Understanding Nutrition and Metabolism: Essential Concepts for Health

Nutrition: The Foundation of Health

1.1 Definition

Nutrition is the study of foods and their impact on our growth and well-being. It encompasses the behaviors and social factors that influence our food choices.

Foods provide us with energy (calories) and essential nutrients such as protein, fat, carbohydrates, vitamins, minerals, and water. Consuming a balanced diet provides the energy we need for daily activities, helps maintain a healthy weight, and reduces the risk of chronic diseases like diabetes and heart disease.

Metabolism: The Body's Energy Engine

2.1 Definition

Metabolism refers to the chemical processes that occur within living cells and organisms to sustain life. These processes involve breaking down substances to release energy and synthesizing new substances.

Metabolism encompasses all the activities that occur within the body to maintain and build tissues, generate energy, and ensure overall health.

Metabolic Equivalent of Task (MET)

2.5 Definition

The metabolic equivalent of task (MET) is a physiological measure that expresses the energy cost of physical activities. One MET is equivalent to the energy expended while sitting at rest.

During exercise, the MET value indicates the intensity of the activity compared to rest. An activity with a MET value of 5 means it requires five times the energy expenditure of resting.

Carbohydrates: Our Primary Energy Source

1.3.1 Types of Carbohydrates

• Simple carbohydrates: Sugary foods like cakes and biscuits
• Complex carbohydrates: Starchy foods like potatoes, rice, and pasta

Complex carbohydrates should be consumed in greater quantities than simple carbohydrates.

In the stomach, complex carbohydrates are broken down into simple carbohydrates (such as glucose and fructose). Some of these are used for immediate energy, while others are stored in the liver and muscles as glycogen.

Carbohydrates should constitute approximately 55% of our daily diet. One gram of carbohydrates provides 4 kilocalories (Kcal) of energy.