Life Science

Does a full moon actually affect people’s behavior?

- Asks Sue from Long Island, N.Y.

March 31, 2008
Is the moon making us crazy? [Credit: <a href="">Stelios Kiousis</a>.]
Is the moon making us crazy? [Credit: Stelios Kiousis.]

I admit that New Yorkers are not known for their superior driving ability, but on this one night the drivers seemed especially erratic. People kept cutting me off. One guy sped right through a red light, barely missing a collision with the crossing traffic. And some genius, perhaps British but probably not, forgot that in this country we drive on the right side of the road.

I thought about what made this night particularly favorable for lunatic drivers compared to any other. It wasn’t St. Patrick’s Day, New Year’s or very late at night, so drunk driving didn’t seem to fit. Only when I got out of my car and looked up did I conceive a possible explanation: the full moon.

The legend of the full moon’s effects on human behavior has existed for centuries, popularized by the myth of the werewolf. The words “lunacy” and “lunatic” are derived from the same Latin root that gives us the word “lunar,” as people often attributed intermittent insanity to the phases of the moon. While many people believe the full moon influences behavior, scientific studies have found very little evidence supporting the “Lunar Effect.”

In 1978, University of Miami psychologist Arnold Lieber wrote the book The Lunar Effect: Biological Tides and Human Emotions. He argued that the moon influences day-to-day behavior and concluded that homicides increased during the full moon after analyzing Miami’s crime records. Similar crime studies during that same time period, however, found no such relationship.

Then, in 1986, researchers from the University of Saskatchewan in Canada combined the results of about 100 studies and found “no causal relationship between lunar phenomena and human behavior.” They discovered statistical flaws in many of the papers that claimed to find such a link. They even reanalyzed Lieber’s homicide data and found no correlation.

More recently, numerous studies have been conducted by intrigued researchers, with most attempts to blame the moon for everything from suicides to vomiting after surgery coming up empty.

So with all this evidence to the contrary, what makes the full moon lunacy theory still so popular? Perhaps it’s the media, who know people are more likely to read a crime story if some police officer blames it on the moon. Or maybe people just want to hold onto an urban legend that’s been around for hundreds of years.

A more scientific answer may be selective memory. If some bizarre murder or car accident occurs, people are probably more likely to remember it if it happened during the night of a full moon.

After reading up on some studies — including one from the authority on this topic, the University of Saskatchewan — I’ve decided that the full moon was not responsible for my experience on the road that night. Perhaps I selectively forgot the thousands of other times I encountered lunatic motorists. Though I have no scientific evidence to prove it (just years of experience), I’m going with the theory that New Yorkers are just really bad drivers.

About the Author



Agro India says:

Last 5 yrs me and my family are living under terror of moon. LITERALLY. Before that i use to love the sight of moon, would like to take it pictures and sing songs on moon, but since last 5 yrs i just hate moon. You wanna know why? Because 2-3 days prior to full moon or no moon, some thing terrible, unnatural, unexpected happens with us. Either there is tense situation at home, or my wife is total anger mood from 6.00 in morning to 2-3 days, if we try to control our emotions and avoid getting angry, then some home appliance gets automatically damaged, our meter would catch fire, my car meets with accident, and there is a long list. But yes, it happens always, always, always just prior to full moon or no moon. I get terrified looking at calender then these days starts approaching. And believe me its not by chance, am keeping record and observing the same thing since 5 long years, but cannot do anything about it. WHY THE HELL GOD MADE MOON

AB says:

There is absolutely an effect with the full moon. Cause in Islam our prophet ordered us to fast for 3 days of every month on the days of the full moon (the 13th, 14th, and 15th of the lunar month).


Mukta paul says:

So what is the solution….??

Annette says:

Parasites breed during full moon. They are active and lay more eggs in our bodies. That is the reason we are not ourselves during that time.

The solution is to start a long term parasite cleansing. The internet has thousands of articles on parasites in humans (we all have them).

They love sugar and starches, but hate fresh green food and coconut oil. There are many parasite cleanse supplements available in health stores. A parasite cleanse can last up to three years.

