Moonstruck! Does The Full Moon Influence Behavior?

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It happens at least once every month. Sometimes, rarely, it happens twice a month. Up there in the sky. It's a bird. It's a plane. No, it's a FULL MOON. Popular legend has it that the full moon brings out the worst in people: more violence, more suicides, more accidents, more aggression. The influence of the moon and behavior has been called "The Lunar Effect" or "The Transylvania Effect." The belief that the full moon causes mental disorders and strange behavior was widespread throughout Europe in the middle ages. Even the word "lunacy" meaning "insanity" comes from the Latin word for "moon." You may hear people say, "Just ask an emergency room nurse or a police phone operator. They will tell you that they are busier on nights when there is a full moon." Is there scientific evidence to support these beliefs? Let's look at the data.

Violence, Aggression and Crime 11,613 cases of aggravated assault in a 5-year period: assaults occurred more often around the full moon. Reference: Human aggression and the lunar synodic cycle (1978) 284 crimes in a 1-year period: no significant difference in the number of crimes on full moon days and non full moon days. Reference: Full Moon days and crime: Is there any association? (2010) 34,318 crimes in a 1-year period: crimes occurred more frequently during the full moon. Reference: J. Psychology, vol. 93:81-83, 1976. 58,527 police arrests in a 7-year period: no difference in the number of arrests made during any phase of the moon. Reference: Antisocial behavior and lunar activity: a failure to validate the lunacy myth (1977) 361,580 calls for police assistance in a 3-year period: calls had no relationship to the phase of the moon when the day of the week, holiday and year were controlled. Reference: Perceptual and Motor Skills, 57:993-994, 1983. 908,000 service calls to police in a 8-year period: calls to police did not increase during the full moon. Reference International Journal of Criminal Justice Sciences, 12:129-138, 2017. 1,289 aggressive "incidents" by hospitalized psychiatric patients in a 105-week period: no significant relationship between the severity or amount of violence/aggression and phase of the moon. Reference: Lunar cycles and violent behaviour (1998) 91 patients who presented to the emergency department with violent and acute behavioral disturbance in a 1-year period: biolent and acute behavioural disturbance occurred more often during the full moon. Reference: The dark side of the moon (2009) The rate of agitation in 24 nursing home residents in a 3-month period: no significant relationship of agitation to moon phase. Reference: Full moon: Does it influence agitated nursing home residents? (1989) The number of aggressive offenses (fighting, threatening or assaulting an officer, creating a disturbance) for 1,300 male inmates in a medium security prison in a 1-year period: no significant relationship between agressive offenses and moon phase. Reference: Full moon: Aggression in a prison setting as a function of lunar phases (1998) The number of police calls for service in a five year period (2001-2005): no significant relationship between the volume of crime and lunar phase. Reference: Bad moon on the rise? Lunar cycles and incidents of crime (2010) 1,329 assaults in four prisons in a 2-year period: no difference in the number of assaults on full moon and non-full moon days. Reference: Atlas, R., Violence in prison. Environmental influences, Enviro. Beh., 16:275-306, 1984. 2,017 homicides in a 3-year period: no relationship between the number of homicides and the phase of the moon. Reference: Porkorny, A.D., Moon phases, suicide, and homicide, Am. J. Psychiatry, 121:66-67, 1964. 20,500 homicides in the United States in a 1-year period: no relationship between the number of homicides and the phase of the moon. Reference: Temporal variation in suicide and homicide (1979) 6,808 homicides committed in Finland in a 54-year period: there were 15% less homicides committed during the full than committed during the new moon. Reference: Nayha, S., Lunar cycle in homicides: a population-based time series study in Finland, BMJ Open, 2019;9:e022759. doi: 10.1136/bmjopen-2018-022759 (2019) 1,840 incidences of "acting-out" in people in a psychiatric treatment facility in a 3-year period: no relationship between the number of acting-out incidences and the phase of the moon. Reference: Lunar phase and acting-out behavior (1986) 23,142 incidences of battery (aggravated assault) in a 7-year period in Germany: no relationship between the number of aggravated assaults and the phase of the moon. Reference: Relationship between lunar phases and serious crimes of battery: a population-based study (2010) 12,200 incidences of aggression in people with intellictual disabilities in a 17-year period: no relationship between aggressive incidents requiring intense physical restraint and the full moon. Reference: The aggressive behavior of individuals with intellectual disabilities is not affected by a full moon: a 17-year study (2015) 908,000 service calls to the police in a 8-year period: no relationship between calls for service and full moon. Reference: When the full moon rises over the Sunshine State: A quantitative evaluation of Queensland police calls (2017) 54,588 helicopter emergency medical services (HEMS) in a 1-year period: no significant increase in HEMS activations during full moon compared to control periods before and after the full moon. Reference: Full moons and Helicopter Emergency Medical Services (HEMS) activations in the United States (2022) 780 admissions and transfers to a Department of Psychiary in a 1-year period: chemical restraint used more often on full moon and new moon days than on control days. Reference: Does lunar synodic cycle affect the rates of psychiatric hospitalizations and sentinel events? (2021) Crimes committed indoors and outdoors in a 1-year period: moon illumination had no effect on total crime or indoor crime, but the intensity of moonlight had a positive effect on outdoor criminal activity. Reference: A hunter's moon: the effect of moon illumination on outdoor crime (2017) 1,853 instances of occupational violence and aggression in an emergency department in a 3-year period: no increase in occupational violence and aggression during full moon. However, the first quarter and third quarter moon phases did show increases in occupational violence and aggression. Reference: Lunacy in a tertiary emergency department: A 3-year cohort study of the association between moon cycles and occupational violence and aggression (2020)

