Fiber Intake May Mitigate Heart Disease Risk for Shift Workers
A long-term study suggests that the dietary habits of shift workers, particularly their fiber intake, may influence their risk of coronary heart disease (CHD). This research proposes a potential dietary strategy to mitigate cardiovascular strain associated with night work.
Background
Night shift work disrupts the body's natural sleep-wake cycles, hindering repair and recovery processes. The cardiovascular system is sensitive to these disruptions, and consistent night shift work is correlated with an increased risk of cardiovascular disease (CVD), especially CHD. Prior research indicates that avoiding meat and increasing dietary fiber intake can prevent CVD.
Study Design and Participants
The study, published in the European Journal of Epidemiology, involved 222,801 participants with an average age of approximately 53 years. Participants were categorized into three groups:
- Daytime workers (83.6%)
- Shift workers with few or no night shifts (13%)
- Night shift workers (3.3%)
Dietary habits were assessed using questionnaires, and cardiovascular events were monitored over a median follow-up period of 12.6 years.
Key Findings
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Night shift workers exhibited a 10% higher CHD hazard compared to daytime workers. Shift workers with few or no night shifts did not show a significant difference from daytime workers after adjusting for various factors.
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Lower daily fiber intake was associated with a higher CHD risk in both shift-work groups.
This association weakened with increased fiber consumption, indicating a statistically significant interaction between fiber intake and work schedule.
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Meat avoidance, defined as consuming no processed or unprocessed red meat, was linked to a 10.4% lower CHD risk overall. This association was independent of work schedule or fiber intake.
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To reduce their CHD risk to that of daytime workers, night shift workers would need to consume about 19 g/day of fiber, while shift workers with little or no night work would need approximately 15 g/day.
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No sex-specific differences in CHD risk were found across work schedules.
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The researchers noted that higher fiber intake attenuated CHD hazard, particularly in night shift workers, possibly reflecting their increased baseline cardiovascular stress from factors like elevated blood pressure, inflammation, and circadian disruption.
Limitations and Considerations
The study identified several limitations:
- Dietary habits were assessed only at baseline.
- Potential for residual confounding from unmeasured lifestyle factors, such as night eating.
- Findings may have limited generalizability as the cohort consisted primarily of middle-aged adults.
Researchers also cautioned that increased fiber intake might not be suitable for all individuals and does not replace other cardiovascular protective measures like physical exercise, good sleep hygiene, and avoiding smoking.
Conclusion
This study highlights an interaction between dietary fiber intake and night shift work concerning CHD risk in middle-aged adults. It suggests that higher daily fiber intake may help mitigate the elevated CHD risks associated with night shift work.
The findings indicate a potential for tailored dietary plans for night shift workers, complementing existing cardiovascular health recommendations like the AHA’s Life’s Essential 8.