Health & Disease (AQA GCSE Combined Science: Synergy: Life & Environmental Sciences): Revision Note

Definition of health

• Health is defined as:

A state of physical, mental and social well-being' and not merely the absence of disease. Factors including diet, stress and life situations can affect both physical and mental health.

Factors affecting health:

• Diseases, both communicable and non-communicable, are major causes of ill health; ill-health affects not only the sufferer but their family members and the contribution that individual can make to society

  • Ill health can lead to a poorer quality of life or a reduced lifespan

  • The cost of an individual being ill - individuals who are sick may not be able to work and may require expensive healthcare (with the cost being attributed to the individual or a healthcare provider such as the NHS in the UK)

• Factors including diet, stress and life situations may have a profound effect on both physical and mental health

  • Eating a balanced diet that provides the right amount of energy and nutrients helps maintain good health, whereas a poor diet can lead to deficiencies, obesity, diabetes and poor mental health

  • Constantly being under stress can lead to cardiovascular issues (such as high blood pressure, increasing the risk of CHD) and poor mental health

  • Where a person lives and their income can have a profound impact on health - this affects the standard of healthcare that is accessible to them (and what they can afford), what food they buy, etc.

Communicable & Non-Communicable Diseases

• A disease is an illness or disorder of the body or mind that leads to poor health

  • they stop part of the body from working properly

• Each disease is associated with a set of signs and symptoms

Communicable diseases

• Pathogens cause communicable diseases which means they transfer from a diseased host to a healthy organism during infection, in other words the disease is infectious

  • Pathogens can infect plants as well as animals

• Communicable diseases can be spread by direct contact, water or air

• Examples of such diseases include:

  • tuberculosis

  • athletes foot

  • malaria

  • cholera

Non-communicable diseases

• Non-communicable diseases are non infectious diseases such as

  • cancer

  • heart disease

  • diabetes

• These diseases are the leading cause of death globally