📘 Class 6 CBSE Science – NCERT Textbook
🌟 Introduction
Food gives us energy, helps us grow, and keeps us healthy. But do you know what is inside the food that makes it so important?
These are called the components of food, and they include:
🔹 Carbohydrates
🔹 Proteins
🔹 Fats
🔹 Vitamins
🔹 Minerals
🔹 Roughage
🔹 Water
🍞 1. What do different food items contain?
Each food item is made up of one or more nutrients. Nutrients help us to grow, stay healthy, and carry out body functions.
✅ Table 1: Nutrients and Their Functions
| Nutrient | Function | Sources |
|---|---|---|
| Carbohydrates | Provide energy | Rice, wheat, sugar, potato |
| Proteins | Help in growth and repair of body | Milk, pulses, meat, eggs |
| Fats | Give energy, store energy for future use | Butter, ghee, oil, nuts |
| Vitamins | Protect us from diseases, help in body functions | Fruits, vegetables, milk |
| Minerals | Help in proper body growth and functions | Salt, spinach, fruits, milk |
| Roughage | Helps in digestion (adds bulk to food) | Vegetables, fruits, whole grains |
| Water | Helps in digestion, transports nutrients | Water, fruits, juices |
🧪 2. How do we test food items for nutrients?
There are simple experiments to check what a food item contains.
🔍 Table 2: Simple Tests to Detect Nutrients
| Test | How it’s done | Result (What you observe) |
|---|---|---|
| Starch (Carbohydrate) | Add iodine to food | Turns blue-black if starch is present |
| Protein | Add copper sulphate and caustic soda | Turns violet if protein is present |
| Fat | Press food on paper | Leaves greasy/oily spot |
👉 These are safe to do with teacher/guardian supervision.
🍗 3. Major Nutrients in Food
🧁 Carbohydrates
- Give instant energy
- Simple carbs (sugar) and complex carbs (starch)
🥚 Proteins
- Known as body-building food
- Needed more by growing children and people healing from injuries
🧈 Fats
- High energy nutrient
- Extra fats get stored in the body
🍊 4. Vitamins and Their Functions
✅ Table 3: Important Vitamins and Their Functions
| Vitamin | Function | Sources |
|---|---|---|
| A | Good for eyes and skin | Carrot, milk, mango |
| B | Helps in digestion and growth | Green veggies, milk, cereals |
| C | Keeps gums healthy, heals wounds | Lemon, orange, amla |
| D | Helps in forming strong bones | Sunlight, milk, egg yolk |
| E | Protects skin, acts as antioxidant | Nuts, seeds, leafy greens |
| K | Helps in blood clotting | Spinach, cabbage, broccoli |
🧂 5. Minerals and Their Functions
✅ Table 4: Important Minerals
| Mineral | Function | Sources |
|---|---|---|
| Calcium | Builds bones and teeth | Milk, cheese, leafy vegetables |
| Iron | Helps in formation of blood | Spinach, apple, jaggery |
| Iodine | Needed for proper growth | Iodized salt, seafood |
| Phosphorus | Builds bones and teeth | Milk, cereals |
| Potassium | Keeps muscles and nerves healthy | Banana, coconut water |
🥬 6. Balanced Diet
A balanced diet includes the right amount of all nutrients – carbs, proteins, fats, vitamins, minerals, roughage, and water.
✅ Table 5: Balanced Diet Plan Example (Indian)
| Meal Time | Food Item | Nutrient Provided |
|---|---|---|
| Morning | Milk and banana | Protein, calcium, carbs |
| Lunch | Rice, dal, vegetables, roti, salad | Carbs, protein, vitamins |
| Evening Snack | Sprouts, fruits | Protein, vitamins, minerals |
| Dinner | Roti, vegetable curry, curd | Carbs, protein, fat |
🧃 7. Deficiency Diseases
Lack of certain nutrients for a long time causes deficiency diseases.
❗ Table 6: Deficiency Diseases
| Nutrient Deficient | Disease | Symptoms |
|---|---|---|
| Protein | Kwashiorkor | Swollen body, weak muscles |
| Protein + Energy | Marasmus | Very thin body, weak growth |
| Vitamin A | Night Blindness | Cannot see in dim light |
| Vitamin B | Beriberi | Weak muscles, low energy |
| Vitamin C | Scurvy | Bleeding gums, wounds don’t heal |
| Vitamin D | Rickets | Weak bones, bent legs |
| Iron | Anaemia | Weakness, tiredness, pale skin |
| Iodine | Goitre | Swelling in neck |
📌 Key Points to Remember
- All living beings need food to survive, grow, and stay healthy.
- Different foods have different nutrients.
- A balanced diet helps keep us fit and free from diseases.
- Clean water and roughage are also very important for digestion.
- Lack of nutrients causes deficiency diseases.