Blue Light & Circadian Shifting for Travel
- Adriano dos Santos
- 2 days ago
- 4 min read
Adjusting to a new time zone can feel like a battle against your own body. Fatigue, sluggishness, and sleepless nights can make the first few days of travel exhausting. But with the right approach, you can reset your internal clock and minimize jet lag before you even step off the plane.
Table of Contents:
How I Used Blue Light to Adjust to São Paulo Time
Evening Light Exposure: Delaying My Circadian Rhythm
Morning Light Avoidance: Preventing My Body from Anchoring to Amsterdam Time
Exercise & Meal Timing: Reinforcing My New Sleep Phase
Aligning My Biological Night with My Destination
Why Circadian Disruption is More Than Just Jet Lag
Debunking the Myth: Does Blue Light Always Ruin Sleep
About me
I am Adriano dos Santos, BSc, AFMCP, MBOG, NWP, RSM, ESIM, a Functional Registered Nutritionist, who focuses on nutritional therapy for patients with metabolic syndrome, particularly those suffering from digestive issues and sleep disturbances.
Introduction
Light is one of the strongest signals that regulate our circadian rhythm, influencing when we feel awake or sleepy. Instead of avoiding blue light at night, using it strategically can help shift your body clock and make adjusting to a new time zone easier. Before my trip from Amsterdam to São Paulo, I exposed myself to blue light in the evening and avoided morning light to gradually align my sleep schedule with my destination. Combined with meal timing, exercise, and melatonin, this approach helped me minimize jet lag and adjust faster once I arrived.
How I Used Blue Light to Adjust to São Paulo Time
Evening Light Exposure: Delaying My Circadian Rhythm
One of the most powerful tools for circadian shifting is light exposure, particularly blue light in the evening. São Paulo is four hours behind Amsterdam, which meant I needed to push my bedtime later before I even boarded the plane.
To do this, I increased my exposure to bright blue light at night, keeping my environment well-lit and using devices that emit blue light. This helped suppress melatonin, the hormone that signals sleep, delaying my biological night and aligning it closer to my destination time (Wahl S. et al., 2019).
Morning Light Avoidance: Preventing My Body from Anchoring to Amsterdam Time
In the mornings, I limited my light exposure to avoid reinforcing my body’s connection to Amsterdam’s time zone. Since blue light in the morning helps advance the circadian rhythm, avoiding it allowed me to stay in a delayed phase, making it easier to adjust once I arrived in São Paulo.
I wore sunglasses if I had to go outside early and kept my indoor lighting dim. Studies confirm that avoiding morning blue light can delay the circadian clock, preventing an unwanted phase shift that could make jet lag worse (West K. et al., 2011).
Exercise & Meal Timing: Reinforcing My New Sleep Phase
Food and physical activity are also strong circadian cues. Our bodies rely on meal timing and exercise to regulate our internal clock, so I shifted my habits accordingly.
I ate my meals later in the evening rather than in the morning, reinforcing my body’s adaptation to the new time zone. I also moved my exercise sessions to the evening, since physical activity can delay the circadian clock when performed late in the day (Silvani MI. et al., 2022).
Melatonin Strategy: Aligning My Biological Night with My Destination
To further aid my body clock adjustment, I incorporated low-dose melatonin (0.5 mg) at progressively later times each night. Melatonin works hand-in-hand with light exposure:
Bright blue light in the evening suppressed natural melatonin production, delaying my sleep phase.
A small dose of melatonin at night helped signal to my body that it was time to sleep, even before I arrived in São Paulo.
Melatonin is not just a sleep hormone but also a powerful antioxidant, helping counteract oxidative stress from travel and circadian misalignment (Wahl S. et al., 2019).
Why Circadian Disruption is More Than Just Jet Lag
Crossing time zones doesn’t just make you tired—it causes a misalignment between your internal clock and the external environment. This can lead to:
Increased inflammation
Disrupted mitochondrial function
Weakened immune response
Impaired cognitive and physical performance
Long-haul travelers, shift workers, and even astronauts experience these disruptions. NASA has studied blue light therapy as a non-pharmacological way to enhance alertness, reset circadian rhythms, and improve sleep quality (West K. et al., 2011).
Melatonin also plays a crucial role in recovery. After arriving in São Paulo, I continued taking 0.5–1 mg of melatonin at my new bedtime for the first few nights. This reinforced my new sleep-wake cycle while also reducing the oxidative stress associated with travel (Silvani MI. et al., 2022).
Debunking the Myth: Does Blue Light Always Ruin Sleep?
Many people assume that all blue light exposure at night is bad. While it’s true that blue light suppresses melatonin, the effect depends on the intensity, duration, and timing of exposure.
Prolonged exposure to bright blue light before bed delays sleep onset.
Short or dim exposure (like using a screen on night mode) has a significantly reduced effect.
Blue light from devices alone isn’t strong enough to completely disrupt sleep unless it’s very bright and sustained for hours (West K. et al., 2011).
Instead of fearing blue light, we should use it strategically to shift our circadian rhythms, whether for travel, shift work, or improving daily energy levels.
Conclusion
Jet lag doesn’t have to leave you exhausted for days. By strategically using blue light exposure, avoiding morning light, and shifting meal and exercise timing, you can train your body to adapt faster to a new time zone. Instead of suffering through sleepless nights and groggy mornings, take control of your circadian rhythm and make your transition smoother. Whether you are traveling for business, leisure, or athletic performance, these small adjustments can make a significant difference in how you feel and function.
References:
West K., Jablonski M., Warfield B., Cecil K., James M., Ayers M., Maida J., Bowen C., Sliney D., Rollag M., Hanifin J., Brainard G. (2011). Blue light from light-emitting diodes elicits a dose-dependent suppression of melatonin in humans. Journal of Applied Physiology. https://doi.org/10.1152/japplphysiol.01413.2009
Silvani MI., Werder R., Perret C. (2022). The influence of blue light on sleep, performance and wellbeing in young adults: A systematic review. Frontiers. https://doi.org/10.3389/fphys.2022.943108
Wahl S., Engelhardt M., Schaupp P., Lappe C., Ivanov I. (2019). The inner clock—Blue light sets the human rhythm. Journal of Biophotonics. https://doi.org/10.1002/jbio.201900102
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