A combination of a balanced diet and regular exercise is needed to help keep the body healthy.
Our bodies provide an excellent environment for many microbes which can make us ill once they are inside us.
Our bodies need to stop most microbes getting in and deal with any microbes which do get in.
Vaccination can be used to prevent infection
B1.1 Diet and Exercise
(a) A healthy diet contains the right balance of the different foods you need and the right amount of energy.
Carbohydrates, fats and proteins are used by the body to release energy and to build cells.
Mineral ions and vitamins are needed in small amounts for healthy functioning of the body.
A person is malnourished if their diet is not balanced.
This may lead to a person being overweight or underweight.
An unbalanced diet may also lead to deficiency diseases or conditions such as Type 2 diabetes.
A person loses mass when the energy content of the food taken in is less than the amount of energy expended by the body. Exercise increases the amount of energy expended by the body.
The rate at which all the chemical reactions in the cells of the body are carried out (the metabolic rate) varies with the amount of activity you do and the proportion of muscle to fat in your body.
Metabolic rate may be affected by inherited factors.
(d) Inherited factors also affect our health; for example cholesterol level.
(e) People who exercise regularly are usually healthier than people who take little exercise.