Health and Disease
Healthy
Health is a state of physical and mental well-being, not just an absence of disease:
Balanced Diet
Exercise
Positive Mental Health
Good Lifestyle Choices
Regular Check Ups
Clean and Hygienic
Supportive Environment
Unhealthy
Disproportionate Diet
Lazy
Stressed/ Anxious/ Depressed
Smoking/ Drugs/ Alcohol
No Check Ups
Weak Immune System
Types of Diseases
Communicable – caused by pathogens: bacteria and viruses. They are contagious e.g. ebola,
chicken pox and cholera.
Chronic – means that it is present either continuously or on and off over a long period of
time e.g. fatigue, arthritis and IBV.
Conginental – disorders that are present when a baby is born e.g. down syndrome and
foetal alcohol syndrome.
Non-Communicable – cannot be transported from one to another e.g. cancer, eczema and
IBS.
Degenerative – a disease that causes breakdown of body cells, tissues and organs as it
processes e.g. multiple sclerosis and alzheimers.
Diseases can be caused by:
- food
- weight
- exercise
- sleep
, - stress
- drugs
- tobacco
- alcohol
- heredity
- age
- gender
- environment
Drugs
Drugs are substances that cause change in the body. Some can help, others can harm. Drugs
are usually extracted from natural sources and modified by chemists. New medical drugs
have to be tested to ensure they work and are safe. The testing process is:
1. Scientists study bodies and diseases to see how they work. They try to find targets for
medicines to work at. These targets are things that cause diseases such as tiny protein
molecules.
2. Computers and cell samples are used to find chemicals that seem to work on the targets,
1000s of chemicals are tested like this.
3. The most promising treatments are used to see how much is poisonous. Scientists need
to know how quickly and where the body absorbs the chemical and how quickly it flushes
out. Small mammals are used in this testing stage.
4. The first clinical trial is where new medicines are tested on healthy people, to make sure
there are no unexpected side effects.
5. The second clinical trial involves a much bigger group of patients to see if the drugs work
on the disease it’s designed for.
6. Double blind randomisation trials involve large numbers of patients. Some are given the
medicine, others a placebo. No one knows what they are taking to avoid bias.
7. If a medicine passes all the clinical trials it can get a licence from the government which
means doctors can use it.
8. Doctors prescribe licensed medicines but continue to monitor the effects on patients, this
is Phase 4, clinical trial.
Key Terms
Control Group – We use a control group so that improvements due to the treatment are
compared with improvements in a group which either receive a placebo or an already
widely used treatment. This comparison makes it less likely that any benefits are due to any
factors other than the drug.
Healthy
Health is a state of physical and mental well-being, not just an absence of disease:
Balanced Diet
Exercise
Positive Mental Health
Good Lifestyle Choices
Regular Check Ups
Clean and Hygienic
Supportive Environment
Unhealthy
Disproportionate Diet
Lazy
Stressed/ Anxious/ Depressed
Smoking/ Drugs/ Alcohol
No Check Ups
Weak Immune System
Types of Diseases
Communicable – caused by pathogens: bacteria and viruses. They are contagious e.g. ebola,
chicken pox and cholera.
Chronic – means that it is present either continuously or on and off over a long period of
time e.g. fatigue, arthritis and IBV.
Conginental – disorders that are present when a baby is born e.g. down syndrome and
foetal alcohol syndrome.
Non-Communicable – cannot be transported from one to another e.g. cancer, eczema and
IBS.
Degenerative – a disease that causes breakdown of body cells, tissues and organs as it
processes e.g. multiple sclerosis and alzheimers.
Diseases can be caused by:
- food
- weight
- exercise
- sleep
, - stress
- drugs
- tobacco
- alcohol
- heredity
- age
- gender
- environment
Drugs
Drugs are substances that cause change in the body. Some can help, others can harm. Drugs
are usually extracted from natural sources and modified by chemists. New medical drugs
have to be tested to ensure they work and are safe. The testing process is:
1. Scientists study bodies and diseases to see how they work. They try to find targets for
medicines to work at. These targets are things that cause diseases such as tiny protein
molecules.
2. Computers and cell samples are used to find chemicals that seem to work on the targets,
1000s of chemicals are tested like this.
3. The most promising treatments are used to see how much is poisonous. Scientists need
to know how quickly and where the body absorbs the chemical and how quickly it flushes
out. Small mammals are used in this testing stage.
4. The first clinical trial is where new medicines are tested on healthy people, to make sure
there are no unexpected side effects.
5. The second clinical trial involves a much bigger group of patients to see if the drugs work
on the disease it’s designed for.
6. Double blind randomisation trials involve large numbers of patients. Some are given the
medicine, others a placebo. No one knows what they are taking to avoid bias.
7. If a medicine passes all the clinical trials it can get a licence from the government which
means doctors can use it.
8. Doctors prescribe licensed medicines but continue to monitor the effects on patients, this
is Phase 4, clinical trial.
Key Terms
Control Group – We use a control group so that improvements due to the treatment are
compared with improvements in a group which either receive a placebo or an already
widely used treatment. This comparison makes it less likely that any benefits are due to any
factors other than the drug.
