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Cited by 45Sleep and related disordersCircadian rhythm and melatoninSleep and Wakefulness Research

Association between lunar phase and sleep characteristics

Turányi, Csilla Zita, Rónai, Katalin Zsuzsanna, Zoller, Rezső, Véber, Orsolya, Czira, Mária Eszter, Újszászi, Ákos, László, Gergely, Szentkirályi, András +9 more·2014·Sleep Medicine
DOI 10.1016/j.sleep.2014.06.020
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Abstract

Objectives Popular belief holds that the lunar cycle affects human physiology, behavior, and health, including sleep. To date, only a few and conflicting analyses have been published about the association between lunar phases and sleep. Our aim was to analyze the relationship between lunar phases and sleep characteristics.Methods In this retrospective, cross-sectional analysis, data from 319 patients who had been referred for sleep study were included. Individuals with apnea-hypopnea index ≥ 15/h were excluded. Socio-demographic parameters were recorded. All participants underwent one-night standard polysomnography. Associations between lunar cycle (new moon, full moon and alternate moon) and sleep parameters were examined in unadjusted and adjusted models.Results Fifty-seven percent of patients were males. Mean age for men was 45 ± 14 years and 51 ± 12 years for women. In total, 224 persons had their sleep study done during alternate moon, 47 during full moon, and 48 during new moon. Full moon was associated with lower sleep efficiency [median (%) (IQR): new moon 82 (18), full moon 74 (19), alternate moon 82 (15); P < 0.001], less deep sleep [median (%) (IQR): new moon 9 (9), full moon 6 (4), alternate moon 11 (9); P < 0.001], and increased REM latency [median (min) (IQR): new moon 98 (74), full moon 137 (152), alternate moon 97 (76); P < 0.001], even after adjustment for several covariables.Conclusion The results are consistent with a recent report and the widely held belief that sleep characteristics may be associated with the full moon.

AI snapshot

Written from the paper’s full text.

TL;DR

In a retrospective cross-sectional polysomnography cohort of 319 patients without moderate-to-severe obstructive sleep apnea, full moon was associated with lower sleep efficiency, less deep sleep, and longer REM latency, even after adjustment. These associations were generally more pronounced in women.

Key findings

  • Full moon was associated with lower sleep efficiency (median[IQR] new moon 82[18], full moon 74[19], alternate moon 82[15], p<0.001), less deep sleep (new moon 9[9], full moon 6[4], alternate moon 11[9], p<0.001), and longer REM latency (new moon 98[74] min, full moon 137[152] min, alternate moon 97[76] min, p<0.001); associations remained significant after adjustment for covariates including comorbidity and depressive symptoms.
  • Post hoc analyses showed higher wake percentage (28.7±12.3 vs. 20.2±12, p<0.05) and lower REM percentage (10.1±6.6 vs. 13.9±6.6, p<0.05) at full moon compared with alternate moon; sleep latency was also longer at full moon (p=0.001).
  • Gender interaction was significant for deep sleep (p=0.01) and sleep latency (p=0.01), with differences generally more pronounced in women. Subjective sleep onset latency was longer at full moon in women (median[IQR] new moon 30.0[25] min, full moon 52.5[66] min, alternate moon 25.0[50] min, p=0.04) and nearly significant in men (p=0.06).
  • Overall, subjective sleep-related parameters were not significantly different between the three moon-phase groups (Table 4).

Methods

  • Retrospective, cross-sectional analysis of 319 consecutive patients referred for sleep study at Semmelweis University, Budapest, between January 2007 and November 2009; exclusions included technical limitations, AHI ≥15/h, and sleep efficiency under 20%. Participants underwent one-night standard attended polysomnography and completed questionnaires including the Athens Insomnia Scale, CES-D, Stanford Sleepiness Scale, and subjective sleep log.
  • Lunar phase was categorized as new moon, full moon, or alternate moon; sensitivity analyses used cutoffs of ±1, ±2, and ±3 days around new/full moon. Associations were examined unadjusted and adjusted for age, gender, smoking, coffee consumption, sleeping pills, regular exercise, Charlson Comorbidity Index, and CES-D score, using ANCOVA or Kruskal-Wallis tests with post hoc Sidak or Mann-Whitney tests with Bonferroni correction; gender interaction was tested.

