Trying to get enough sleep while working the late shift can feel like trying to swim upstream. Simply put, the human body is meant to be active during the daytime hours. In fact, humans' circadian rhythms (the body's biological sleep clock) are naturally programmed to promote sleep at night. Those who work at night and sleep during the day are fighting what their bodies naturally want to do.

Disrupting your circadian rhythm can lead to serious health problems, including an increased risk of cancer, heartburn, and ulcers, according to the International Agency for Research on Cancer (IARC), part of the World Health Organization. Here, five health risks that are more likely to occur in nighttime workers, and tips on how to stay as healthy as possible.

1. Increased Occurrence of Cancer.

In 2007, the IARC added overnight shift work to its list of probable carcinogens. Late-shift work disrupts the body's production of the hormone melatonin, a powerful antioxidant that, among other things, helps produce natural cancer-fighting cells. Darkness signals the body to produce melatonin. Late-shift workers are exposed to almost 24 hours of light, whether natural or artificial, meaning their bodies don't produce the melatonin needed for beneficial antioxidant activity.

2. Fatigue and Sleep Deficits.

Workers who are forced to sleep during the day often experience difficulties because their internal clocks don't adjust completely. Because they are more prone to disturbance, late-shift workers see a decrease in the duration and quality of their resting hours. Sleep deficit and fatigue can build up and even increase the possibility of accidents. According to Circadian Technologies, a consulting firm that helps companies adjust to working around the clock, graveyard-shift workers make five times as many serious mistakes and are 20 percent more likely to suffer severe accidents.

3. Gastrointestinal Disorders.

Eating healthfully on a night schedule is more difficult than during the day. Often, there are few options for meals other than fast food or vending machine snacks. Working opposite hours also makes it difficult to eat meals in their traditional order. Late-shift workers have been shown to be more likely to have heartburn, indigestion, diarrhea, and ulcers.

4. Stress.

The increased stress suffered by late-shift workers may be caused by many factors. Those working at night have less time to spend with family and friends. This lack of socialization may lead to tensions that, in turn, may cause anxiety, depression, and high blood pressure.

5. Women's Health Problems.

In addition to the above problems, women are at a greater risk for other specific health concerns. Studies have linked late-shift work to irregular menstrual cycles. Pregnant women who work at night have an increased risk of miscarriage, pre-term delivery, delivering low-birth weight babies, and delayed fetal development.

Adjusting to the Late Shift

Our economy may function on a 24/7 schedule, but our bodies don't. Listen to your body and do your best to give it what it needs. The IARC offers the following tips to the nearly 8 million Americans work the night shift:

  • Pack your own healthy meals. Try to eat lightly throughout your shift and then enjoy a moderate breakfast on your lunch break.
  • Pay close attention to physical fitness; a regular exercise program may help your body adjust to the negative effects of late-night work and can also help improve the quality and quantity of sleep.
  • Plan activities with your family in advance when possible. Spending your days off with your family will let them know they're important to you and will allow you social opportunities.
  • Make your bedroom as cool and dark as possible. Wear an eye mask and earplugs while sleeping to block out light and daytime noises. Try to sleep on a set schedule, which will help establish a routine and make sleeping during the day easier.
  • Aim to have at least one meal with your family each day. Eating together will encourage good eating habits and good communication.