New Delhi— While shift work is already known to increase the risk of cardiovascular issues, a new study released on Tuesday suggests that eating exclusively during the daytime may help mitigate those risks.
Although sleep timing has long been a focus of research, scientists from Mass General Brigham in the U.S. and the University of Southampton in the U.K. found that meal timing could play an even more significant role in cardiovascular health.
Earlier studies have linked night shift work to serious health problems, particularly heart-related conditions, due to circadian misalignment — when the body’s behavioral cycles are out of sync with its internal biological clock.
In the new study, researchers observed that several cardiovascular risk factors — including markers of the autonomic nervous system, elevated levels of plasminogen activator inhibitor-1 (a protein linked to increased blood clot risk), and higher blood pressure — rose after night work. However, these risk factors remained stable in participants who consumed food only during daytime hours.
“Avoiding or limiting food intake during the night may benefit not only night shift workers, but also those with insomnia, irregular sleep-wake cycles, or frequent jet lag,” the researchers wrote in the study, which was published in the journal Nature Communications.
The study involved 20 healthy young adults who, for two weeks, were placed in an environment without windows, clocks, or electronic devices — eliminating any external cues that might influence their internal body clocks.
Participants underwent a “constant routine protocol,” a carefully controlled lab setting designed to isolate the effects of circadian rhythms from environmental and behavioral factors such as light exposure and sleep patterns.
As part of this protocol, participants stayed awake for 32 hours in dim lighting, maintained a fixed body posture, and were given identical snacks every hour.
They then underwent a simulation of night shift work and were randomly assigned to one of two groups: one that ate during the nighttime (mimicking typical night shift behavior), and another that ate only during daytime hours.
Both groups followed identical nap schedules, so any differences in cardiovascular risk were attributed solely to the timing of food intake — not sleep duration or quality.
“Our study controlled for every variable we could imagine that might influence the results,” said lead author Dr. Sarah Chellappa, Associate Professor at the University of Southampton. “This allows us to confidently say that the timing of meals is what’s driving the changes in cardiovascular risk factors.”
While more research is needed to understand the long-term impact of daytime versus nighttime eating, the researchers described the findings as “promising” and emphasized that adjusting meal timing could be a simple, effective way for people — especially night workers — to support heart health. (Source: IANS)
