· Excessive workload
· Physical illness
· Excessive physical exercise
· Financial pressures
· Lack of sleep
· Excessive caffeine intake
· Smoking and social drug use
· Excessive alcohol consumption
· Emotional distress form a relationship
· Excessive workload
· Physical illness
· Excessive physical exercise
· Financial pressures
· Lack of sleep
· Excessive caffeine intake
· Smoking and social drug use
· Excessive alcohol consumption
· Emotional distress form a relationship