Daytime Meals Could Mitigate Night Shift Risks, Researchers Say

Night shift

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Key Takeaways

  • Shift work is often associated with significant health risks—including heart disease and cancer—because of disruptions in the body's metabolism.
  • A new, small clinical study suggests one way to lower risk would be for workers to eat during the day and refrain from eating at night.
  • It is possible this simple technique could have metabolic benefits, particularly for lowering diabetes risk.

Shift work has often been linked to a higher prevalence of health conditions like heart disease, diabetes, and cancer. But a new study in Science Advances suggests eating at different times could somewhat mitigate those risks.

About the Study

Researchers recruited 19 healthy young men and women and randomly assigned them to a 14-day protocol that simulated night work conditions. In one group, participants ate during the evening mimicking a meal schedule typical among overnight shift workers. The other group ate only during the daytime.

Frank Scheer, PhD

Meal timing could be used as a countermeasure against the negative effects of disrupted circadian rhythm, as well as impaired glucose tolerance.

— Frank Scheer, PhD

Those in the latter group had better-regulated glucose levels compared to those who ate at night, an indication that eating at night may impair your circadian rhythm. When your circadian rhythm is impaired it has a significant effect on your metabolism. Because shift workers are already in danger of circadian disruptions, the timing of their meals could be throwing that rhythm off even more.

"The takeaway is that meal timing could be used as a countermeasure against the negative effects of disrupted circadian rhythm, as well as impaired glucose tolerance," says study lead Frank A. J. L. Scheer, PhD, director of the medical chronobiology program at Brigham & Women's Hospital in Boston.

Although the recent trial is limited by its small number of participants, Dr. Scheer adds that the results are promising. More research on a larger pool of shift workers may lead to stronger recommendations for shift workers, he says.

Night Shift Effects

Defined as working outside of normal daylight hours of 7 a.m. to 6 p.m., shift work can involve working in the evenings, overnight, or on a particularly long shift that stretches well past 8 hours.

Shift work can include a breadth of jobs, such as working in a warehouse or completing industrial jobs. Police officers, healthcare providers, truck drivers, and firefighters also work shifts. In fact, the Bureau of Labor Statistics reports that about 15.5 million people in the U.S. can be defined as shift workers.

The need for more strategies to address the health concerns of these individuals is important, given the range of risks associated with shift work. In addition to cancer, diabetes, and heart disease, there are other conditions that can be connected to this type of work including obesity, high blood pressure, peptic ulcers, sleep disorders as well as mood disorders like depression and anxiety.

Variability in sleep, eating, and rest can be particularly tough on mental health. For example, a study in npj Digital Medicine on more than 2,000 interns in a physician training program found that those with variable sleep schedules were more likely to score higher on standardized depression symptom questionnaires and report lower daily mood ratings. This was similar to those who got fewer hours of sleep or stayed up late.

Bigger Problems

Some of the risks associated with shift work are likely connected to irregular eating times, but that is not the only factor at play, says Arne Lowden, PhD, at the Stress Research Institute at the University of Stockholm in Sweden.

Arne Lowden, PhD

There are many difficulties when it comes to dietary recommendations for shift workers. For example, eating at night might improve well-being but simultaneously impair metabolism.

— Arne Lowden, PhD

As a sleep and stress researcher who primarily studies shift workers, he says that diet quality and timing matter. Other factors also can play a part as well, including disrupted circadian rhythms, sleep debt, physical inactivity, insufficient time for rest, and psychosocial stress.

"There are many difficulties when it comes to dietary recommendations for shift workers," he says. "For example, eating at night might improve well-being but simultaneously impair metabolism. That said, there are some strategies that may be helpful."

Tactics that may lower shift work risks include:

  • Eating breakfast before day sleep to avoid waking up due to hunger
  • Sticking as closely as possible to a normal day and night pattern of food intake
  • Avoiding over-reliance on convenience foods, high-carbohydrate foods, and sugary treats during a shift
  • Getting regular exercise when not working
  • Maintaining good sleep hygiene as much as possible, such as creating a bedtime ritual even if you sleep during the day

Dr. Lowden adds that it is important for individuals to experiment with better strategies, but notes that employers also need to recognize the importance of these habits for a healthier workforce.

What This Means For You

Eating during the day may help mitigate some health risks for shift workers, and can be especially helpful with other tactics like choosing high-quality foods and getting enough physical activity. If you are a shift worker, talk to a healthcare provider or registered dietitian on how you can use meal timing to offset some job-related health risks.


4 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Chellappa SL, Qian J, Vujovic N, et al. Daytime eating prevents internal circadian misalignment and glucose intolerance in night workSci Adv. 2021;7(49):eabg9910. doi:10.1126/sciadv.abg9910

  2. U.S. Bureau of Labor Statistics. Job flexibilities and work schedules news release.

  3. Franciscan Health. Working night shift: The health effects.

  4. Fang Y, Forger DB, Frank E, Sen S, Goldstein C. Day-to-day variability in sleep parameters and depression risk: a prospective cohort study of training physiciansnpj Digit Med. 2021;4(1):28. doi:10.1038/s41746-021-00400-z

By Elizabeth Millard, CPT, RYT
Elizabeth Millard is a freelance journalist specializing in health, wellness, fitness, and nutrition.