Good nutrition creates health in all areas of our existence. T. Colin Campbell 5.4 NUTRITION 86 A kilocalorie is the amount of heat needed to raise the temperature of 1 kg of distilled water from 14.5°C to 15.5°C at a pressure of 1 atmosphere. Dehydration is a condition that occurs when the body loses more water than it takes in, leading to an imbalance that affects normal functions. It can result from excessive sweating, inadequate water intake, illness (such as vomiting or diarrhoea), or prolonged exposure to heat. THE BASICS OF NUTRITION The body needs energy to perform various activities and to ensure the vital functions necessary for survival. The source of this energy is food. Food consists of complex substances that the body, through digestion, transforms into simpler substances that it uses as fuel. Nutrients Nutrients proteins, carbohydrates, lipids, vitamins, water, and minerals provide energy, support muscle growth, prevent deficiency diseases, supply essential minerals, and help distribute fluids throughout the body. They contribute to three fundamental functions: energy function, supplying the energy needed for the body s activities; the unit of measurement for energy is the kilocalorie (kcal) ; structural function, renewing cells and tissues and enabling the body s growth; ONLINE RESOURCES Different types of diet styles Carbohydrates Proteins 164 SCIENCE AND PHYSICS regulatory function, ensuring the proper execution of all biological processes within the body. Lipids Vitamins Minerals Water A diet is considered balanced when it includes foods that provide all the necessary nutrients in the right amounts to allow the body to perform its functions. A poor diet, both in terms of quality and quantity, makes our body more vulnerable to diseases. Water Even though water does not provide energy, it is essential for survival and is the most important among the inorganic components of our body. In adults, it accounts for about 65% of body weight, while in children it reaches up to 75%. Water: is one of the main components of blood; helps maintain thermal balance (through perspiration); enables the digestion, absorption, and transportation of nutrients, as well as the elimination of waste substances (through urine and sweat). Humans need approximately 35 grams of water per day for every kilogram of body weight, as water balance is regulated by the amount of water ingested and produced in the body, which must be the same as the amount expelled . Water is obtained both by drinking and through foods that contain high amounts of it (e.g. meat contains 55-70%, vegetables 75-85%, and fruit 80-92%). perspiration: traspirazione to supply: fornire waste: scarto