Limitations

  • Stated by the authors: the retrospective, cross-sectional design prevented detecting temporal change in sleep characteristics as a function of the moon cycle in a within-subject design; the sample was referred to a sleep clinic and not representative of the healthy general population; clinical suspicion for sleep problems might have made participants more sensitive to the lunar cycle; and there was no normal control group or hormonal profile measurement.
  • Evident from the text: moon-phase groups were highly unequal (full moon n=47, new moon n=48, alternate moon n=224), which may limit statistical balance and power.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1016/j.sleep.2014.06.020

Cites

63 of 63 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 6 cited sources checked · 0 supported · 0 flagged

  • Findingown data
    § WORD COUNT · p. 3

    Full moon was associated with less deep sleep compared to other lunar phases.

    “less deep sleep (median(%)[IQR] new moon 9[9], full moon 6[4], alternate moon 11[9], p<0.001)”
    • Also stated in: § RESULTS · p. 9 · plain
      “Post hoc analyses revealed less deep sleep percentage (6.1[4] vs. 10.9[9], p<0.05) and REM percentage (10.1±6.6 vs. 13.9±6.6, p<0.05), higher wake percentage (28.7±12.3 vs. 20.2±12, p<0.05) at full moon compared to alternate moon phases.”
    • Also stated in: § DISCUSSION · p. 11 · plain
      “In our analysis we also found less deep sleep at the time of full moon, compared to other lunar phases.”
    Quote in the paperSubstantial claim
  • Findingown data
    § RESULTS · p. 10

    Subjective sleep-related parameters were not significantly different between the three lunar phase groups.

    “Subjective sleep-related parameters were not significantly different between the three groups (Table 4).”
    Quote in the paperNot a substantial claim
  • Findingown data
    § RESULTS · p. 10

    The interaction between gender and lunar phases was significant for sleep latency.

    “The interaction between gender and lunar phases was significant for deep sleep (p=0.01) and sleep latency (p=0.01)”
    Quote in the paperSubstantial claim
  • Findingown data
    § RESULTS · p. 9

    Deep sleep percentage was significantly different between the three lunar phase groups.

    “Deep sleep (p<0.001), wake (p<0.001) and REM (p=0.002) percentages were significantly different between the three groups.”
    Quote in the paperSubstantial claim
  • Findingown data
    § RESULTS · p. 9

    Full moon was associated with lower REM percentage compared to alternate moon phases.

    “REM percentage (10.1±6.6 vs. 13.9±6.6, p<0.05)”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim. 12
  • May combine two claims. 9

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data
    § Acknowledgments · p. 20

    REM sleep percentage was lower in full moon than alternate moon.

    “REM sleep (%) | 13.1 ± 5.8 | 10.1 ± 6.6 | 13.9 ± 6.6 | 0.002 | 0.046 | 0.100 | 0.117 | F<A |”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Acknowledgments · p. 20

    REM latency was higher in full moon than new moon and alternate moon.

    “REM latency (min) | 98[74] | 137[152] | 97.5[76] | 0.001 | 0.015 | 0.034 | 0.040 | F>N, F>A |”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data
    § Acknowledgments · p. 20

    Sleep latency was higher in full moon than new moon and alternate moon.

    “Sleep latency (min) # | 12.1[14] | 24.5[31] | 13.3[19] | 0.001 ῀ | 0.009 | 0.010 | 0.077 | F>N, F>A |”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductnone given
    § DISCUSSION · p. 13

    Neither the patients nor the personnel in the sleep laboratory were aware of the planned analysis of the lunar cycle.

    “Neither the patients, nor the personnel in the sleep laboratory were aware of our planned analysis, thus avoiding the confounding of self-fulfilling prophecy regarding a lunar influence on sleep.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductnone given
    § DISCUSSION · p. 13

    The study excluded the effect of light, and everyone slept under standard circumstances with the same bedtime and wake-up time.

    “We excluded the effect of light, furthermore everyone slept under standard circumstances, bedtime and wake up was at same time for the patients.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation
    § Polysomnography · p. 6

    All polysomnography recordings were scored visually per 30 s epochs by experienced scorers according to the criteria of Rechtschaffen & Kales.