Anxiety, Depression and Psychosis 782 patient records and 4,600 consultations in an 18-year period: no relationship between the phase of the moon and the number of times people contacted their doctors for anxiety or depression. Reference: Lunar cycle and consultations for anxiety and depression in general practice. (1997) 18,495 records from patients admitted to a psychiatric hospital in an 11-year period: admissions for psychosis were highest during the new moon and lowest during the full moon. Reference: Lunar madness: an empirical study (1977) 25,568 psychiatric emergency room visits in a 13-year period: visits increased near the first quarter moon and a decreased around the new moon and full moon. Reference: Human aggression and the lunar synodic cycle (1978) 8,473 psychiatric admissions in a 9-year period and 1,909 emergency psychiatric evaluations in a 1-year period: no relationship between admissions or evaluations and the phase of the moon. Reference: No effect of lunar cycle on psychiatric admissions or emergency evaluations (2006) The average number of contacts with psychiatric services in a 10-year period: no relationship between contacts and phase of the moon. Reference: Frequency of contact with community-based psychiatric services and the lunar cycle: a 10-year case-register study (1997) Number of psychiatric hospital admissions for schizophrenia in a 6-year period: highest during first quarter moon, followed by full moon and lowest at the new moon. Reference: Lunar cycle and psychiatric hospital admissions for schizophrenia: new findings from Henan province, China (2020) Agitation and aggression events in adult inpatients at a state psychiatric center in a 5-year period: no association between patient actions and lunar phase. Reference: Exploring the potential psychiatric implications of astronomical phenomena (2019) 62,203 patients with mental illness attending an emergency room in a psychiatric hospital in an 11-year period: no statistical difference in the number of visits during different moon phases. Reference: Lunar cycle effect on patient visit to psychiatry hospital emergency room: studying the 'Transylvanian effect' in an Islamic society (2013) 559 patients (ages 4-21 years old) who visited a pediatric psychiatric emergency department in a 3-year period: no statistical significance in the number of pediatric patient visits during a full moon and a non-full moon dates. Reference: Pediatric psychiatric emergency department visits during a full moon (2014) 1,857 patients presented to a psychiatric component of an emergency room in a 41-month period: no effect of lunar cycle on the number of psychiatric presentations. Reference: Psychiatric presentations during all 4 phases of the lunar cycle (2017) 7,153 behavioral occurrences in psychiatric patients at a mental health facility in a 7-year period: no significant relationship with lunar cycle. Reference: Don't blame it on the moon (2023) 7,844 emergency calls to a suicide prevention/crisis call center in a 2-year period: the highest number of total calls was during the new moon, not the full moon. When calls for suicide threats were analyzed, there were more calls during the first quarter of the moon and new moon. Reference: Moon phases and crisis calls: a spurious relationship (1977) 4,575 telephone calls to a crisis center in a 6-month period: no relationship between crisis center calls and moon phase. Reference: Lunar phases and crisis center telephone calls (1990) 36,268 calls to a crisis center in a 8-year period: no relationship between crisis center calls and moon phase. Reference: Investigation of periodicity in crisis intervention calls over an eight-year span (1979) 76,065 calls to a crisis center in a 4-year period: increased calls by females during the new moon period; decreased calls by males during the new moon period. Reference: Sex difference in response to stress by lunar month: a pilot study of four years' crisis-call frequency. (2003) 736 telephone counseling calls in a 4-month period: no relationship between calls and the moon phase. Reference: Psychological Reports, 35:752-754, 1974 100 admissions to a psychiatric hospital in a 3-year period: no relationship between hospital admissions and the phase of the moon. Reference: Lunar phases and psychiatric hospital admissions (1994) Visits to a psychiatric emergency department in a 5-year period: no statistical difference between the number of patients seen on full moon nights and non-full moon nights. Reference: Psychiatric emergency department visits on full-moon nights (2005) Anxiety and mood disorders, panic and suicidal ideation in patients in an emergency department in a 3-year period: no relationship between psychological disorders and the phase of the moon. Reference: Impact of seasonal and lunar cycles on psychological symptoms in the ED: an empirical investigation of widely spread beliefs. (2012) Administration of medications to treat delirium and agitation in 5,795 critically ill patients in a 2-year period: no difference in the administration of medication in lunar periods and no increase in the incidences of delirium and agitation during the full moon. Reference: Do moon phases or proximity influence the incidence of delirium and agitation in ICU patients. (2018)

