Shift work, particularly that involving overnight hours, can negatively affect anyone. However, people living with type 2 diabetes are at an increased risk of health complications because irregular working hours make blood sugar management more difficult.

According to the Bureau of Labor Statistics, in 2017–2018, 16% of workers held a non-daytime schedule. Of these individuals, 6% worked in the evening, 4% worked overnight, and the remaining 6% had a variable shift pattern.

In this article, we look at how shift work can affect people living with type 2 diabetes. We also explain what steps a person can take to mitigate the effects.

A 2017 study on how shift work affects people living with type 2 diabetes found that the participants who worked the night shift had a more difficult time managing their blood sugar levels than those who worked during the day or were unemployed.

The Endocrine Society discussed this study, noting that people who worked overnight reported additional issues, including:

  • higher body mass index (BMI)
  • shorter sleep duration
  • higher daily intake of calories

If a person does not control their blood sugar levels well, this can cause hypoglycemia, in which blood sugar levels are too low, or hyperglycemia, when they are too high.

According to the American Diabetes Association (ADA), the only way for a person to know for sure whether they are experiencing hypoglycemia is to check their blood sugar levels. However, certain symptoms can indicate low blood sugar. They might include:

  • shakiness, nervousness, or anxiousness
  • sweating, chills, or clamminess
  • lightheadedness or dizziness
  • weakness or sleepiness
  • clumsiness or issues with coordination
  • confusion
  • irritability or impatience
  • increased heartbeat
  • hunger or nausea
  • blurred or impaired vision
  • drained skin color
  • a headache
  • nightmares or sleep disruptions
  • seizures

Some people may not have any symptoms if their blood sugar is too high. Those who are symptomatic may experience:

  • dizziness
  • tiredness
  • frequent urination
  • listlessness
  • nausea
  • excessive thirst

A person with type 2 diabetes is more likely to experience high glucose levels than someone who does not live with diabetes. If hyperglycemia occurs regularly, they should talk to their doctor about changes in medication.

According to the ADA, poorly managed or untreated diabetes can result in various health complications, such as stroke, eye trouble, skin issues, and nerve problems.

In a recent study, researchers looked at how night shift work affected people living with type 2 diabetes. The findings showed that, in addition to impairing the management of blood sugar levels, working nights had an adverse effect on oral health.

Shift work may also put someone at higher risk of developing type 2 diabetes. In an older study, rotating night shift work correlated with increased body weight in females and slightly increased their overall risk of type 2 diabetes.

A newer study from 2019 had similar results. The researchers found that healthcare workers who worked overnight had a higher risk of developing metabolic conditions, such as type 2 diabetes and heart disease.

People living with type 2 diabetes and those at higher risk of developing the condition can take some steps to help reduce the negative effects that shift work has on their health.

The Endocrine Society suggest that a person working night or varying shifts should manage their type 2 diabetes by:

  • eating a healthful diet
  • taking all diabetes medication according to the prescription
  • engaging in regular exercise

The National Institute of Diabetes and Digestive and Kidney Diseases recommend that people work with a healthcare provider or dietitian to develop a healthful eating plan. Those living with diabetes should focus on eating a variety of foods from the main food groups, including:

  • grains
  • vegetables
  • dairy
  • fruits
  • protein

It is also important to count carbs or follow the plate method to get the right portion of each food group.

As working overnight can be challenging for eating well, the ADA advise people to pack their own homemade snacks and meals for each shift. By doing this, a person can avoid fast food or other purchased foods that may be less healthful.

The ADA also suggest that people with diabetes prepare for a night shift by:

  • checking their blood sugar as directed for basal-bolus insulin therapy
  • making connections with co-workers in case the need arises for a fast-acting glucose source or injection
  • exercising regularly
  • keeping an eye out for patterns that may develop to help with insulin dosing
  • developing a treatment plan that works with an off-hours schedule
  • avoiding caffeine from 4–6 hours before bedtime
  • checking blood sugar levels before bedtime
  • carrying insulin pens instead of syringes or vials
  • considering using an insulin pump and continuous glucose monitoring
  • taking walks during breaks
  • avoiding heavy meals before bedtime

Shift work can have an adverse effect on type 2 diabetes. It can also put a person at higher risk of developing type 2 diabetes in the first place. Shift work, particularly that involving overnight and varying shifts, can make it more difficult to manage glucose levels. Poor management of blood sugar levels can lead to additional health problems, including increased weight and oral health issues.

A person can take steps to prevent issues with their glucose levels overnight, including planning meals ahead of time, keeping up with exercise programs, and working with their healthcare provider to develop a diabetes management plan that suits their schedule.