Injuries and Illness

Facts About Shiftwork Health Problems

Shiftworkers are at greater risk for health problems than dayworkers. Two of those problems involve the cardiovascular system and the gastrointestinal system.

Cardiovascular problems can arise as a result of shiftwork because heart rate and blood pressure follow circadian rhythms, which are upset by the nighttime schedule. Circadian rhythm is the body’s 24-hour cycle, and it regulates many of the body’s functions.

When it comes to cardiovascular health, upsetting this natural rhythm can, over time, have seriously negative effects.

Normally, heart rate and blood pressure are lower at night and increase during the day. If an employee is working at night, however, blood pressure and heart rate stay high at night, too, because of the body’s activity.

It’s more difficult to get good, sound sleep during the day when body functions are awake. This means the cardiovascular system has trouble getting into a regular pattern of activity and rest. This can increase the risk of cardiovascular disorders.

Additionally, medical studies show that rotating shiftworkers and nightshift workers have increased levels of triglycerides and glucose, which may contribute to coronary disease. Poor eating habits and lack of sleep that often go along with shiftwork also contribute to cardiovascular disorders.


No time to write safety meeting materials? You don’t need to with the 50 prewritten safety meeting modules in BLR’s Safety Meeting Repros program. All meetings are ready to use, right out of the box. Try it completely at our expense! PLUS get a free report! Get the details.


It’s important to note, however, that shiftwork is not absolutely associated with cardiovascular disease. No one’s saying that because an employee work shifts that he or she is going to have a heart attack 10 years from now.

On the other hand, studies have also shown that men with a history of heart attack were more likely to have been shiftworkers than those with no history of heart attack.

Night Work and Stomach Ache

Do your shiftworkers ever complain that working a late shift upsets their stomachs? If so, they’re probably not imagining it.

Shiftworkers sometimes experience gastrointestinal disorders because food is not well digested at night. Following the body’s natural 24-hour cycle, a worker’s digestive system slows down at night and is active during normal daytime eating hours.

The digestive system is most active in the morning, around noon, and in the early evening. That’s why most people eat breakfast, lunch, and dinner at those times.

Eating when the digestive system isn’t very active can cause indigestion, heartburn, stomach aches, and loss of appetite. So if shiftworkers stomachs are aching, there could be a very easy explanation—the timing of their meals due to their work schedule.

Furthermore, shiftworkers may be more likely to eat prepared foods that are easy to microwave or foods from late-night fast food restaurants. These foods are often greasy, heavy, and difficult to digest. They may not provide very good nutrition either.


Examine Safety Meeting Repros completely at our expense. Send no money. Take no risk. Get a FREE report. Get more info.


Snacks Don’t Help Either

Snacking on sugary or fatty junk food from the vending machine is another common shiftwork health problem.

Candy bars, cookies, and so on may give you a temporary burst of energy, but it only lasts a short time. Once the body has adjusted to the higher energy level and the sugar high wears off, a person’s energy level actually drops below what it was before the snack.

Finally, carbonated drinks such as cola are often consumed by shiftworkers for their caffeine content. But while the caffeine might help keep a shiftworker awake, the carbonation can irritate the stomach and cause indigestion and heartburn.

Tomorrow, more about circadian rhythms and the health and safety affects of shiftwork.

Print