Suicides 928 suicides in a 4-year period: suicides did not increase during the full moon. In fact, more suicides were noted during the new moon. Reference: Lunar association with suicide (1977) 897 suicides committed in a 3-year period: no relationship between suicides and the phase of the moon. Reference: Suicides and the lunar cycle (1997) 504 suicides committed in a 1-year period: no relationship between suicides and the full moon. Reference: The moon and suicide (1978) 383 cases of attempted suicide in a 1-year period: no relationship between attempted suicides and the phase of the moon. Reference: Attempted suicide and the lunar cycle (1991) 1,997 suicides in a 13-year period: suicides did not occur more often during the full moon. Reference: Human aggression and the lunar synodic cycle (1978) 4,190 suicides in a 58-year period: suicides had no relationship between suicides and the phase of the moon. Reference: Variation in suicide occurrence by time of day, day of the week, month, and lunar phase (1991) 3,054 suicides in a 6-year period: no relationship between suicides and lunar phase. Reference: Influence of lunar phases on suicide: the end of a myth? A population-based study (2005) 5,647 patients who attempted suicide in a one-year period: no significant difference between lunar phases and suicide attempts. Reference: Koyuncu, M., et al., Does lunar cycle influence suicide attempt?, J. Ann. Eu. Med., 7(1): 6-10, 2019. 1,187 cases of "self-poisonings" in a 1-year period: no relationship between self-poisonings and the phase of the moon. Reference: Self-poisoning and moon phases in Oslo (1986) 841 cases of "self-poisonings" in a 4-year period: self-poisonings did occur more often on the day of the full moon. Reference: Full moon and poisoning (1980) 184 cases of self-inflicted burns in a 20-year period: no relationship between self-inflicted burns and phase of the moon. Reference: Self-inflicted burns: a sporadic phenomenon (2004) 2,497 suicides in a 3-year period: no relationship between the number of suicides and the phase of the moon. Reference: Porkorny, A.D., Moon phases, suicide, and homicide, Am. J. Psychiatry, 121:66-67, 1964. 25,137 suicides in the United States in a 1-year period: no relationship between the number of suicides and the phase of the moon. Reference: Temporal variation in suicide and homicide (1979) 608 cases of suicides in a 2-yr period: no evidence of a relationship between suicide and lunar phase. Reference: Chaudhari, N.K. et al., Lunar phases and suicide - A prospective study, Int. J. Med. Tox. & Legal Medicine, 21:28-30, 2018. 65,206 completed suicides in a 36-year period: no relationship between the number of completed suicides and the phase of the moon. Reference: Not carried away by a moonlight shadow: no evidence for associations between suicide occurrence and lunar phase among more than 65,000 suicide cases in Austria, 1970-2006, (2008) 54,942 cases of suicide in a 42-yr period: no increase in suicides during the full moon quarter. Reference: Increased suicide risk among younger women in winter during full moon in northern Europe. An artifact or a novel finding?, (2022) 776 cases of suicide in a 5-yr period: increased number of suicides during the week of the full moon, with older individuals showing a stronger effect. Reference: Temporal effects on death by suicide: empirical evidence and possible molecular correlates, (2023) 2,605 cases (2111 male; 494 female) of suicide in a 23-yr period: no correlation between suicide and moon phase for male suicide victims; higher incidence of suicide during full moon in premenopausal women. A subsequent paper that reanalyzed these data found no effect of the full moon on the incidence of suicide and suggests that the prior results may be a false positive finding. Reference: Synodic lunar phases and suicide: based on 2605 suicides over 23 years, a full moon peak is apparent in premenopausal women from northern Finland (2020). 75 cases of suicide due to jumping off the Eiffel Tower in a 39-year period: no association with moon phases. Reference: The last jump: epidemiology of suicides at the Tour Eiffel (Paris) between 1950 and 1989 (2023)

