Howling at the Moon

Last week in yoga class one of the participants arrived looking very pregnant.  The baby was almost due and someone suggested that it would be born within the week because the moon was nearly full - more babies are born under a full moon.  When I hear statements like that I like to say, “Cite your sources.”  Since the studio is located mere blocks from a major university, people knew what I meant:  you can’t just go around throwing out presumed facts without providing footnotes, references or other evidence showing studies that have verified those facts.  Anything else is just hearsay.

It was not too difficult to find information from many reliable sources on the myth of the full moon.  This ABC article interviews a research associate professor from the University of Washington who has studied “more than 100 research papers on the purported effects of the full moon on human affairs.”  His findings are that the widely held belief has no basis.  Most studies disprove the myth and those that seem to support it have design problems, including inadequate sample size, improper use of statistical tools or failure to hold other effects constant.  In summary, well-designed studies have not supported this belief.

Another source describes a study in Canada looking for possible lunar effects on the frequency of visits to two emergency rooms for psychological problems.  “The results of their analyses revealed no link between the incidence of psychological problems and the four lunar phases.”

The myth gained popularity with the 1978 publication of psychiatrist Arnold Lieber's bestseller Lunar Effects: Biological Tides and Human Emotions.  He explained the effect on human psychology by proposing a gravitational pull theory.  The moon causes ocean tides and should have a similar effect on the human body, which consists in large part of water.  The problem with this view is that tides occur every day, not just on those days when more sunlight is reflected in our direction.  The brightness of the moon has nothing to do with gravity.  Researchers also found that the author tended to use only data that supported his theory, omitting other findings.  (As I noted last time, popular, as in bestseller, does not equal true.)

ABC further reports: “Studies have found that cops and hospital workers are among the strongest believers in the notion that more crime and trauma occur on nights when the moon is full. One 1995 University of New Orleans study found that as many as 81 percent of mental health professionals believe the myth.”  Another study in southwestern Pennsylvania found 69 percent of surgical nurses believed that a full moon led to more chaos and more patients, while only 23 percent reported themselves as being superstitious.

Trust me, saying “Cite your sources” does not make you the most popular guy in the room, even in yoga class where folks tend to be a little more mellow.  But if no one challenges these superstitions and outright falsehoods, America will become more ignorant and misled.  This is not the kind of critical thinking populace we genuinely need.

Whether the full moon has influence is really a trivial matter, but similar instances of misinformation that are passed along in the same way and accepted on faith can have deadly consequences, as when parents forego having their children vaccinated.