Light runs the world, literally. On the most basic level, we spin around the sun, which gives us our days and nights. It's a fundamental factor shaping our health and vitality as human beings. Its effects on our biological rhythms, mood, and overall wellness are profound and multifaceted.
Yet, as we’ve evolved, so have our light sources. No longer limited to the sun, we’ve got computers, phones, overheard fluorescent LEDs, headlights screaming at us on our drive home from work, and televisions we fall asleep to. All of these sources of light affect our brains, which are still really only built to understand sunlight. By unraveling the intricacies of light's influence on our bodies, we gain valuable insights into how to harness its power for better health.
What Light Does For Us Throughout the Day
At the core of light's impact on wellness lies its role in regulating our circadian rhythm—the internal clock governing our sleep-wake cycle and various physiological processes. This rhythm is finely tuned to the 24-hour solar day, ensuring that our bodies align with the natural ebb and flow of light and darkness. Through this synchronization, from the moment we open our eyes, light gets to work running our brains, explains Andrew Huberman, neuroscientist and associate professor of neurobiology and ophthalmology at Stanford University School of Medicine.
“Light directly impacts our mood, sleep, ability to wake up and focus, hormone levels, immune system, and ability to cope with stress,” Huberman says.
Morning light exposure sets the tone for the day. Researchers have found that exposure to bright morning light promotes the release of cortisol, the hormone responsible for wakefulness and alertness. Moreover, morning sunlight stimulates serotonin production, enhancing mood and combating symptoms of seasonal affective disorder (SAD), which affects around 5 percent of Americans every winter.
As you move through your day, bright overhead lights during the rest of the morning and early afternoon bolster cognitive function and productivity by stimulating the release of neurotransmitters like dopamine and norepinephrine. This heightened alertness is essential for tackling tasks requiring focus and attention.
Afternoon sunlight serves as the “second anchor point” of the day, signaling the onset of evening and promoting relaxation. This shift in the light spectrum—characterized by warmer tones of yellow and orange—conveys important timing information to our circadian clock, helping to maintain its stability.
As the day wanes, dimming lights and minimizing exposure to blue light become imperative to facilitate the transition to sleep. Blue light, emitted abundantly by electronic devices (you know the ones), can disrupt melatonin production, impairing our ability to unwind and achieve restful sleep.
The Problem With Our Light Sources
So we know what light can do for us, but the reality is most of us aren’t getting most of these benefits. Instead, we’re breaking up our natural cycles at every turn. We’re looking at our phones the second we awake, or not getting outside in the afternoon to establish our second anchor point. Our poor sleep/wake cycles create adverse health effects, increasing our risks for or contributing to sleep disorders, depression, obesity, diabetes, heart disease, and cancer.
The main problem with most of our lighting particularly in offices and shared public spaces where most of us are spending the bulk of our day, is that it doesn’t account for our circadian rhythms. It’s not working with what’s happening outside, those natural ebbs and flows described above.
“Artificial lighting in the office is not normal, to have the same amount of light all day every day is not normal,” said Ray Molony, the managing editor of Lux Review, in a conversation on office lighting with Curbed. “There’s now a trend, which is to think about, Let’s have lighting that increases in intensity and is more in tune with what we expect as humans.”
Yet, it’s mostly still a trending thought rather than everyone swapping out light bulbs. So how do we set our brains up for success?
Tips for Getting the Right Light in Your Day
Step 1: Get that bright morning light. On a sunny day, 5-10 minutes of direct exposure, and at least 20 on overcast days. Implementing a light-centric morning routine can set a positive trajectory for the day ahead. Whether through outdoor activities or the use of light boxes, prioritizing direct morning light exposure jumpstarts our circadian rhythm, boosts mood, and enhances cognitive function. Dawn simulators for those trying to get through the dark winter months offer a gentle alternative for those unable to access natural sunlight, gradually awakening the body in sync with the rising sun.
Step 2: Adapt lighting environments to mimic natural light patterns. Bright overhead lights promote alertness and productivity during peak hours, while softer illumination aids relaxation as bedtime approaches. Huberman says to increase the ambient light of your workspace rather than the brightness of the computer screen. Ideally, also place your desk near a window, as natural sunlight signals the brain to stay alert and focused.
Step 3: Shut it down when the sun goes down. Yes, you really do need to put that phone down when the sun goes down. Blue light wavelengths stimulate your brain and doing so when trying to wind down messes with the chemicals trying to tell your body to prepare for sleep. Additionally, sleep in as dark a room as possible. Research shows even dim light can affect your sleep cycle. If you need to get up, for the kiddo with a nightmare, or to go to the bathroom, red lights help preserve melatonin levels and keep your brain in a true rest state.
Conclusion
The profound impact of light on our health underscores the importance of integrating mindful lighting practices into our daily lives. By aligning our routines with the natural rhythms of light, we can optimize our well-being and vitality. As we navigate the modern world dominated by artificial lighting, prioritizing exposure to natural light and embracing lighting strategies rooted in circadian science can pave the way for a healthier, more balanced life.
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