By Jamie Rokin
It is hard to imagine that artificial light is a relatively new addition to humanity. For most of human history, daylight meant activity, and darkness meant rest. It wasn’t until the invention of the first streetlights in the early 19th that after sunset was economically and socially usable.
While modern life has granted us the convenience of functioning in the otherwise, natural darkness, our biological systems remain attuned to day and night as we had known them for millennia.
The circadian rhythm is your body’s internal 24-hour clock. It’s primarily regulated by light, especially sunlight, which signals your brain when it’s daytime and when night is approaching.
In response, your body releases hormones like cortisol to help you wake up and melatonin to help you sleep, while also coordinating digestion, metabolism, body temperature, and cellular repair. When your circadian rhythm is aligned with natural light and dark cycles, your body functions smoothly and efficiently; when it’s disrupted by irregular schedules or artificial light, everything from sleep quality to mood and energy can feel off.
So, how do we honour our natural rhythm in the modern era? How do we keep our smartphones, laptops, and lightbulbs without interrupting our internal systems?
It’s time to get reacquainted with the sun.
Exposure to natural light early in the day acts as an anchor for the body’s internal clock, clearly signaling that it is daytime and setting the timing for the next 24-hours of biological activity. The sun will trigger a healthy rise in cortisol to promote alertness, while also establishing the timing for melatonin release later in the evening to support restful sleep.
Modern life exposes us to light at all hours, especially blue-heavy light from screens. Going outside during the day strengthens the contrast between day and night in your nervous system. When your body clearly recognizes daytime, it becomes more resilient to small amounts of artificial light in the evening.
Here are a few simple ways to build sunlight into your daily routine.
- Let the sun be your first morning light. Go outdoors for at least five minutes within your first hour of waking; before your morning coffee, and before checking your phone.
- Spend your work breaks outside. Even short bursts of outdoor light throughout the day can have a dramatic impact on your mood, and help your body reinforce the day-night contrast.
- Choose outdoor movement. When the weather permits, even a walk or outdoor mobility session will deliver very positive circadian input.
- Watch the sunset: Not only is it a perfect opportunity for a mindful moment, but natural light softens and shifts in tone, signaling to your body that it’s time to wind down.
At Shoo Foo, we believe in progress over perfection. You don’t have to spend hours outside; even small doses of sunlight throughout the day will help you feel more aligned with your natural rhythm.
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References
Cho, Yumi, et al. “Effects of Artificial Light at Night on Human Health: A Review.”Chronobiology International, vol. 36, no. 3, 2019, pp. 365–379. PubMed Central, https://pmc.ncbi.nlm.nih.gov/articles/PMC6751071/.
Roenneberg, Till, and Martha Merrow. “The Circadian Clock and Human Health.” Current Biology, vol. 26, no. 10, 2016, pp. R432–R443, PubMed Central, https://pmc.ncbi.nlm.nih.gov/articles/PMC8645190/.
Blume, C., et al. “Effects of Light on Human Circadian Rhythms, Sleep and Mood.” Journal of Physiological Anthropology, vol. 38, 2019. PubMed Central, https://pmc.ncbi.nlm.nih.gov/articles/PMC6751071/.
Crowley, S. J., et al. “Phase Advancing Human Circadian Rhythms with Morning Bright Light Exposure.” Journal of Circadian Rhythms, vol. 12, 2014, https://pmc.ncbi.nlm.nih.gov/articles/PMC4344919/
