NIGHT shift work can decimate your heart health make you more likely to develop two silent killer conditions – but switching up the timing of your meals may lower your risk.
The meal trick could protect from the increased risk of a or , researchers said.
Several previous studies have shown that working night shifts is associated with serious risks, including to the heart.
This is because working at night throws off people's – as well as their mealtimes.
Now, a new study shows that only eating during the daytime even when working nights could help people avoid the health risks associated with shift work.
It suggests that the timing of meals might be a bigger risk factor for than the time people fall into bed.
Study senior author Professor Frank Scheer, of Brigham and Women's Hospital in Boston, said: “Our prior research has shown that – the mistiming of our behavioural cycle relative to our internal body clock – increases cardiovascular risk factors.
“We wanted to understand what can be done to lower this risk, and our new research suggests could be that target.”
Animal studies have shown that aligning meals with the internal body clock could reduce the health risks of staying awake into the wee hours when we'd usually be sleeping.
This prompted Prof Scheer and his colleagues to test the concept in humans.
For the new study, published in the journal Nature Communications, researchers enlisted 20 healthy young participants to a two-week in-patient study at the Brigham and Women’s Center for Clinical Investigation that mimicked the conditions of night work.
Participants had no access to windows, , or electronics that would clue their body clocks into the time.
Researchers were able to determine what effect circadian misalignment had on them by comparing how their body functions changed from before to after simulated night work.
Participants followed a “constant routine protocol” and in a dimly lit environment, maintaining the same body posture and eating identical snacks every hour.
After that, they participated in simulated night work and were told to eat either during the night-time – as most night shift workers do – or only during the daytime.
Both groups had an identical nap schedule, so any differences between them were not due to differences in schedule.
The research team examined how food timing affected participants' cardiovascular health and how they changed after the simulated night work.
Researchers measured several cardiovascular risk factors, such as plasminogen activator inhibitor-1 – which increases the risk of – and .
They found that the cardiovascular risk factors increased after simulated night work in participants who ate during the day and night.
But for people who only ate during the daytime, their cardiovascular markers stayed the same.
The amount of food they ate and the content of their meals were no different to the first group – only the timing of their meals.
Study lead author Professor Sarah Chellappa, of the University of Southampton, added: “Our study controlled for every factor that you could imagine that could affect the results, so we can say that it's the food timing effect that is these changes in the cardiovascular risk factors.”
Researchers said more research with larger samples and using people who actually follow shift work schedules is needed to show the long-term health effects of daytime compared to night-time eating.
But they described the results are “promising” and suggested that people could improve their health by adjusting the timing of their meals.
Prof Chellappa added that avoiding or limiting eating during night-time hours may benefit night workers, people who suffer from or sleep-wake disorders, people with variable sleep cycles, and those who often travel across time zones.