Good luck.

Mya says:

The full moon makes people moody, more aggressive, and changes their behavior. This is because the gravitational pull on this specific period changes direction temporarily. It changes the way our body fluids (water, not blood flow) move, changing the way we think. This is mostly obvious in people with disabilities like ADHD or ASD. The wave in the sea also change direction too.

Jacob says:

thank you :) I needed this for a project LOL.

James R.S. says:

I totally believe there is a correlation to the full moon and human behavior. My personal experience has always shown that the couple days before, and especially the day of the full moon two things always happen. First, the attitudes of my wife and myself are always on edge about everything. This can and does lead to frequent heated verbal altercations. The second thing actually is adverse to the first, we get more “attracted” to each other (if you get my drift) than we usually are. Lol! I guess that this shows that there is a silver lining to every cloud. Don’t get me wrong, there is no lack between us on the romantic side, that explains the kids lol, but it definitely gets stronger during the full moon. On a different note, when I was single, the full moon made the bar nights more productive actually. Which coincidently isn’t how I met my wife. That was a true blessing. A blessing still going after 16 years. I’m just saying I do believe the full moon changes us, regardless of the studies.

Charlie says:

I do believe there is a conection with the moon and the way people behave. I am a nightnurse in a care home for people with dementia and other head injuries. I have noticed that people become more aggressive and restless (even other nurses become more stressed and moody)on full moon nights. I was wondering is there a difference in the air pressure on full moon nights than other nights? Does the air pressure difference effect the people that have brain injury, dementia or just a certain type of brain? After all a slight change in air pressure can change a boiling point on a kettle. Be intresting to know if this is the case with full moon “madness” :-)

Damo says:

Brilliant read Sue. Most of your factual evidence that hits on superstition and theories appear to be backed up with the comments that followed. People tend to remember more when there was a marker at that time. The marker here being the Lunar Moon which you hit upon in your post. The seed was planted through thousands of years of superstition so it becomes natural for most to find evidence to support their belief behind it thus keeping the belief alive. For example, you probably wouldn’t notice a Purple Ford Mustang unless you bought one and started driving in it, then all of a sudden you see them every where. By the way, it’s you yanks who drive on the wrong side :)

Uhlizza says:

I am absolutely positive of the effects of the full moon on the mind of all living creatures. When I was younger, yes the bars would be a madhouse of fist fights and police arrests; I learned to stay away. I suffer and am disabled due to Panic Disorder and other problems stemming in and around this full moon in November was a supermoon, so they say the worst in 70 years (closest). I suffer greatly becoming so paranoid it is all I can do to leave the house, it arrived around 6:30 am today in my area, so am waiting till later on to go out and get dog food am absolutely exhausted from insomnia; and my Mastiff Bull Pit Mix suffered nightmares right before the full moon last night where she was crying so badly in pain or hurt sounding so sad, so forlorn, I woke her up from whatever nightmare she was having which she sunk back into but as the full moon passed her wicked dreams did not return. I however have some rest to catch up on afraid to sleep the day away though talk about proliferating the insomnia!

Stephanie says:

“Parasites breed during full moon. They are active and lay more eggs in our bodies. That is the reason we are not ourselves during that time.

The solution is to start a long term parasite cleansing. The internet has thousands of articles on parasites in humans (we all have them).

They love sugar and starches, but hate fresh green food and coconut oil. There are many parasite cleanse supplements available in health stores. A parasite cleanse can last up to three years.

Good luck.
Annette, January 27, 2016 at 6:28 am ”

Are you actually serious? I hope this is a joke.

Taffeta says:

I came to this site in search of a couple of answers. I believe that they are doing the study completely wrong. I’ve recently discovered that my birth sign, moon sign, and ascendant sign together makes me affected by the moon. Not everyone will experience this. But today, I noticed that my mood was a bit shifty and decided to look it up, but all of the studies are saying that its only a myth. I don’t believe it is a myth…only that the study is done wrong

jane says:

Superstitious or not, I believe my own experience. Confusion, paranoid, depression, panic attack, wanted to be alone, always happen to my love one during full moon, and just quickly disappears when the moon becomes out of sight. It greatly affects our relationship. But everything turns normal after full-moon has passed. My goal is to find out how can this be prevented to happen every full moon. It seems I can;t find any leads of solution online, because, many believed it is just a superstition.

