Simulated Jetlag for Circadian Rhythm

Overseen By Kenneth Wright, PhD

Age: < 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Colorado, Boulder

Disqualifiers: Medical, psychiatric, sleep disorders

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 6

Duration: 7.7 days per condition

14 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to explore how changes in light exposure and meal timing affect the body's internal clocks, which regulate sleep and other bodily functions. Participants will follow a simulated jetlag protocol (also known as the Jet Lag Simulation or Circadian Rhythm Disruption Protocol) by adjusting meal times or being exposed to bright light at specific times. The goal is to better understand how these routines influence certain proteins and hormones in the body, potentially leading to new treatments for issues like jetlag. Healthy individuals who speak English and live at high altitudes, such as Denver, might be a good fit for this trial. As an unphased trial, this study offers a unique opportunity to contribute to groundbreaking research on circadian rhythms.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. However, since the trial excludes participants with any medical, psychiatric, or sleep disorders, it might imply that those on medication for such conditions are not eligible.

What prior data suggests that the simulated jetlag protocol is safe?

A previous study used exposure to bright light to help people adjust their sleep schedules when dealing with jet lag. Participants slept better and experienced no major safety issues. Another study found that changing meal times for simulated jet lag was also safe, though it might temporarily affect gut bacteria. These studies suggest that both light exposure and meal timing are generally well-tolerated in simulated jet lag. However, minor effects, such as changes in sleep patterns or digestion, can occur. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the simulated jetlag protocol for circadian rhythm adjustment because it offers a non-invasive way to reset the body's internal clock. Unlike medications that might be used to treat circadian rhythm disorders, such as melatonin supplements or sleep aids, this protocol uses natural adjustments like meal timing and light exposure. By scheduling meals, bedtimes, and wake times 5 hours earlier, and exposing participants to bright light, the method aims to gently nudge the body's clock into a new rhythm. This approach could offer a more natural and potentially faster way to adapt to time changes, without relying on drugs.

What evidence suggests that this trial's treatments could be effective for circadian rhythm alignment?

This trial will compare the effects of meal timing and bright light exposure on circadian rhythm disruptions. Research has shown that meal timing can reset the body's internal clock, particularly for those experiencing jet lag or working night shifts. Eating earlier in the day can align natural rhythms, potentially boosting health and energy levels. Studies indicate that regular meal times can also regulate stress hormones like cortisol, which irregular schedules can disrupt.

Bright light exposure is another effective method for managing the body's internal clock. Research has found that bright light can adjust sleep patterns and enhance alertness during late-night work. These findings suggest that both meal timing and bright light exposure, tested in this trial, can help manage disruptions to natural rhythms caused by jet lag or irregular work hours. ^{6 7 8 9 10}

Are You a Good Fit for This Trial?

This trial is for individuals interested in participating in a study about body clocks and how they are affected by changes similar to jetlag. The details on who can join are not provided, but typically participants need to be healthy with no major medical conditions that could affect their circadian rhythm.

Inclusion Criteria

Altitude history: Currently residing at Denver altitude or higher

Healthy

I am between 17 and 35 years old.

Exclusion Criteria

I have a health condition that affects my mind, body, or sleep.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

2 visits (in-person)

Pre-Study Preparation

Participants maintain a regular sleep-wake schedule and wear monitoring devices

2 weeks

2 visits (in-person)

Treatment

Participants undergo two experimental conditions: bright light exposure and earlier timed meals, each for 3 days, under a simulated jetlag protocol

7.7 days per condition

2 visits (in-person, 7.7 days each)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Simulated jetlag protocol

Trial Overview The study is testing how simulated jetlag affects proteins in blood and saliva that indicate the timing of our internal body clocks. It aims to understand how light exposure and meal times influence these biological rhythms, potentially leading to new treatments for real-life jetlag.

How Is the Trial Designed?

Group I: Meal timing Experimental Treatment 1 Intervention

Three days of meals, bedtimes and wake times scheduled to occur 5h earlier.

Group II: Bright light Experimental Treatment 1 Intervention

Three days of exposure to bright light of \~3,000 lux, which is less than one-third the brightness of a sunrise or sunset (timed to start earlier by 1h each day) with scheduled bed and wake times timed 5h earlier.

Who Is Running the Clinical Trial?

University of Colorado, Boulder

Lead Sponsor

Trials

128

Recruited

29,600+

University of Colorado, Denver

Collaborator

Trials

1,842

Recruited

3,028,000+

Published Research Related to This Trial

Bright light and melatonin can be effectively used to help people adapt their circadian rhythms when dealing with night shift work or rapid travel across time zones, as shown in various studies.

By implementing a preflight plan to shift circadian rhythms before travel, jet lag can potentially be completely prevented, highlighting the importance of timing these interventions for optimal effectiveness.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

How to trick mother nature into letting you fly around or stay up all night. Revell, VL., Eastman, CI.[2018]

For short trips (1-2 days), it's best to use strategies like naps and caffeine instead of trying to adapt your internal clock, as immediate adaptation is not feasible.

For longer stays (more than 4-5 days), using light exposure and melatonin can help speed up adjustment to new time zones, but individual differences in adaptation can complicate treatment timing.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Managing jet lag: Some of the problems and possible new solutions. Arendt, J.[2013]

Scheduled exposure to bright light can potentially help alleviate jet lag symptoms by speeding up the body's adjustment to new time zones, but laboratory studies have shown mixed results.