Emergency Room Calls/Emergency Room Visits/Hospital Admissions Calls to a poison center monitored in a 1-year period: unintentional poisonings occurred more often during the full moon cycle. However, the number of calls due to intentional poison exposure (suicides/drug abuse) was significantly lower during the full moon and higher during the new moon. Reference: Lunar cycle and poison center calls (1983) 1,444 trauma victim hospital admissions in a 1-year period: no increase in hospital admissions during the full moon. Reference: Trauma and the full moon: a waning theory (1989) 22,828 trauma deaths in a 10-year period: no increase of the frequency of trauma deaths during full moon. Reference: Relation of the lunar cycle and trauma deaths in Tehran over 10 years (2023) 354,150 trauma patients treated in emergency unit in a 36-year period: slight decrease in trauma patients during the full moon. Reference: Relation of the weather and the lunar cycle with the incidence of trauma in the Groningen region over a 36-year period (2009) 1,178 major trauma patients admitted in a 4-year period to a hospital: no association between lunar phase and number or characteristics of trauma admissions. Reference: Impact of weather, time of day and season on the admission and outcome of major trauma patients (2016) 8,722 patients admitted for penetrating injuries at a major trauma center in a 6-year period: no significant difference in the number of admissions on full moon days compared to those on non-full moon days. Reference: The correlation between full moon and admission volume for penetrating injuries at a major trauma centre in South Africa (2021) 150,999 patients visits to the emergency department in 4-year period: no increase in total patient visits, ambulance runs, admissions to hospital on the day of the full moon. Reference: The full moon and ED patient volumes: unearthing a myth (1996) 3,468 emergency room visits and hospital admissions by people who intentionally took poison: visits and admissions were not different on days with full moons. Reference: Lunar cycle and poison center calls (1983) 368 cardiac arrests and 872 acute myocardial infarctions in a 6-year period: no relationship between cardiac arrests and myocardial infarctions and the moon phase. Reference: Lunar phases are not related to the occurrence of acute myocardial infarction and sudden cardiac death (2003) 15,985 patients consecutively hospitalized with an acute myocardial infarction (AMI) in a 23-year period: no association between the new moon, full moon, waning moon and waxing moon and the occurrence of an AMI. Reference: The influence of lunar phases on the occurrence of myocardial infarction: fact or myth? The MONICA/KORA Myocardial Infarction Registry (2012) 6,827 emergency department diagnosis of cardiopulmonary resuscitation in an 11-year period: no relationship between diagnosis and the full moon. Reference: Effect of lunar cycle on temporal variation in cardiopulmonary arrest in seven emergency departments during 11 years (2003) 8,415,412 emergency medical services activations (911 calls) in the United States in a 1-year period: no increase in 911 calls during the full moon compared to the number of 911 calls during other times of the month. Reference: Full moons are not associated with increases in emergency medical services (EMS) activations (911 calls) in the United States (2022) Thousands of rescue responses from several different agencies during at least 6 year periods: no significant differences in the number of rescue responses on full moon nights and full moon periods compared to other days. Reference: Rescue responses during a full moon and Friday 13th (2019) 29,552 cases of out-of-hospital cardiac arrest (OHCA) on full moon nights and 58,707 OHCA on control nights in a 12-year period: no significant difference in out-of-hospital cardiac arrest between full moon and control nights. Reference: Full moon and out-of-hospital cardiac arrest in Japan - Population-based, double-controlled case series analysis (2019) 7,570 cases of ST-elevation myocardial infarction in a 12-year period: no significant difference in ST-elevation myocardial infarction incidence or major adverse cardiovascular events across lunar phases.. Reference: Impact of lunar phase on outcomes following ST-elevation myocardial infarction (2019) 10,916 emergency cases in a 6-year period: no relationship between emergency cases and the full moon. Reference: The influence of lunar phenomena on the incidence of emergency cases (2003) 1,240 cases of myocardial infarction or sudden cardiac death in a 7-year period: no relationship between myocardial infarctions or sudden cardiac deaths and the full moon. Reference: Lunar phases are not related to the occurrence of acute myocardial infarction and sudden cardiac death (2003) 4,387 patients who died after being admitted to the intensive care unit in a 2 year period: no effect of the full moon on mortality of patients. Reference: Effect of the full moon on mortality among patients admitted to the intensive care unit (2014) 223 cases of epistaxis (nosebleeding) in a 1-year period: no relationship between the phase of the moon and the number of nosebleed cases. Reference: The rate of spontaneous epistaxis is not linked to the lunar cycle but shows seasonal variations (2014) 447 cases of gastrointestinal bleeding in a 2-year period: significant more admissions for gastrointestinal bleed on full moon days. Reference: Influence of the full moon on the number of admissions related to gastrointestinal bleeding (2004). A reanalysis of these data show no evidence of a relationship between admissions and the full moon Reference: No Evidence of purported lunar effect on hospital admission rates or birth rates (2015) 2,416 referrals for oral and maxillofacial emergencies in a 16-month period: no relationship between emergencies and the full moon. Reference: The moon and its relationship to oral and maxillofacial emergencies (2003) 54,457 trauma patients admitted to emergency rooms in three hospitals: no increase in admissions or in the severity of the injury during the full moon. Reference: The full moon and admission to emergency rooms (2004) 1,374,235 consultations in general practice offices in one year: small increase in the number of consultations six days AFTER the full moon. Reference: The effect of the full moon on general practice consultation rates (2000) 1,211 patients with odontogenic abscess (dental abscess) during a 12 month period: no relationship between odontogenic abscess and lunar phase. Reference: A dental myth bites the dust--no observable relation between the incidence of dental abscess and the weather and lunar phase: an ecological study (2015) 130 patients who suffered a rupture of an abdominal aortic aneurysm: significantly more ruptures during the waxing moon period. Reference: Lunar cycles and abdominal aortic aneurysm rupture (2004) 348 patients with an acute aortic dissection in a 9.5-year period: no significant influence of the full moon on the incidence of acute aortic dissection. Reference: Impact of meteorological conditions on the incidence of acute aortic dissection (2018) 1,642 patients with acute aortic dissection in a 31-year period: significantly higher incidence of type B dissection during the full moon phase. Reference: Chronologic and climatic factors of acute aortic dissection: Study of 1642 patients in 2 continents (2019) 212 cases of a ruptured intracranial aneurysem in a 10-year period: significantly greater risk of an aneurysm rupture during a new moon and a full moon compared to other lunar phases. Reference: Secular pattern of aneurismal rupture with the lunar cycle and season (2016) 166 patients admitted with a aneurysmal subarachnoid hemorrhage in a 5-year period: significantly more subarachnoid hemorrhages during the new moon phase. Impact of the lunar cycle on the incidence of intracranial aneurysm rupture: Myth or reality? (2008) 186 patients treated for a ruptured intracranial aneurysm in a 3-year period: no association between lunar phases and incidence of intracranial aneurysm. Reference: The association between lunar phase and intracranial aneurysm rupture: Myth or reality? Own data and systematic review (2017) 6,770 pediatric orthopaedic injuries during a 3-year period: no effect of the lunar phase on the rate of injuries. Reference: Environmental and temporal factors affecting pediatric orthopaedic injuries (2013) 112,749 patients who were admitted to the hospital for a stroke in a 10-year period: no association between moon phase and occurrence or in-hospital mortality. Reference: No association of moon phase with stroke occurrence (2018) 5,965 patients who suffered a stroke in a 4-year period: no increase in admissions for stroke during the full moon. However, more female patients were admitted during the new moon and than in the first and third quarters and fewer male patients were admitted during the new moon than in the first and third quarters. Reference: Sex differences in the effects of the moon on ischemic stroke incidence: new findings from Beijing, China (2020) 655 patients treated for an aneurysmal subarachnoid hemorrhage in an 8-year period: no relationship between moon phase and the incidence of aneurysmal subarachnoid hemorrhage, grade of neurological deterioration or amount of subarachnoid blood. Reference: Impact of the moon on cerebral aneurysm rupture (2013) 717 patients with an aneurysmal subarachnoid hemorrhage in an aneurysmal subarachnoid hemorrhage in a 13-year period: no relationship between lunar cycle and the incidence of aneurysmal subarachnoid hemorrhage. Impact of the lunar cycle on the incidence of aneurysmal subarachnoid haemorrhage: Myth or reality? (2009) 453 incidences of subarachnoid hemorrhage in a 17-year period: no relationship between lunar phase and subarchnoid hemorrhage incidence. Reference: Subarachnoid haemorrhage incidence pattern analysis with circular statistics (2024) 199 patients with urological pathology presented to the emergency department during a 1-year period: no significant association between lunar cycle and presentation of urological pathology presented. Reference: Lunar cycle, seasonal variation, and prevalence of emergency urological presentations: correlation or coincidence? -- A preliminary report (2021) 3,547 patients with urology related problems presented to the emergency department during a 2-year period: although full moons were associated with a higher number of urological emergencies, the trend was not significant. Reference: 'The Transylvania Effect' - Does the lunar cycle affect emergency urological admissions? (2008) 559 renal colic diagnosis during a 2-year period: no significant relationship between lunar phase and renal colic. Reference: Lunar phases and emergency department visits for renal colic due to ureteral calculus (2016) 1,500 patients who were seen in an emergency department for renal colic in an 11-year period: no relationship between lunar phase and the incidence of renal colic admissions. Reference: Lunar tractive forces and renal stone incidence (2011) 5,432 patients with vertigo in a 2-year period: no statistical relationship between lunar cycle and frequency of patient entries. Reference: Effects of the lunar cycle, seasons and the meteorological factors on peripheral vertigo (2022) 12,102 animals examined at animal emergency center in a 3-year period: no association between the full moon and number of examinations per day. Reference: The influence of the full moon on the number of accessions to an animal emergency centre (2007) 11,940 dogs and cats examined at a veterinary emergency center in an 11-year period: no difference in the number of daily emergencies on full moon days and non-full moon days. However, there was a small increase in the number of emergencies on grouped "fuller moon days" (during waxing gibbous, full moon and waning gibbous phases) compared to the number of emergencies on other days. Reference: Canine and feline emergency room visits and the lunar cycle: 11,940 cases (1992-2002) (2007) 1599 equine emergencies were seen in the field and 1558 equine emergencies treated in the hospital in a 7-year period: no significant influence of moon phase on caseload. Reference: Distribution of equine and food animal emergency caseload by time of day, day of week, time of year, holiday, and phase of moon at an academic ambulatory and referral hospital (2023) 147,295 emergency visits (103,669 dogs, 41,513 cats, and 2113 other species) to an animal clinic in a 16-year period: no increase in the number of emergencies on full moon days. Reference: Association of holidays, full moon, Friday the 13th, day of week, time of day, day of week, and time of year on case distribution in an urban referral small animal emergency clinic (2009)