    “All recordings were scored visually per 30 s epochs by experienced scorers according to the criteria of Rechtschaffen & Kales [39].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [39] Rechtschaffen A, K.A., A manual of standardized terminology, techniques, and scoring system for sleep stages of human subjects. . National Institutes of Health, 1968. Washington DC: Publication 204.

      Not checked in the free run.

  • May combine two claims.

    Study design and conductown data
    § RESULTS · p. 9

    There were no significant differences regarding age, gender, BMI, use of sleeping pills, coffee consumption, shift work, Charlson Comorbidity Index, CESD score and sleep disorders between the lunar phase sub-groups.

    “There were no significant differences regarding age, gender, BMI, use of sleeping pills, coffee consumption, shift work, Charlson Comorbidity Index, CESD score and sleep disorders in the study sub-groups (Table 1).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning
    § RESULTS · p. 8

    319 patients were included in the final analysis.

    “Thus, 319 patients were included in the final analysis.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data
    § Statistical analysis · p. 8

    The study used sensitivity analyses with three different cut-off points (one, two, and three days before and after new/full moon) to define full moon.

    “For sensitivity analysis we repeated our analysis using three different cut off points: 1) New/Full moon and one day before and one day after; 2: New/Full moon and two days before and after; 3: New/Full moon and three days before and after.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductown data
    § Statistical analysis · p. 8

    The analyses were adjusted for age, gender, smoking, coffee consumption, use of sleeping pills, regular exercise, Charlson Comorbidity Index, and CES-D score.

    “We adjusted our analyses for several co-variables, reportedly associated with sleep characteristics: age [42], gender [33], smoking [43], coffee consumption [44], use of sleeping pills [45], regular exercise [46], Charlson Comorbidity Index and CES-D score [47].”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given
    § Questionnaires · p. 6

    Participants completed a battery of validated questionnaires, including the Athens Insomnia Scale.

    “Participants completed a battery of validated questionnaires, including the Athens Insomnia Scale (AIS)”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given
    § WORD COUNT · p. 3

    Only a few and conflicting analyses have been published about the association between lunar phases and sleep.

    “To date, only a few and conflicting analyses have been published about the association between lunar phases and sleep.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Interpretationreasoning
    § DISCUSSION · p. 11

    A novelty of our study is the enrollment of patients referred to a sleep clinic, thereby extending previous observations regarding the association between lunar cycle and sleep variables to a clinical population with potential sleep disorders.

    “A novelty of our study is the enrollment of patients referred to a sleep clinic, thereby extending previous observations regarding the association between lunar cycle and sleep variables to a clinical population with potential sleep disorders.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Study design and conductnone given
    § DISCUSSION · p. 14

    The study lacked a normal control group and hormonal profile measurements.

    “Another limitation of this study is the absence of the normal control group and hormonal profile measurements.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data
    § WORD COUNT · p. 3

    Our results are consistent with a recent report and the widely held belief that sleep characteristics may be associated with the full moon.

    “Our results are consistent with a recent report and the widely held belief that sleep characteristics may be associated with the full moon.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given
    § DISCUSSION · p. 14

    Participants had clinical suspicion for sleep problems, which might have made them more sensitive to the lunar cycle.

    “Furthermore, the fact that these participants had clinical suspicion for sleep problems, might have made them more sensitive to the lunar cycle.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data
    § DISCUSSION · p. 13

    The association of full moon with sleep efficiency and other sleep parameters remained significant after correcting for depression and comorbidity, so these factors are unlikely to explain the findings.

    “The association of full moon with sleep efficiency and other sleep parameters remained significant after correcting for depression and comorbidity, and thus it is unlikely that these factors could explain our findings.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation
    § DISCUSSION · p. 13

    The moon is a relatively minor source of light in our times.

    “However, as Rotton et al. pointed out, the moon is a relatively minor source of light in our times, therefore human behavior would be much more erratic if it were affected by light levels of this magnitude [61].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [61] Rotton, J. and I.W. Kelly, Much ado about the full moon: a meta-analysis of lunar-lunacy research. Psychol Bull, 1985. 97(2): p. 286-306. source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation
    § INTRODUCTION · p. 5

    There is a strong link between gender and sleep both in the structure of sleep and in the incidence of various sleep disorders.

