How do meal times affect the health of night shift workers?

A new study has revealed that meal timing may significantly affect the health of night shift workers, increasing their risk of chronic conditions such as diabetes and heart disease.

Published in the journal Diabetologia, the research suggests that eating overnight could be detrimental to workers who maintain non-traditional hours.

"We know shift workers are more likely to have diabetes, they're more likely to have heart disease, and they're more likely to be overweight. Our research suggests that meal timing could be a major contributor to those issues," said Prof. Leonie Heilbronn from SAHMRI and the University of Adelaide in a statement.

Meal timing experiment

The study gathered 55 healthy adults who do not work night shifts and kept them awake for four nights and made them sleep during the day. They were divided into three groups: one that fasted overnight, one that consumed snacks, and another that ate full meals during the night shift.

"We found that blood glucose skyrocketed for those who ate full meals at night and those who snacked, while the people who fasted at night showed an increase in insulin secretion which kept blood sugar levels balanced," Heilbronn said.

Insulin sensitivity was disrupted in all participants, suggesting that night shifts contribute to circadian misalignment and impair glucose metabolism, according to the report.

"When you eat a meal, your body secretes insulin, and that insulin helps your muscles and other tissues to take up glucose. If you become resistant to insulin, then you can't take up that glucose as effectively into your muscles and if it continues, that potentially puts you at risk of diabetes," Heilbronn said.

Improving health outcomes for night workers

To improve health outcomes for employees, Prof. Siobhan Banks of the University of South Australia said not eating large meals while working the night shift and instead eating primarily during the day could be a straightforward intervention.

"This could be easier for people to follow than other, more complex diets," Banks said.

The researchers also plan to investigate the effects of protein snacks consumed during night shifts, aiming to determine if this could help mitigate hunger without negatively impacting health.