How 'Paleo Lighting' Can Improve Your Sleep This Winter

Pixabay / Claudio_Scott

  It's that time of year again. The clocks have been set back, and many of us are turning to SAD lamps, vitamin D supplements, and comforting, carb-heavy one-pot meals to navigate through the extended darkness of winter nights. However, perhaps there's an alternative perspective on the change of season.

What if we choose to embrace the darkness? In appropriate doses and at specific times, darkness plays a vital role in aiding our bodies in rest and recovery, optimizing cognitive function and mental health, and reducing the risk of various illnesses.

The reason for this lies in our circadian rhythms, or body clocks, which respond not only to light but also to its absence. Professor Victoria Revell, a researcher in circadian physiology at the Surrey Sleep Research Centre, emphasizes the importance of keeping the sleep environment as dark as possible with minimal distractions to optimize sleep.

Constantly interrupted sleep has health implications and is associated with conditions like cardiovascular disease, type 2 diabetes, and an increased risk of cancer.

In 2022, Northwestern University researchers discovered that exposure to even moderate light during sleep can negatively impact cardiovascular function. This occurs because light stimulates the sympathetic nervous system, leading to an elevated heart rate and insulin resistance in the morning.

Harvard University conducted a study revealing that blood sugar levels increase with exposure to light at night. Artificial sources of blue light, such as smartphones and similar devices, are believed to have a stimulating effect on our bodies similar to daylight.

While research in this area is not yet conclusive, a notable study in 2017 conducted by researchers from the University of Colorado Boulder provides intriguing insights. In this study, volunteers were taken camping, away from city lights and without access to smartphones or flashlights. Only campfire light was allowed.

The results indicated that the camping experience acted as a 'reset' for the volunteers' body clocks, aligning their sleep and wake patterns with their circadian rhythms. Humans, like many animals, have evolved with a natural sleep-wake cycle synchronized with the day and night cycle.

Similar to how morning light promotes alertness, supports immune function, and benefits mental health, the body also responds positively to darkness. For instance, melatonin, often referred to as the "Dracula hormone," is produced by the pineal gland in response to darkness.

In the Colorado study, campers started producing melatonin two hours earlier, as darkness stimulated its production. Professor Victoria Revell explains, "Melatonin is associated with opening the 'sleep gate,' beginning the process of winding down and getting ready for sleep." Melatonin is also the focus of research for various health conditions.

While the understanding is not yet complete, higher levels of melatonin are linked to a reduced risk of heart disease and certain cancers. However, if we lack exposure to darkness, a permanent shift to dark mode isn't the solution.

Studies indicate that individuals, such as night-shift workers, who experience prolonged periods of darkness, have an increased risk of diseases, including diabetes, heart disease, and obesity. In essence, both light and dark are essential, and their timing is crucial.

Some researchers propose a solution akin to 'paleo lighting,' advocating for a lifestyle that mirrors that of our ancestors. This involves maximizing exposure to daylight during the day and ensuring darkness at night. As the nights grow longer, it's a light bulb moment worth considering.