Blood Moon total lunar eclipse 2021: Is it true the full moon can affect human behaviour?
Is there any truth to the ancient theories about how the moon impacts our moods?
Look outside your window come nightfall this evening and you’re in for a treat.
A stunning Flower Supermoon is due to illuminate our desert skies tonight – a full moon that’s at the closest point in its orbit around the Earth and therefore bigger and brighter than regular moons.
But take your eyes away from this celestial light show and peer around back on solid ground for a moment. Do you see anything… peculiar? Is everybody behaving as normal? Are you feeling at all out of the ordinary yourself?
Because legend has it that a full moon can affect human emotions - disrupting sleep, unsettling moods and “making men mad” according to Shakespeare’s Othello.
And a Supermoon – being closest to the Earth – is said to be one of the most powerful full moons of all…
Lunar folklore
From myths about werewolves to the etymology of the word ‘lunatic’ (which stems from the Latin ‘lunaticus’ meaning ‘moonstruck’), folklore about the full moon’s impact on human behaviour can be traced back thousands of years.
Greek philosopher Aristotle reasoned that, since the moon controls the sea’s tides, it must also have an impact on the water in our bodies, and belief in “the moon effect” – whereby humans would supposedly morph into werewolves or vampires during a full moon - was widespread throughout Europe during the Middle Ages.
But it’s not only an ancient belief. Even in modern times it’s common to hear people blame the moon for a road-user’s erratic driving or a child’s tantrum. In fact, a 2017 study on ‘Psychiatric Presentations During All 4 Phases of the Lunar Cycle’ cited the fact that 81% of mental health workers claim they’ve noticed a relationship between human illnesses and a full moon in their own clinical experience.
Some people even blame the extra gravitational pull of a full moon or Supermoons for extreme weather events such as tsunamis and earthquakes.
What the science says
As intoxicating as it can be to believe in the mystical, mind-altering magic of the moon, the science does not back this up.
There have been many studies on the impact of the moon on human behaviour – looking at crime rates, as well as mental and physical health statistics – and while there have been certain links found in discrete areas, there is no rigorous trend to prove that the full moon really impacts our emotions.
One of the most prevailing myths is that the full moon is connected with unusual human behavior – people’s emotions being thrown off kilter, leading to mental illness or aggression.
So researchers in a 2017 study analyzed A&E records at a 140-bed hospital, but they found that people visiting the emergency room because of a psychiatric condition remained roughly the same during all four phases of the moon.
Meanwhile 2006 review of more than 10,000 medical records from different facilities found the same thing: no relationship between the full moon and the number of psychiatric or mood disorder hospital visits.
“The full moon does not have behaviour changes on humans,” says Sheeraz Ahmed, operations manager at Dubai Astronomy Group.
“It is simply a myth and there is not any scientific evidence to support it. If someone were to do a crime during a full moon and use that as an excuse it would not hold in court for example.”
Ahmed says that the logic that the moon affects the ocean’s tides and therefore might have an impact in the water in the human body or brain is flawed: “The amount of water in the human body compared to that in the open ocean is insignificant,” he says.
Ahmed adds that although the Supermoon’s proximity to the Earth does have a very small impact on the tides compared to regular moons, it is insignificant. “The water level may rising by about 5cm at most, so it’s not like it would cause a natural disaster because of the Supermoon. We also have Supermoons all year round - at least twice to three times per year - and if you didn’t know this was a Supermoon just by looking at it you wouldn’t be able to tell either.”
The full moon’s impact on pregnant women
Pregnancy is already fertile ground for old wives’ tales, and of course the moon does not get left out. Many cultures link the lunar cycle with a woman’s monthly menstrual cycle, and the regular waxing and waning of the round moon led to many ancient peoples perceiving the moon as feminine entity that ‘gives birth’ to the full moon every month.
Even in modern times you might hear nurses or midwives joking about maternity wards becoming busier over a full moon, and it is a widely held belief that the invisible force of the moon can induce labour and lead to higher birth rates.
