Components of Food (Class 6 Science)

• Introduction

  • What are nutrients?
  • Need for varied diet (Meals with Chapati, dal, brinjals, etc.)
  • What do different items contain?

• Major Nutrients in Food

  • Carbohydrates
    • Function: Provide energy
    • Sources (Plant): Sweet potato, potato, sugarcane, papaya, melon, wheat, rice, bajra
    • Test: Iodine test (Blue-black color indicates starch)
  • Fats
    • Function: Provide more energy than carbohydrates ("energy banks")
    • Sources:
      • Plant sources: Groundnuts, nuts, til, soybean oil, coconut oil
      • Animal sources: Meat, fish, eggs, milk, ghee, butter
    • Test: Paper test (Oily patch/translucent spot indicates fat)
  • Proteins
    • Function: Body-building foods (Growth and repair)
    • Sources:
      • Plant sources (Dal/Pulses): Gram, moong, tur dal, beans, soyabean, peas
      • Animal sources: Paneer, meat, fish, chicken, milk, eggs
    • Test: Copper sulphate & Caustic soda test (Violet/Purple color indicates protein)
  • Vitamins
    • Function: Protect body against diseases, keep eyes, bones, teeth, gums healthy
    • Types: Vitamin A, Vitamin B-complex, Vitamin C, Vitamin D, Vitamin E, Vitamin K
    • Key Vitamins & Sources/Deficiencies:
      • Vitamin A: Carrots, papayas, milk, fish oil (Keeps eyes & skin healthy)
      • Vitamin B: Wheat, rice, liver (Energy metabolism)
      • Vitamin C: Amla, citrus fruits (lemon, orange), tomato (Fights diseases, healthy gums)
      • Vitamin D: Milk, butter, eggs, sunlight (Helps body use calcium for bones/teeth)

• Minerals

  • Function: Needed for proper growth and good health
  • Examples & Sources:
    • Iodine: Ginger, fish, spinach
    • Phosphorus: Banana, milk, rice, chilies
    • Iron: Apple, spinach, liver, bajra
    • Calcium: Milk, eggs

• Other Dietary Requirements

  • Dietary Fibres (Roughage)
    • Sources: Whole grains, pulses, potatoes, fresh fruits, vegetables
    • Function: Does not provide nutrients, but helps body get rid of undigested food
  • Water
    • Function: Helps body absorb nutrients from food; throws out wastes as urine and sweat
    • Sources: Liquids, milk, tea, fruits, vegetables

• Balanced Diet

  • Definition: Diet containing all essential nutrients, roughage, and water in right quantities
  • Importance: Depends on age, physical work, and body type
  • Cooking Rule: Do not wash rice/pulses excessively; do not overheat (destroys Vitamins, especially Vitamin C)

• Deficiency Diseases

  • Definition: Diseases caused due to lack of nutrients over a long period
  • Key Deficiencies & Symptoms:
    • Vitamin A $\rightarrow$ Loss of vision (Poor night vision, complete loss of vision in severe cases)
    • Vitamin B1 $\rightarrow$ Beriberi (Weak muscles, very little energy to work)
    • Vitamin C $\rightarrow$ Scurvy (Bleeding gums, wounds take longer to heal)
    • Vitamin D $\rightarrow$ Rickets (Bones become soft and bent)
    • Calcium $\rightarrow$ Bone and tooth decay (Weak bones, toothache)
    • Iodine $\rightarrow$ Goitre (Glands in the neck swell, mental disability in children)
    • Iron $\rightarrow$ Anemia (General weakness, pale skin)