but it is an essential component of our food and helps our body get rid of undigested food. Water helps our body absorb nutrients from food and assists in throwing out wastes from body as urine and sweat.

6. Balanced Diet

A diet that contains all the necessary nutrients in the right quantities, along with adequate roughage and water, is called a balanced diet. Eating a balanced diet does not mean buying expensive food; a simple meal of dal, roti, rice, vegetables, and curd can provide all the required nutrients. However, cooking food improperly—such as washing vegetables after cutting them or overboiling rice—can destroy valuable vitamins and minerals, especially Vitamin C.

7. Deficiency Diseases

If a person eats food that lacks one or more nutrients for a long time, they may suffer from certain diseases or disorders called deficiency diseases. For example:

  • Lack of carbohydrates and proteins together can cause a person to become very lean, weak, and unable to grow properly.
  • Lack of Vitamin A causes loss of vision (night blindness).
  • Lack of Vitamin B1 causes beriberi (weak muscles and very little energy).
  • Lack of Vitamin C causes scurvy (bleeding gums, wounds take longer to heal).
  • Lack of Vitamin D causes rickets (bones become soft and bent).
  • Lack of Calcium causes bone and tooth decay.
  • Lack of Iodine causes goitre (swollen glands in the neck).
  • Lack of Iron causes anemia (general weakness).

Summary & Key Takeaways

Let's quickly review the most important points from this chapter to help you ace your exams and live a healthier lifestyle:

  • The major nutrients in our food are carbohydrates, proteins, fats, vitamins, and minerals.
  • Carbohydrates and fats mainly provide energy to our body.
  • Proteins and minerals are needed for the growth and the maintenance of our body.
  • Vitamins protect our body against various diseases.
  • A balanced diet provides all the nutrients that our body needs, along with adequate roughage and water.
  • Deficiency of one or more nutrients in our food for a long time may cause certain diseases or disorders.