Surgical Complications 2,411 patients who underwent pulmonary resection for lung cancer in a 30-year period: rate of intra-operative complications, post-operative morbidity and mortiality was not significantly affected by the phase of the moon. Reference: The dark side of the moon: impact of moon phases on long-term survival, mortality and morbidity of surgery for lung cancer (2009) 5,923 patients who received total knee arthroplasty in a 7-year period: no significant difference in revision-free survival or clinical scores of total knee arthroplasy when surgery performed on day of different moon phases. Reference: Moonlight surgery: no influence of moon phase or Friday 13th on outcomes of total knee arthroplasty (2023) 14,970 surgical patients in a 7-year period: no relationship between deaths and the phase of the moon in which surgery was performed. Reference: A double-blind, controlled clinical trial of homeopathy and an analysis of lunar phases and postoperative outcome (1998) 2.5 million patients who had hip and knee replacement operations in an 11-year period: no association between the risk of mortality and septic and aseptic complications after joint replacement surgery and the lunar phase of the day of the operation. Reference: Are postoperative complications of joint replacement correlated with the phase of the moon? An analysis of data from the medicare registry (2023) 782 patients (866 operations) observed for complications after surgery: no relationship of complications to the phase of the moon. Reference: Lunar phase does not influence surgical quality (2003) 924 patients observed for perioperative complications and outcomes from elective surgery for degenerative disc disease: the occurence of a full moon was not correlated with an increase in complications, re-do surgeries or unfavorable outcomes. Reference: The influence of lunar phases and zodiac sign 'Leo' on perioperative complications and outcome in elective spine surgery (2016) 278 patients who underwent living donor kidney transplantation: no effect of moon phase on patient survival, perioperative complications or early graft loss. Reference: Moon phases and moon signs do not influence morbidity, mortality and long-term survival, after living donor kidney transplantation (2017) 452 bladder cancer patients who had a a radical cystectomy (bladder removal) during a 12-year period: no relationship between the moon phase when surgery was done and surgical complications, the number of re-operations, or survival. Reference: Lunar phases and zodiac signs do not influence quality of radical cystectomy-a statistical analysis of 452 patients with invasive bladder cancer (2007) 555 patients who had post-operative nausea and vomiting: no correlation between the phase of the moon and occurrence of post-operative nausea and vomiting 24 hours after anesthesia. Reference: The influence of the weather and the phase of the moon on post-operative nausea and vomiting (2006) 27,914 consecutive patients during a 9-year period: no relationship between full moon phase and intraoperative blood loss or emergency frequency. Reference: Popular belief meets surgical reality: Impact of lunar phases, Friday the 13th and zodiac signs on emergency operations and intraoperative blood loss (2011) 16,965 patients who had cataract surgery during a 5-year period: no significant difference in the number of intraoperative complications with different moon phases. Reference: The influence of lunar phases on complications in cataract surgery: An analysis of 16,965 patients (2017) 18,760 patients who had surgery during an 8-year period: no statistical correlation between moon cycle and postoperative haemorrhagic complications. Reference: Relationship between lunar cycle and haemorrhagic complication rate in surgery (2017) 305 patients with primary hip arthroplasty: no effect of lunar phase on perioperative complications. Reference: Lunar phase does not influence perioperative complications in total hip arthroplasty (2012) 12,224 surgical patients in a 2-year period: lunar phases had no effect on post-surgical pain. Reference: Howling at the moon? The effect of lunar phases on post-surgical pain outcome (2014)