However the research does not back this up. A study published in the American Journal of Obstetrics and Gynecology in May 2005 examined birth certificate data for nearly 570,000 births over 67 moon cycles from 1997-2001. There was no significant difference in the frequency of births, route of delivery, or birth complications across 8 difference phases of the moon. A French study around the same time analysed the dates of 14.5 million births in Europe and also discovered no patterns, and many other studies before and since have attempted and failed to find any link between the moon and birth rates.
Nevertheless, it is known that in many marine species and some land-based animals reproductive behavior is synchronized with a particular phase of the lunar cycle (often full or new moon), and a fascinating January 2021 study published in ‘Science Advances’ did find a link between the moon and women’s menstrual cycles.
Analysing long-term menstrual recordings of individual women with distinct methods for biological rhythm analysis found that women’s menstrual cycles with a period longer than 27 days were intermittently synchronous with the Moon’s luminance and/or gravimetric cycles. “With age and upon exposure to artificial nocturnal light, menstrual cycles shortened and lost this synchrony,” says lead study author Helfrich-Förster of the Julius-Maximilians University of Würzburg, Germany. “We hypothesize that in ancient times, human reproductive behaviour was synchronous with the Moon but that our modern lifestyles have changed reproductive physiology and behaviour.”
“We hypothesize that in ancient times, human reproductive behaviour was synchronous with the Moon but that our modern lifestyles have changed reproductive physiology and behaviour.”
The lunar impact on children’s behaviour
Many a mother will claim to be able to tell it’s a full moon without even tracking the sky simply because of her children’s behaviour – more sibling arguments and stroppy meltdowns? It must be the moon.
So much so in fact that a team of researchers led by Dr Jean-Philippe Chaput from the Eastern Ontario Research Institute set out in 2016 to study the effect of the full moon on sleep and behaviour in children.
Following almost 6,000 children from all socio-economic backgrounds, living across five continents, many variables were considered - including age, gender, parents’ background, sleep duration and level of physical activity.
The researchers recorded specific activities and behaviours of the children over a 28-month period. All the kids were observed on the same days, which included an equal number of three lunar phases: full moon, half moon and new moon.
And the results? It seems those meltdowns might simply be down to your children’s personalities, as the study team found that no activity or behaviour was significantly affected by the full moon.
Apart from in one key aspect: sleep. Participants slept five fewer minutes on nights when the moon was full.
“Our study provides compelling evidence that the moon does not appear to influence people’s behavior,” Dr Chaput told Nationwide Children’s. “The only significant finding was 1% less sleep during the full moon, and this is largely explained by our large sample size, which maximizes statistical power. Overall, I think we should not be worried about the full moon. Our behaviors are largely influenced by many other factors like genes, education, income and psychosocial aspects… rather than gravitational forces.”
Where the moon might affect us
This link between the moon’s increased physical brightness when it is full and changes in sleep pattern seems to be the most convincing aspect of the lunar impact on humanity.
A 2013 study conducted under the highly-controlled conditions of a sleep laboratory found that people took five minutes longer to fall asleep on average, and slept for 20 minutes less overall, around a full Moon, compared to during the rest of the month – even though they weren’t exposed to any moonlight. Measurement of their brain activity, meanwhile, suggested that the amount of deep sleep they experienced dropped by 30%.
Perhaps the most convincing evidence of any link between moon and mood is in bipolar patients. A 2018 study examined 17 people whose bipolar disorder tended to switch rapidly from depression to mania, according to Healthline.
The study showed that the circadian pacemaker (a small group of nerves) in these individuals became synchronized with lunar patterns. This caused changes in their sleep that then triggered a shift from depression symptoms to mania symptoms.
There is also some evidence that the lunar cycle can impact blood pressure, but another study on male athletes concluded that there was no relationship between the moon’s movements and human cardiovascular systems.
All in all, the evidence on the impact of the moon on humans is as conflicting and fickle as the Moon itself. While the prevailing science debunks any link whatsoever, there are enough disparate slices of evidence to retain some element of mystery. And really, that’s what the primal part of ourselves wants from the moon. As Dubai Astronomy Group operations manager Sheeraz Ahemd says: “It’s almost a placebo effect - it's all about what you want to believe.”