Food, Nutrition, Health and Fitness | Class 11 Home Science Notes

Definitions of Food, Nutrition, Nutrients, Health and Fitness

Food is defined as any solid or liquid substance that, when swallowed, digested, and assimilated, supplies the body with essential substances called nutrients, which are vital for maintaining health. Food provides energy, supports growth and repair of tissues, protects the body from disease, and regulates bodily functions. Nutrition is the comprehensive science that studies foods, the nutrients they contain, and their actions within the body, including ingestion, digestion, absorption, metabolism, and excretion. It also considers social, psychological, and economic factors influencing nutrition. Nutrients are the chemical constituents in foods that must be supplied in adequate amounts to maintain health. These include macronutrients such as carbohydrates, proteins, and fats, and micronutrients such as vitamins and minerals, along with water and fibre. Most foods contain multiple nutrients; for example, milk contains proteins and fats. Nutrients are classified based on the quantity required: macronutrients are needed in large amounts daily, while micronutrients are required in smaller quantities. Health, as defined by the World Health Organization (WHO), is a state of complete physical, emotional, and social well-being, not merely the absence of disease or infirmity. Fitness refers to the body's ability to function efficiently and effectively in work and leisure activities, resist diseases, and meet emergency situations. Physical fitness includes aerobic fitness, muscular strength, muscular endurance, flexibility, and body composition. A well-nourished and fit individual has better energy, stamina, and self-esteem, which are essential for learning and overall well-being.

📊 Diagram: Figure 1 (img-1.jpeg) illustrates the classification of nutrients into macronutrients and micronutrients, showing examples of each nutrient group and their roles in the body.

🔗 Connection: Prepares the learner to understand the concept of a balanced diet and the role of nutrients in health and fitness.