Sleep/Physical Activity Mood and sleep duration in 1 rapid cycling bipolar patient in a 3.3 year period: shorten sleep duration and more positive mood near the full moon and longer sleep duration and more negative mood near the new moon. Reference: Daily ratings of mood and sleep duration over 3.3 years are associated with the lunar illumination cycle in a rapid cycling bipolar patient (2021) 2,097 sleep recordings from 1,265 people show no relationship between sleep and phase of the moon. Reference: Lunar cycle effects on sleep and the file drawer problem. (2014) Subjective sleep quality of 2,125 people showed no relationship to the lunar phase. Also, no differences in EEG spectral analysis or diurnal cortisol levels with lunar phase. Reference: Bad sleep? Don't blame the moon! A population-based study. (2015) Physical activity, subjective sleep quality and time in bed of 1,411 teenagers do not vary by moon phase. Reference: Physical activity, subjective sleep quality and time in bed do not vary by moon phase in German adolescents. (2017) Sleep duration, moderate-to-vigorous physical activity and light-intensity physical activity of 5,812 children (ages 9-11 years old): sleep duration was shorter (1%, 5 min) during the full moon compared to new moon, but there were no differences in physical activity or sedentary time with moon phase. Reference: Are children like werewolves? full moon and its association with sleep and activity behaviors in an international sample of children (2016)

Births 3,706 spontaneous births during a 12-month period: no differences in the number of births for different moon phases. Reference: Labor ward workload waxes and wanes with the lunar cycle, myth or reality? (1998) 11,691 births during a 4-year period: no differences in the number of births for different moon phases. Reference: Human births and the phase of the moon (1979) 4,071,669 births during a 38-year period: no relationship between the number of births and the phase of the moon. Reference: Lunar cycle and the number of births: a spectral analysis of 4,071,669 births from South-Western Germany (2008) 6,725 births during a 7-year period: no relationship between the number of births, birth complications or gender of the baby and phase of the moon. Reference: The influence of lunar cycle on frequency of birth, birth complications, neonatal outcome and the gender: a retrospective analysis (2008) 564,039 births during a 5-year period: no significant differences in the frequency of births, route of delivery, births to multigravid women, or birth complications for the different phases of the moon. Reference: The effect of the lunar cycle on frequency of births and birth complications (2005) 167,956 births during a 6 year period: no significant correlation between the number of births and the phase of the moon. Reference: Birth rate and its correlation with the lunar cycle and specific atmospheric conditions (2005) 1,391 births and 48,492 emergency department contacts (3,741 of the contacts for psychiatric reasons) during a 9 month period: no statistically significant differences in births or emergency department contacts during full moon dates. Reference: The gravitational pull of the full moon to explain phenomenon: Superstition or science (2022)