    “There is a strong link between gender and sleep both in the structure of sleep as in the incidence of various sleep disorders [32, 33].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [32] Shechter, A. and D.B. Boivin, Sleep, Hormones, and Circadian Rhythms throughout the Menstrual Cycle in Healthy Women and Women with Premenstrual Dysphoric Disorder. International Journal of Endocrinology, 2010. source

      Not checked in the free run.

    • cites [33] Krishnan, V. and N.A. Collop, Gender differences in sleep disorders. Curr Opin Pulm Med, 2006. 12(6): p. 383-9. source

      Not checked in the free run.

19 of 19

  • The paper relies on this without support.

    People living in large cities are less likely to be aware of the lunar cycle.

    “people living in large cities are less likely to be aware of lunar cycle”

  • The paper relies on this without support.

    The majority of the participants lived in the capital of Hungary.

    “the majority of the participants in fact lived in the capital of Hungary”

  • The paper relies on this without support.

    Poor sleep causes emotional lability and reduced daytime functioning.

    “Accordingly, poor sleep and the consequent emotional lability and reduced daytime functioning can be partially related to the full moon.”
3 of 3

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Recent reports of lunar month variation of total sleep time in healthy individuals seem consistent with the finding of lunar month variation in onsets of mania.

    “In this regard, recent reports of lunar month variation of total sleep time in healthy individuals seem consistent with the finding of lunar month variation in onsets of mania”

    From Bipolar mood cycles and lunar tidal cycles (2018) · cites this paper as [38]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • PLMS percentage does not match the cohort size

    Minor

    Among 319 included patients, 114 represent 35.74%, which rounds to 36%, not the reported 35%.

    Reported 35 · recomputed 35.736677

  • Reported male percentage conflicts with the gender count

    Minor

    The table reports 144 women among 319 participants, leaving 175 men, or 54.9%, rather than 57%.

  • Charlson Comorbidity Index interquartile range differs

    Minor

    The results report an interquartile range of 2.0 for the total population, whereas Table 1 reports 1.

  • Women's mean age differs between abstract and results

    Minor

    The abstract gives women's mean age as 51 years, while the results give 52 years.

  • Sleeping-pill use percentage uses an inconsistent denominator

    Minor

    Table 1 reports 23 users among 319 participants as 8.3%; that count is 7.21% of the stated total.

    Reported 8.3 · recomputed 7.210031

5 of 5

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Authors
Turányi, C. Z., Rónai, K. Z., Zoller, R., Véber, O., Czira, M. E., Újszászi, Á., László, G., Szentkirályi, A., Dunai, A., Lindner, A., Szőcs, J. L., Becze, Á., Kelemen, A., Lendvai, Z., Molnar, M. Z., Mucsi, I., & Novák, M.
Affiliations
  • Semmelweis University (HU)
  • University of Tennessee Health Science Center (US)
Corresponding author
Mucsi, István
ORCID
Venue
Sleep Medicine
Publisher
Elsevier BV
Published
2014-11
Volume
15
Issue
11
Pages
1411-1416
ISSN
1389-9457 (ISSN-L)
DOI
10.1016/j.sleep.2014.06.020
OpenAlex
W1992027680
Semantic Scholar
05f0454985771db78ae6df1951407362209869e1
Cited by
45
References
63
Citations by year
2026: 4 · 2025: 8 · 2024: 1 · 2023: 5 · 2022: 3 · 2021: 3 · 2020: 5 · 2019: 1 · 2018: 4 · 2017: 2 · 2016: 4 · 2015: 4 · 2014: 1
FWCI
5.09
Type
journal article
Language
en
Open access
closed
Licence
www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations
  • Sleep Medicine (publishedVersion)
  • PubMed (publishedVersion)
  • Semmelweis University Repository (Semmelweis University) (submittedVersion)
Topics
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Sleep and Wakefulness Research
Keywords
lunar phases, full moon, sleep efficiency, slow-wave sleep, REM latency, sleep architecture, sleep characteristics
MeSH terms
Cross-Sectional Studies, Female, Humans, Sleep Initiation and Maintenance Disorders, Male, Middle Aged, Retrospective Studies, Sleep, Sleep, REM, Moon, Polysomnography

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