Working a nonstandard schedule — such as night shifts, split shifts or rotating shifts — immediately affects your life. It impacts how and when you eat, sleep, exercise and maintain relationships.
But the side effects of unusual work patterns may continue even after you resume a standard schedule or retire. Shift work can influence your health throughout adulthood. The good news is that there are steps you can take and community resources that can steer you toward a healthier future.
Long-term impact of shift work on health and well-being
The biggest health challenge facing shift workers is the interruption of circadian rhythm — your body’s physical, mental and behavioral processes that follow a 24-hour cycle. Circadian rhythms are influenced mainly by light and darkness. Shift work — especially at night — often disturbs the body’s systems regulated by circadian rhythm, including the sleep/wake cycle.
The more years you work a shift schedule, the higher your risk of chronic health issues. It doesn’t matter whether you work a night shift or rotating shifts — any shift work can lead to chronic medical conditions, such as:
1. Cancer
A circadian rhythm that’s off balance affects your cellular function. It can interfere with DNA repair, cell cycles and cell death. The National Toxicology Program reports that ongoing disruptions in circadian rhythm may eventually lead to cancer.
Even if you do get enough sleep, the reversal of light and dark that shift workers experience can affect your production and release of melatonin, a hormone that helps you fall asleep faster and sleep more deeply. When cells don’t function as they should and don’t get repaired during deep sleep, DNA damage accumulates, tumors don’t get suppressed and cancer can progress more easily.
2. Cardiovascular disease
Working a longer or nonstandard schedule may put you at higher risk for heart disease and stroke. One study found the risk of death from all causes and cardiovascular disease is higher in women who’ve worked rotating night shifts for five or more years compared to women who never worked night shifts.
Experts associate shift workers’ higher risk of cardiovascular disease with:
- Chronic stress caused by maintaining a nonstandard schedule
- High blood pressure, which is linked to working longer hours
- Increased metabolic risk factors including high body mass index (BMI) and smoking
3. Gastrointestinal disorders
People who work rotating shifts are more likely to experience:
Gut dysfunction can result from sleep deprivation associated with shift work. What you eat as a shift worker can also increase your risk for long-term gastrointestinal disease. Many shift workers eat the same number of calories as non-shift workers. But their diet is more likely to include processed food, whose additives can alter the gut microbiome.
4. Mental health disorders
Working a nonstandard schedule makes it hard to maintain relationships and can be isolating. People who work overnight or inconsistent hours are also more likely to experience stress and psychological difficulty than people who work standard daytime schedules.
In a study of more than 175,000 people, researchers found shift work to be associated with a higher risk of developing depression and anxiety — the higher the shift frequency, the higher the risk.
5. Metabolic disorders such as obesity, metabolic syndrome and Type 2 diabetes
Metabolic disorders are conditions that develop from a disrupted metabolism (the process of converting food to energy). Shift work that alters your circadian rhythm can disrupt the balance of your hormones, which guide your metabolism.
Shift work increases your risk for metabolic disorders because it’s associated with:
- Higher BMI than day-shift workers
- Hormonal imbalance, which affects your appetite, food intake and body weight
- Unhealthy lifestyle choices about smoking, diet and exercise
Warning signs of work-related sleep disorders
According to research, night-shift workers are three times more likely to suffer from a shift-related sleep disorder than people who work a day shift. Recognizing the signs and getting treatment for a sleep disorder may help you avoid associated physical and mental health issues.
People with a work-related sleep disorder may experience:
- Daytime sleepiness, which is a symptom of shift work sleep disorder — a circadian rhythm sleep disorder
- Difficulty falling or staying asleep (insomnia), which can be a sign of shift work sleep disorder
- Irregular sleep patterns, including falling asleep at odd times, which can also indicate narcolepsy — a sleep disorder that causes excessive sleepiness
- Snoring or interrupted sleep, which are also sleep apnea symptoms that tend to be worse for shift workers.
If you notice your symptoms don’t go away or get worse, consult your primary care physician. They can provide treatment options or direct you to the appropriate provider and care.
Tips for managing the long-term impacts of shift work
Maintaining healthy lifestyle habits and getting the support you need can reduce your risk for chronic conditions associated with shift work.
As a shift worker, focus on:
- Eating habits: Eat high-quality, whole food whenever possible. The Centers for Disease Control and Prevention (CDC) recommends not eating between midnight and 6 a.m. to maintain typical eating patterns.
- Sleeping better: Adopt sleep strategies designed for shift workers that align with your individual needs, work schedule and home environment.
- Maintaining relationships: Eat at least one meal with your family daily. Schedule time weekly to catch up with friends, either in person or by video chat.
- Seek help and resources: Many organizations and services, such as shift workers’ associations, employee assistance programs and sleep education websites, offer support for shift workers. UCLA Health provides comprehensive care for sleep disorders.