Epilepsy/Seizures 109 patients in a 2-year period discharged from an epilepsy monitoring center: a significant increase in psychogenic nonepileptic events occurred during the new moon quarter. Reference: Effect of lunar phase on frequency of psychogenic nonepileptic events in the EMU (2016) 119 patients with psychogenic nonepileptic seizures in a 3-year period: no consistent relationship between full moon phase and the occurrence of psychogenic nonepileptic seizures. Reference: Effect of meteorological factors and lunar phases on occurrence of psychogenic nonepileptic seizures (2021) 199 patients with epilepsy in a 3-year period: no relationship between the lunar cycle and the frequency of epileptic attacks. Reference: The relationship between the lunar cycle and epileptic attacks and their treatment (2024) 1,710 patients with a first-ever unprovoked seizure in a 19-year period: first unprovoked seizures were not influenced by the lunar cycle. Reference: Revisiting an ancient legend: influence of the lunar cycle on occurrence of first-ever unprovoked seizures (2020) 1,979 patients with a emergency room visit due to febrile seizure or febrile seizure plus in a 13 year, 8 month period: no relationship between lunar cycle and onset or frequency of febrile seizures. Reference: Are there effects of lunar cycle on pediatric febrile seizure?: A single-center retrospective study (2005-2018) (2019) 1,571 epileptic seizures in a 1-year period: when the over brightness of the night is controlled for, there is no relationship between the fraction of the moon illuminated and frequency of epileptic seizures. Reference: Moonstruck? The effect of the lunar cycle on seizures (2008) 206 people with seizures in a 3-year period: no significant association between the total number of epileptic/nonepileptic seizures with lunar cycle. Reference: The influence of the full moon on seizure frequency: myth or reality? (2004) 184 patients admitted to hospital with status epilepticus in a 3-year period: higher number of admissions three days after a new moon and lower number of admissions three days before a new moon. Reference: Association of environmental factors with the onset of status epilepticus (2008) 409 cases of sudden unexpected deaths in epilepsy in a 1-year period: no association between the number of sudden unexpected death in epilepsy and the lunar cycle. Reference: Seasonality as a risk factor for sudden unexpected death in epilepsy: A study in a large cohort (2010) 110 patients with seizures in a 1-year period: significantly more seizures during the full moon period. Reference: Association of the meteorological parameters and epileptic seizures (2023) 2,507 seizures in cats and dogs in a 9-year period: no relationship between the number of seizures and phase of the moon. Reference: Canine and feline epileptic seizures and the lunar xycle: 2,507 seizures (2000–2008) (2011)

Drug Use/Overdose 1,182 drug overdose cases recorded in a 15-month period: no relationship between overdose cases and the full moon phase. Reference: Drug overdose and the full moon (1980) 949 cases of drug use (toxicology screenings) in a 1-year period: no relationship between drug use and the phase of the moon. Reference: Hospital-based toxicology: patterns of use and abuse (1990) 17,066 psychiatric inpatient treatment cases in an 11-year period: no relationship with admissions, discharge rates or length of stay of psychiatric inpatients with lunar phase. Reference: Is it the moon? Effects of the lunar cycle on psychiatric admissions, discharges and length of stay, Swiss Med Wkly, 149:w20070 (2019) 2,403 patients (drug abuse) and 10,501 patients (psychiatric illness, not drug abuse) admitted to an emergency department in a 7-year period: no relationship between admissions and the phase of the moon. Reference: Declining rate of substance abuse throughout the month (2001)

Accidents 246,926 traffic accidents involving property damage and 50,492 traffic accidents with non-fatal injuries in a 9-year period: no relationship was found between accidents and moon phase. However, this research did find that accidents of both kinds occurred more often on Friday and Saturday and on Halloween. New Year's Eve and Thanksgiving also had higher rates of traffic accidents involving property damage. Reference: Cyclical calendar and lunar patterns in automobile property accidents and injury accidents (1998) 2,382 fatal traffic accidents in a 13-year period: accidents were not higher during the full moon. Reference: Human aggression and the lunar synodic cycle (1978) 4,835 traffic accidents in a 4-year period: no relationship to the phase of the moon. However, there was an increase in the number of accidents that occurred in the summer and on weekends. Reference: Geophysical variables and behavior: LXXII. Barometric pressure, lunar cycle, and traffic accidents (1993) 200,545 traffic accidents in a 5-year period: no relationship to the phase of the moon for the number of accidents or the severity of the accidents. Reference: Geophysical variables and behavior: LXVIII. Distal and lunar variables and traffic accidents in Saskatchewan 1984-1989 (1992) 4,835 traffic accidents in a 4-year period: no relationship to the phase of the moon for the entire 4-year period. An increase in accidents was observed during summer months and on weekends. Also, for one year, the number of accidents was lowest during the full moon. Reference: Geophysical variables and behavior: LXXII. Barometric pressure, lunar cycle, and traffic accidents. (1993) 843,554 cases of traffic accidents that required emergency transportation over a 5 year period: significant increase in emergency transporation for males and people 40 years old or older on full moon nights, but no significant changes in emergency transportation on full moon nights for females or people under the age of 40 years. Full moon and traffic accident-related emergency ambulance transport: A nationwide case-crossover study. (2018) 13,029 motorcycle fatalities in a 40-year period: more motocycle fatalities on nights with a full moon compared to motocycle fatalities without a full moon. Reference: The full moon and motorcycle related mortality: population based double control study (2017) An excellent critique of the 2017 paper The full moon and motorcycle related mortality: population based double control study. Reference: Full moons and forking paths (2022) Medical staff "incidents" recorded in a 4-year period: no relationship to the phase of the moon. Reference: Don't pass the buck! the full moon is not responsible for an increase in the occurrence of untoward events in a hospital setting! (1979) 3,842 falls by hospitalized, adult patients in a 5-year period: no relationship to the phase of the moon. Reference: Are patient falls in the hospital associated with lunar cycles? A retrospective observational study (2005) 666,912 patients who suffered fall injuries in a 5-year period: more fall injuries in rural areas on full moon days, but no increase in the incidence of fall injuries on full moon days in metropolitan areas. Reference: Effects of weather and moon phases on emergency medical use after fall injury: A population-based nationwide study (2021) 1,184 injuries to professional soccer players during four consecutive seasons: no relationship between the phase of the moon and injuries. Reference: Lunacy revisited - the myth of the full moon: are football injuries related to the lunar cycle? (2018) 2,819 cases of unnatural deaths (suicide, homicide, accidents) during a 18.5 month period: no significant relationship between the number of unnatural deaths and moon phase. Reference: Guptal et al., Lunar Cycle and its Correlation with Unnatural Death in Different Age Group, Indian J. Forensic Med. Toxicol., 15:173-180 (2021)

