Food and Nutrition

Learning Objectives

Students will understand the sources of food, identify the nutrients present in food, learn about balanced diets, vitamins, minerals, and healthy eating habits. They will also study deficiency diseases, food testing methods, and the importance of proper nutrition for growth, energy, and overall health.

Introduction to Food and Nutrition

Food is one of the basic necessities of life. It provides the energy needed for daily activities, supports growth, repairs damaged tissues, and protects the body against diseases. Different foods contain different nutrients, each performing a unique function in keeping our body healthy.

Food is obtained from both plants and animals. Grains, fruits, vegetables, pulses, and edible oils come from plants, while milk, eggs, meat, fish, and honey are obtained from animals. A healthy diet includes a variety of foods from both sources to meet the body’s nutritional needs.

Food Sources and Eating Habits

Different living organisms have different food habits. Herbivores eat only plants, carnivores eat only animals, omnivores eat both plants and animals, and insectivores mainly feed on insects.

Humans also consume different edible parts of plants such as roots, stems, leaves, flowers, fruits, and seeds. Understanding food sources helps us appreciate biodiversity and the importance of agriculture.

Nutrients and Their Functions

Food contains several essential nutrients that perform different functions in the body. Carbohydrates and fats provide energy for daily activities, while proteins help in growth and repair of body tissues.

Vitamins protect the body from diseases and support healthy body functions. Minerals help build strong bones, healthy blood, and proper body development. Roughage improves digestion, and water helps transport nutrients, regulate body temperature, and remove waste products.

A balanced intake of all these nutrients is necessary for good health.

Vitamins, Minerals, and Deficiency Diseases

Each vitamin performs a special function in the body. Vitamin A supports healthy eyesight, Vitamin B helps the nervous system, Vitamin C strengthens immunity, Vitamin D builds strong bones, Vitamin E supports healthy skin and reproduction, and Vitamin K helps in blood clotting.

Important minerals include iron, calcium, iodine, and sodium. Their deficiency can lead to diseases such as anaemia, goitre, weak bones, and other health problems.

Students also learn about simple laboratory tests used to identify carbohydrates, proteins, and fats in different food items.

Balanced Diet and Healthy Eating

A balanced diet contains carbohydrates, proteins, fats, vitamins, minerals, roughage, and water in the right proportions. Eating a balanced diet helps maintain good health, supports growth, and prevents deficiency diseases.

Fresh fruits, vegetables, pulses, cereals, milk, and nuts should be included in the daily diet. Excessive consumption of junk food may lead to obesity and poor health because it contains high calories but very few essential nutrients.

Proper cooking methods, such as washing vegetables before cutting and avoiding excessive boiling, help preserve important nutrients.

Importance of Good Nutrition

Good nutrition keeps the body healthy, improves immunity, supports physical and mental growth, and provides energy for learning, playing, and daily activities. Healthy eating habits developed during childhood contribute to lifelong health and well-being.

Practice Questions

1. Name the major nutrients found in food.
2. What is a balanced diet?
3. Differentiate between herbivores, carnivores, and omnivores.
4. What are deficiency diseases? Give two examples.
5. Why should we avoid eating excessive junk food?

Answer Key

ANSWER 1

The major nutrients are carbohydrates, proteins, fats, vitamins, minerals, roughage, and water.

ANSWER 2

A balanced diet contains all the essential nutrients, roughage, and water in the correct proportions required for healthy growth and proper body functioning.

ANSWER 3

Herbivores eat only plants, carnivores eat only animals, while omnivores eat both plants and animals.

ANSWER 4

Deficiency diseases are illnesses caused by the lack of essential nutrients. Examples include scurvy caused by Vitamin C deficiency and rickets caused by Vitamin D deficiency.

ANSWER 5

Excessive junk food should be avoided because it contains large amounts of fat, sugar, and salt but very few essential nutrients, increasing the risk of obesity and other health problems.