Shift work is defined as any arrangement of daily working hours other than the standard daylight hours (7/8 a.m. – 5/6 p.m.).
Effects of shift work
Circadian rhythms are physical, mental and behavioral changes that follow an approximate 24-hour cycle and are enforced primarily by light and darkness cycles in the environment. Shift workers who experience disruption of the circadian system and altered sleep patterns probably have an elevated risk of breast cancer, and a potentially elevated risk of colorectal cancer.
Other negative effects of shift work include:
- Disorders of the gastrointestinal tract
- Disorders of the cardiovascular system
- Metabolic disturbances
- Increased workplace accidents associated with worker fatigue
- A negative impact on fetal growth in pregnant women resulting in low birth weight
- Anxiety and depression resulting from social isolation
Disruption in family or personal life
Strategies to counter the effects of shift work
Individuals who work shifts encounter a variety of issues resulting from a change in eating, sleeping and working patterns. Strategies that workers can adopt include:
- Employing a rapid shift rotation where workers work two or three days, then two or three nights, then have time off. This rotation both reduces the disruption to the circadian rhythm and allows the workers to maintain some aspects of their regular social interactions.
- Negotiate adequate rest periods for shift workers. Eliminate split shifts and nighttime work where possible (but also be careful about working alone).
- In the case of rotational shifts, have the shifts rotating forward from day to afternoon to night because circadian rhythms adjust better when moving forward than backward. Avoid having early morning shifts that start before 6 a.m.
- Have 20-30 minute naps while on breaks, especially during night shifts.
- Regular physical activity facilitates sleep and improves its quality. It also decreases the feeling of fatigue while increasing alertness, vigour and energy.
- High quality meals and snacks, while avoiding high fat, high carbohydrate, sugary and processed foods will prevent energy levels from dropping and minimize sleep cycle disruption.
- Limit the use of stimulants such as caffeine, nicotine and alcohol – especially before bedtime.
- Request that your employer have a dedicated rest area that is as dark and as quiet as possible.
The information above is limited. For much more, including broader strategies for dealing with shift work, check out the full-length fact sheet.