Study insight: Light exposure during sleep impairs cardiometabolic function
In a landmark study authored by Ivy C. Mason, Daniela Grimaldi, Kathryn J. Reid and Phyllis C. Zee, examined the effect of nighttime light exposure on cardiometabolic health. The research, published March 14, 2022 under the title "Light exposure during sleep impairs cardiometabolic function" in the PNAS Journal, sheds light on the potential risks associated with nighttime light during sleep.
A night of light exposure leads to increased heart rate and insulin resistance
The study involved 20 young adults and followed a parallel group study design. One group slept one night in low light (<3 lx) and one night in overhead room lighting (100 lx), while the other group slept two consecutive nights in low light. The results showed that a single night of room light during sleep increased nocturnal heart rate, decreased heart rate variability and increased insulin resistance the next morning compared to sleeping in a dimly lit environment.
Reasons and explanation
The authors also investigated potential mechanisms that could explain this effect. It was found that higher sympathovagal balance during sleep in the room light condition was associated with increased insulin resistance the next morning. This suggests that activation of the sympathetic nervous system may play a role in the observed changes in insulin sensitivity.
Significance
The significance of these findings extends beyond mere scientific curiosity. The results suggest that avoiding light exposure during nighttime sleep could have positive effects on cardiometabolic health. In a world often characterized by night-time lighting, this could have important implications for public health.
This research not only provides a deeper insight into the links between light exposure and health, but also a basis for future research and preventative measures. It underlines the importance of a conscious approach to night-time lighting and provides food for thought about the potential impact on our well-being.
Conclusion
Make sure your room is dark when you want to sleep. This will help you to have a restful and healthy sleep and wake up more rested in the morning.
Source: "Light exposure during sleep impairs cardiometabolic function" https://www.pnas.org/doi/full/10.1073/pnas.2113290119
