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Most Class 6 students already know that junk food is "bad". Chapter 3 of the new science book asks a harder question: what is actually in your food, and how could you find out? This post explains the nutrients, the three simple food tests, how to read a food label with numbers, and the mistakes students make in this chapter. It is study help, not medical advice; for any health worry, talk to a doctor.
Where is this chapter?
"Mindful Eating: A Path to a Healthy Body" is Chapter 3 of Curiosity, the Class 6 NCERT science book marked Reprint 2026-27. You can read the full chapter on the NCERT site.
What are the nutrients and what does each do?
The chapter defines nutrients as food components that give energy, support growth, repair the body and protect it from disease.
Carbohydrates give energy. Sources: wheat, rice, maize, potato, banana. Sugar is a carbohydrate too.
Fats give energy and store it. Sources: ghee, oils, nuts, seeds.
Proteins are body-building foods for growth and repair. Sources: pulses, beans, peas, nuts, milk, paneer, eggs, fish, meat.
Vitamins and minerals are protective nutrients, needed in small amounts.
The book also lists dietary fibre (roughage) and water. Fibre gives no nutrients but helps the body get rid of undigested food. Its chart of deficiency diseases is worth learning as pairs: vitamin A and night blindness, vitamin B1 and beriberi, vitamin C and scurvy, vitamin D and rickets, iodine and goitre, iron and anaemia.
How do you test food for starch, fat and protein?
Starch: add 2 to 3 drops of dilute iodine solution. A blue-black colour means starch is present.
Fat: wrap the food in paper and press. An oily patch that lets light faintly through means fat.
Protein: a paste of the food with water, two drops of copper sulfate solution and ten drops of caustic soda solution. A violet colour means protein. The book says your teacher may demonstrate this, because these chemicals are harmful. Never handle them without your teacher.
Peanuts show both fat and protein, which is the chapter's point: one food can carry several nutrients.
Worked example: comparing two snack labels
The chapter prints labels for potato wafers and roasted chana, per 100 g. Wafers: energy 536 kcal, fat 35.0 g, carbohydrates 53.0 g, protein 7.0 g, fibre 4.8 g. Chana: energy 355 kcal, fat 6.26 g, carbohydrates 58.58 g, protein 18.64 g, fibre 16.8 g.
A snack pack is usually smaller than 100 g, so scale to a 30 g serving. Multiply each value by 30 ÷ 100 = 0.3.
Energy: wafers 536 × 0.3 = 160.8, about 161 kcal. Chana 355 × 0.3 = 106.5, about 107 kcal.
Fat: wafers 35.0 × 0.3 = 10.5 g. Chana 6.26 × 0.3 = 1.878, about 1.9 g.
Protein: wafers 7.0 × 0.3 = 2.1 g. Chana 18.64 × 0.3 = 5.592, about 5.6 g.
Fibre: wafers 4.8 × 0.3 = 1.44, about 1.4 g. Chana 16.8 × 0.3 = 5.04, about 5.0 g.
The World Health Organization says everyone older than 10 should aim for at least 25 g of naturally occurring dietary fibre a day. One 30 g serving of chana gives about 5 g, roughly a fifth (5 ÷ 25 = 0.2). Per serving, the wafers carry more fat and less protein and fibre than the chana. That matches the chapter's description of junk food: high in sugar and fat, low in protein, vitamins, minerals and fibre.
A common slip is to compare a 30 g pack of one food with 100 g of another. Always put both on the same amount first.
What is a balanced diet?
The book defines it as a diet with all essential nutrients, roughage and water in the right amounts for growth. Needs vary with age, activity and health. WHO's guidance adds two useful numbers: people over 10 should aim for at least 400 g of fruit and vegetables a day, and free sugars should stay below 10% of daily energy, which for a 2000-calorie diet is about 50 g or 12 level teaspoons.
The chapter also covers millets (jowar, bajra, ragi, sanwa), called nutri-cereals because they carry vitamins, iron, calcium and fibre, and food miles, the distance food travels from farm to plate.
Which mistakes cost marks?
Saying fibre is a nutrient. The book says it gives no nutrients but is still essential.
Mixing up the deficiency pairs. Learn them as six pairs, not one long list.
Thinking all carbohydrates turn iodine blue-black.
Calling a food "healthy" from one number on its label, such as low fat, without checking protein, fibre and sugar.
A one-week practice routine
Day 1: Start the week-long food record from Activity 3.1 and label each item with its main nutrient.
Day 2: Read two labels at home and scale both to 30 g, as above.
Day 4: From memory, write the six deficiency pairs and the three food tests. Recalling like this works better than re-reading; students who tested themselves remembered more a week later.
Day 7: Plan one balanced day of meals for a 12-year-old using foods from your region, as the book's "Learning further" section suggests.
If a term like "fortification" or "deficiency disease" needs a clear explanation, the Fermi Concept Library covers every concept in physics, chemistry, biology, mathematics and computing. For how food is grown and protected in later classes, see our guide to improvement in food resources.
Next time you pick up a snack, scale its label to 30 g and compare protein and fibre before you open it.