Field studies have shown promise, but their small sample sizes raise questions about how well these findings apply to the general population, highlighting the need for more research on optimal light exposure timing and individual differences.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Light treatment for sleep disorders: consensus report. VII. Jet lag. Boulos, Z., Campbell, SS., Lewy, AJ., et al.[2017]

A study involving 28 healthy young subjects found that pre-flight light exposure can effectively phase advance circadian rhythms, with continuous bright light leading to an average advance of 2.1 hours, which can help reduce jet lag after eastward travel.

Both continuous and intermittent bright light treatments significantly outperformed dim light in advancing circadian rhythms, with minimal side effects reported, suggesting that these light strategies could be practical for travelers to mitigate jet lag.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Preflight adjustment to eastward travel: 3 days of advancing sleep with and without morning bright light. Burgess, HJ., Crowley, SJ., Gazda, CJ., et al.[2018]

The study uses mathematical models to analyze how quickly people can adjust their internal body clocks (circadian rhythms) after traveling across time zones, revealing that reentrainment times vary based on the direction of travel and the time of year.

It was found that jet lag can occur not only from east-west travel but also from north-south travel due to changes in daylength, suggesting that travelers should consider these factors to minimize jet lag symptoms.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Reentrainment of the circadian pacemaker during jet lag: East-west asymmetry and the effects of north-south travel. Diekman, CO., Bose, A.[2019]

In a study involving an 85-year-old woman, simulated jet-lag showed that her circadian rhythm was less disrupted in terms of amplitude and sleep efficiency when experiencing a phase delay compared to a phase advance.

The woman's circadian rhythm timing adjusted more quickly during the phase advance condition, suggesting that older adults may respond differently to changes in their sleep-wake cycles depending on the direction of the shift.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Inducing jet lag in an older person: directional asymmetry. Monk, TH., Buysse, DJ., Reynolds, CF., et al.[2019]

Chronobiotic drugs, particularly melatoninergic medications, show promise in helping people adapt to new time zones and mitigate jet lag symptoms, but larger real-life trials are needed to confirm their efficacy.

While no treatment can instantly adjust the body's internal clock to a new time zone, these drugs can help speed up the adaptation process, highlighting the importance of considering both light exposure and pharmacological interventions in managing jet lag.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Approaches to the Pharmacological Management of Jet Lag. Arendt, J.[2019]

The MidnightSun program helps travelers manage jet-lag by calculating optimal light exposure times based on their flight itineraries and geographical locations, potentially aiding in the adjustment of circadian rhythms.

By using a database of over 3000 airports and a user-defined phase response curve for light, the program can recommend specific light exposure strategies to minimize the negative effects of jet-lag.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

MidnightSun: software for determining light exposure and phase-shifting schedules during global travel. Houpt, TA., Boulos, Z., Moore-Ede, MC.[2019]

Bright light exposure has the potential to help resynchronize the circadian system after abrupt time-zone changes, which is important for alleviating jet lag.

However, laboratory studies have not consistently shown that bright light effectively reduces jet lag symptoms, and there are not enough field studies to draw definitive conclusions about its benefits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Bright light: a countermeasure for jet lag? Samel, A., Wegmann, HM.[2019]

Citations

1. nature.com nature.com/articles/s41598-024-83789-3

A systematic review and meta-analysis on light therapy for ... Meta-analysis results showed a significant delay in rhythm phase (1.72 h delay) within the LT group, this is consistent with the previous ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6746555/

Bright Light Therapy: Seasonal Affective Disorder and Beyond In contrast, only 32% of the 31 patients receiving placebo achieved remission during the study, and the difference was statistically significant (difference in ...

3. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8259707/

Efficacy of intermittent exposure to bright light for treating ... Besides enhancing circadian adaptation, the bright light treatment was effective in preventing the slowing of response times on both the night shift as well as ...

4. sciencedirect.com sciencedirect.com/science/article/pii/S1087079218301886

Light therapies to improve sleep in intrinsic circadian ... Meta-analysis showed improvements in sleep continuity (ES = −0.23, p = 0.000), self-reported sleep disturbance (ES = −0.32, p = 0.014), and advancement of ...

5. clinicaltrials.gov clinicaltrials.gov/study/NCT05382923

NCT05382923 | Facilitating Adjustment to Simulated Jet Lag The aims of this study are to compare 3 different treatments for circadian adjustment to a laboratory protocol which will mimic westward air ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC3086113/

Jet Lag: Current and Potential Therapies - PMC Jet lag is a sleep disorder from rapid travel causing a mismatch with the body's rhythm, leading to disturbed sleep, fatigue, and reduced alertness.

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC1249488/

Advancing Circadian Rhythms Before Eastward Flight To reduce jet lag, advance sleep by 1 or 2 hours daily with morning bright light. 2 hours advance is not better than 1 hour.

8. withpower.com withpower.com/trial/phase-circadian-rhythms-8-2023-d2f64?condition=&query=Meal+Timing+and+Sleep&overallStatus=Recruiting&hasNoPlacebo=false

Simulated Jetlag for Circadian Rhythm The safety of the Simulated Jetlag Protocol, which involves exposure to bright light to adjust circadian rhythms, has been studied in the context of jet lag.

9. nature.com nature.com/articles/s41398-020-0694-0

Circadian rhythm disruption and mental health Circadian rhythms are internal manifestations of the solar day that permit adaptations to predictable environmental temporal changes.

10. aasm.org aasm.org/wp-content/uploads/2017/07/Review_CircadianRhythm.pdf

Part I, Basic Principles, Shift Work and Jet Lag Disorders This review covers circadian rhythm sleep disorders, including basic principles, shift work, jet lag, and treatments like timed light and melatonin.