Lifestyle & Non-Communicable Diseases | Biology for Grade 10 PDF Download

Risk Factors

• Risk factors are linked to an increased rate of a disease; but exposure to a risk factor doesn’t guarantee that an individual will suffer a disease (a person who smokes regularly isn’t guaranteed to develop lung cancer but their risk compared to someone who doesn’t smoke is much, much higher)
• Certain risk factors correlate with certain diseases (are related to them); but correlations are not always causations
• Risk factors can be:
  • Aspects of a person’s lifestyle; such as the food they eat or whether or not they drink alcohol
  • Substances in the person’s body or environment; such as air pollution in a crowded city or asbestos in old buildings

Causal Mechanisms & Risk Factors

• A causal mechanism has been proven for some risk factors, but not in others
  Risk factors & causal mechanisms table
  
• Many diseases are caused by the interaction of a number of factors; the chance of developing cardiovascular disease is higher in individuals who have a poor diet high in cholesterol (fat), don’t exercise regularly and smoke – because all of these behaviours increase the likelihood of damage occurring to the arteries

Sampling, Translating & Interpreting Data

• Sampling allows researchers to infer (deduce/conclude) information about a population without having to investigate every individual which would be time-consuming and essentially impossible to do accurately
• Scientists sample populations to determine risk factors for different diseases and inform public health policy
  • For example; sampling individuals with type 2 diabetes and identifying patterns or similarities in their lifestyle and health condition allows scientists to deduce that obesity and a diet high in sugar and fat are risk factors for developing this condition (as these factors are found in most individuals who develop type 2 diabetes)
• Scientists present their findings in graphical and numerical forms top identify if there are relationships between risk factors and certain disease
• Scatter diagrams are used to identify correlations between two variables to determine if a factor (such as obesity) does increase the risk of developing a disease (such as type 2 diabetes)

Exam Tip: You should be able to translate information between graphical and numerical forms and extract and interpret information from charts, graphs and tables to determine risk factors.

Applications of Non-Communicable Diseases

• Lifestyle factors such as diet, alcohol consumption and choosing to smoke have a big impact on the incidence of non-communicable diseases at all levels in society (from the individual to national and globally)
• Poor lifestyle factors such as those mentioned above increase the likelihood of individuals within a population suffering from non-communicable disease
  • Remember a non-communicable disease is not caused by a pathogen and tends to have more longer-lasting effects on the health of an individual (usually they get progressively worse over time)

Smoking as an example

• An individual who smokes cigarettes is far more likely to suffer lung cancer than an individual who doesn’t
• Treatment for cancer includes surgery, radiotherapy and chemotherapy – all of these require hospitalisation and access to the right medication
• Hospitalisation utilises healthcare capacity and medicinal drugs – costing time and money at both a local and national level (and a personal level if healthcare is self-funded)
• The individual with lung cancer may not be able to work whilst receiving treatment, this reduces their income and loss of work can have a profound effect on mental health
• Nationally; the inability of individuals to work can affect a countries economy
• A causal mechanism has been proven for some risk factors, but not in others

Exam Tip: You should be able to discuss the human and financial cost of non-communicable diseases (such as cancer or CHD) at an individual, a local community, a national and a global level.