Carbohydrates and fats are needed to provide energy for your body chemistry to function correctly and to keep you warm at 37oC.
Proteins are used by the body to build cells - growth of new tissue, cell repair and cell replacement.
Mineral ions and vitamins are needed in small amounts for healthy functioning of the body - organs, skin, bones etc.
Fibre keeps everything moving smoothly through your digestive system.
A person is malnourished if their diet is not balanced.
Lack of a good healthy diet can cause a person to be overweight or underweight.
An unbalanced diet may also lead to deficiency diseases or conditions such as Type 2 diabetes.
People who live on a poorly balanced diet are malnourished and malnourishment is common in the poorer developing countries of the world e.g. in Africa.
You need energy to fuel the chemical reactions in your body to keep you alive and these reactions are called your metabolism.
People who exercise regularly are usually healthier than people who take little exerciseDiet and Exercise
Diet and Exercise
Microorganisms that cause infectious disease are called pathogens.
Bacteria and viruses may reproduce rapidly inside the body and may produce poisons (toxins) that make us feel ill.
Bacteria are very small cells which can rapidly reproduce in your body making you feel ill by damaging your body's cells and producing toxinsViruses & bacteria
Viruses & bacteria
Viruses are NOT cells and much smaller than bacteria and damage the cells in which they reproduce.
White blood cells help to defend against pathogens by: 1. Engulfing it; 2. Producing Anti-Bodies; 3. Producing Anti-Toxins
The immune system of the body produces specific antibodies to kill a particular pathogen.
Antibiotics cannot be used to kill viral pathogens, which live and reproduce inside cells.