Lonemuffun says:

i needed this for a project thoinks

Jim says:

In answer to Stephanie and Jane – No Joke it’s parasites!

We have a son who is confirmed to have both Helminth and smaller amoeba type parasites. Not only do they lay eggs and move during the moon cycles but they also secrete waste right into our bodies which have hormone like effects – like being high/drunk.

We are a nation too proud to think we could have parasites but then again maybe we trust those too much who inject us with things that shouldn’t be injected. A strong gut microbiome/flora will help prevent/cure this issue in most as well as parasite cleansing. Parents of Autistic children will relate to this video!

SMG says:

People try to say that things are “more memorable when there’s a marker like a full moon” but I had an aweful, out of the ordinary evening and was very moody/angry over the littlest things yesterday. A friend just mentioned the full moon to me (day after) which brought me to read about this online. I felt “different” yesterday and had zero awareness of a full moon. I think there’s a definite possibility the full moon influences somehow, we just don’t know yet.

there’s a ghost in my fridge

Chip says:

Yeah, today is a full moon and my medicine doesn’t work, lol

Andreas says:

I can definitely see the argument that we remember events on a full moon more than other times or at least correlate events to symbols. But it seems like every full moon my depression is much worse and I’m very moody. I feel a headache that makes me tense, get set off and I’m more irrational. I don’t believe in horoscopes but I wonder if our fluids can be effected by the moon like the tides are? Big bodies of water of course have much more mass and so would be effected by gravitational pulls easier, my question is could we be ever so slightly effected by this as well? I should probably research when high and low tides happen in the stages of the moon, it’s the orbit of the moon coming closer to the earth and not the angle of sun light shining on the moon… I digress. I’ll research it I suppose, if anyone had information on the subject let me know please.

AMPR says:

The full moon definitely affects human thinking and behavior. The gravitational waves make the water-content of your body become pressurized, making humans become hyperactive and moody. It does also increase your sex-drive too I’ve noticed, to the point where it can be almost uncontrollable. In my area, people seem to become totally over-ridden from the effects of a full moon, they’re like zombies practically, they don’t even recognize that they are feeling and acting different. They behave like hyperactive cracked-out circus clowns who just cannot control themselves unless their about to pass out. Everytime I see a full moon, I just know I’m a going to have a really angry bad day, and I’m going to be exhausted when it’s over. I don’t even bother trying to have productive dialogue with people during the full moon, because I know they’re not going to be thinking like their normal selves, it’s like talking to a caveman.
Basically the full moon increases your raw primal energy, and just intensifies whatever kind of mood you are already in. It also messes with the hormone flow in your body , producing a bizarre euphoric-like high/drunk feel. To me it seems the best way to overcome the energy of the full moon is simply being aware of it and it’s effects. If your aware, then you can automatically negate it’s effects with simple willpower.

Kitty says:

Yesterday I got into an argument with my roommate. She was belligerent and started yelling at me for no reason. I decided to stand up for myself and stand up to her. What a bully. I just realized it was during a full moon. I’m normally a very peaceful person. We had one other argument a month ago.. it might have been during the last full moon and it was definitely when mercury retrograde started. If full moons affect women’s monthly cycles and the tides of the oceans, people have to be pretty dense to not think it won’t affect human behavior. Also it’s rare if I fight with someone.

Charles says:

Not a very scientific article. Researchers found flaws? How were the flaws measured? By what standard?

chris says:

where is the video

cooper says:

Thanks I need that for a project

Adrianna says:

I believe all these comments are accurate. Full moon tonight and me and the hubby huge argument over stupidity. He has ADHD and real aggression during a full moon.

Diana says:

I worked in a counseling center. No one wanted a shift during full moon and erratic behavior increased during full moon as well as suicide calls.

Lara says:

People who mock astrology as delusional are low IQ, ignorant.

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