Animal Bites 1,621 patients over 3-year period who were bitten by either a cat, rat, horse or dog: the incidence of animal bites was significantly higher around the full moon. Reference: Do animals bite more during a full moon? Retrospective observational analysis (2000) 1,671 patients over a 1-year period who were bitten by dogs: no relationship between the frequency of dog bites and the phase of the moon. Reference: Barking mad? Another lunatic hypothesis bites the dust (2000) 2,642 patients over a 3-year period who were bitten by dogs: no relationship between the frequency of dog bites and the phase of the moon. Reference: Modelling risk factors for injuries from dog bites in Greece: a case-only design and analysis (2003)

Other 14 young male Taekwondo athletes over 2 consecutive lunar months: no effect of lunar phase on explosive physical performance. Reference: Effects of lunar phases on short-term, explosive physical performance among young trained athletes (2018) 12 male Taekwondo athletes: no significant effect of moon phase on recovery test level, Y-balance test or reaction-time test. Reference: Does the moon cycle affect the physical endurance, balance, reaction-time, mood state and well-being in trained athletes? (2019)

Problems Studying the Lunar Effect Perhaps one of the first things that you notice about these studies is that the results are inconsistent. Some studies show that a particular behavior will occur more often during the full moon and other studies show no relationship between behavior and the full moon. This finding alone casts doubt on the theory that the full moon influences behavior. It may also be that experiments have been designed differently. For example, some studies include "full moon" behaviors that occur a few days before and after the full moon, while other studies include only those behaviors within a single day of the full moon. Selective Memory? Because many people believe that the full moon can influence behavior, experiments must be designed carefully to eliminate the possibility that people's beliefs will influence the data. For example, if people know that they are in an experiment which studies how the moon affects behavior, they may act in ways that change the results. It is possible that people have a "selective memory" for strange events that happen on the full moon; they remember strange incidents that occur during a full moon, but forget when these same things happen at other times. Correlation Does NOT Mean Causation It is also important to remember that studies that examine relationships between behavior and the phase of the moon determine only correlations. These types of studies determine if one set of numbers varies in a reliable manner with another set of numbers. If they do, then it can be said that a relationship exists. The existence of a relationship between two "variables" DOES NOT mean that one variable causes the other variable. For example, if you looked for a relationship between the number of points scored by a basketball team and the number of books checked out of a library on different days, you might find a significant relationship. This doesn't mean that the score of basketball games causes people to check out library books or that checking out library books causes the basketball team to score more points. The reason why these two activities vary in a similar fashion is completely unknown and untested. It just happens that the two measurements vary in a related fashion. In the basketball/library book example, the relationship could be caused by many things, maybe even by the weather. Maybe there was a lot of rain when the basketball scores and library books were counted. Perhaps the rain caused the basketball players to practice more (resulting in more points scored) and caused more people to visit the library (resulting in more checked-out books). Some experiments do show that on days with a full moon there is more abnormal behavior. However, many of these studies have been criticized because they were not performed properly. For example, some of these experiments: tested only a few people over a short period of time. did not analyze the data with proper statistical tests. did not take into account the day of the week on which the full moon occurred did not take into account whether the full moon occurred on a holiday or a weekend.

Although most experiments fail to show a relationship between the phase of the moon and abnormal behavior, the belief in the "lunar effect" is still strong among many people. Unfortunately, the occasional newspaper story that describes strange behaviors during a full moon only reinforces this myth.

Did you know?

The full moon appears once every 29.53 days. The distance between the moon and the Earth varies from about 221,438 miles (356,410 kilometers) to 252,681 miles (406,697 kilometers). The average distance between the moon and the Earth is 238,828 miles (384,400 kilometers). The diameter of the moon is 2,160 miles (3,476 kilometers). For comparison, the diameter of the Earth is 7,926 miles (12,756 kilometers). The circumference of the moon is 6,790 miles (10,927 kilometers). For comparison, the circumference of the Earth at the equator is 24,902 miles (40,075 kilometers). Sometimes there are two full moons in one month. It IS possible to have a month without a full moon, but this does not happen very often and it can happen only in the month of February. You will have to wait until February 2018 for the next month without a full moon. The surface gravity of the moon is 1/6 that of the Earth. The first lunar landing occurred on July 20 at 4:18 p.m. (EDT) when the Apollo 11 Lunar Module touched down on the moon at Tranquility Base (Sea of Tranquility). At 10:56 p.m., astronaut Neil Armstrong touch one foot to the moon's surface. (Source: NASA)

More information about the full moon and behavior: Do things get crazy when the moon is full? - from the Straight Dope The full moon and lunar effects - from the Skepdic's dictionary Chudler, E.H., The power of the full moon. Running on empty?, in Tall Tales about the Mind and Brain. Separating Fact from Fiction, edited by S. Della Sala, Oxford: Oxford University Press, 2007, pp. 401-410. Supermoons and Behavior

lunar phase

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