Daytime-Only Eating May Protect Heart Health in Night Shift Workers: Study

New Delhi: A new study has revealed that restricting food intake to daytime hours could help prevent heart-related risks commonly associated with night shift work. The research, conducted by scientists from Mass General Brigham in the US and the University of Southampton in the UK, highlights that meal timing might play a more critical role than previously believed in influencing cardiovascular health.

While shift work has long been recognized as a risk factor for cardiovascular disease due to circadian misalignment—when behavioral patterns like sleeping and eating do not align with the body’s internal clock—this study shines a light on food timing as a potentially more significant contributor to heart risks than sleep disruptions.

The findings, published in Nature Communications, showed that key cardiovascular risk markers—such as blood pressure, plasminogen activator inhibitor-1 (a protein linked to increased blood clotting risk), and autonomic nervous system activity—worsened after simulated night shift work. However, these markers remained stable in participants who ate only during the daytime.

To investigate the impact of food timing, the researchers recruited 20 healthy young adults and subjected them to a tightly controlled laboratory setting. Participants were kept in an environment without exposure to natural light, clocks, or electronic devices to eliminate external cues about time. They followed a “constant routine protocol,” remaining awake for 32 hours in dim light, eating identical snacks at hourly intervals, and maintaining a fixed posture.

After this phase, participants underwent a simulated night shift schedule and were split into two groups: one ate only during the day, while the other consumed meals at night—mirroring typical shift worker behavior. Importantly, both groups followed the same nap schedule, allowing researchers to isolate the effects of food timing.

“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 driving these changes in the cardiovascular risk factors,” said lead author Sarah Chellappa, Associate Professor at the University of Southampton.

The researchers noted that although more studies are needed to evaluate long-term outcomes, the findings suggest that daytime-restricted eating could be a simple yet effective strategy to reduce heart disease risk in shift workers, frequent travelers, and people with irregular sleep schedules or insomnia.