# menstruation & the moon **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [September 29, 1999, 9:10pm UTC](https://boards.straightdope.com/t/menstruation-the-moon/239 "1999-09-29T21:10:00Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![k.monahan](https://avatars.discourse-cdn.com/v4/letter/k/df705f/32.png) [@k.monahan](https://boards.straightdope.com/u/k.monahan)\ **Post date:** [September 29, 1999, 9:10pm UTC](https://boards.straightdope.com/t/menstruation-the-moon/239/1 "1999-09-29T21:10:00Z")
it may seem way out in left field, but i remember hearing that an experiment was conducted wherein women were isolated from artificial light (i.e., for the purposes of the experiment they used sunlight, skylights inside, went to bed w/ the sun, i’m assuming, etc.) for several months, and that a high percentage of the women’s cycles adjusted to begin with the full moon. also, i was told, the women were isolated from each other to control for the well-known convergence of menses amongst co-habiting women. has anyone heard of this phenomenon or study, and, if so, why would artificial light inhibit some “natural” cycle? ---
**Author:** ![k.monahan](https://avatars.discourse-cdn.com/v4/letter/k/df705f/32.png) [@k.monahan](https://boards.straightdope.com/u/k.monahan)\ **Post date:** [September 29, 1999, 9:13pm UTC](https://boards.straightdope.com/t/menstruation-the-moon/239/2 "1999-09-29T21:13:00Z")
Oh, i wish i had taken a moment to look in the previous topics. sorry to be repetitive! ---
**Author:** ![JillGat](https://avatars.discourse-cdn.com/v4/letter/j/9fc29f/32.png) [@JillGat](https://boards.straightdope.com/u/JillGat)\ **Post date:** [September 30, 1999, 12:36am UTC](https://boards.straightdope.com/t/menstruation-the-moon/239/3 "1999-09-30T00:36:00Z")
No big deal. If you really are humiliated and embarrassed, though, I’d be happy to delete your message… ---
**Author:** ![tracer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tracer/32/20578_2.png) [@tracer](https://boards.straightdope.com/u/tracer)\ **Post date:** [October 1, 1999, 8:35pm UTC](https://boards.straightdope.com/t/menstruation-the-moon/239/4 "1999-10-01T20:35:00Z")
Hey, don’t be shy, k.monahan! None of the posters in the other menses/moon thread in this Forum even _mentioned_ the experiment you just talked about. It sounds like exactly the kind of experiment I was hoping for, as a matter of fact. Do you know who did this experiment, when it was done, etc., so that I (and everyone else) could look the results up? ---
**Author:** ![k.monahan](https://avatars.discourse-cdn.com/v4/letter/k/df705f/32.png) [@k.monahan](https://boards.straightdope.com/u/k.monahan)\ **Post date:** [October 4, 1999, 8:36pm UTC](https://boards.straightdope.com/t/menstruation-the-moon/239/5 "1999-10-04T20:36:00Z")
unfortunately (and too commonly!) i don’t recall the specifics of where i heard about this experiment…which probably qualifies it for the inesteemed realm of the unverifiable–i was actually hoping that someone may have heard of it, and remembered the source better than me. thanks for your kind words though, tracer ---
**Author:** ![Kyberneticist](https://avatars.discourse-cdn.com/v4/letter/k/dc4da7/32.png) [@Kyberneticist](https://boards.straightdope.com/u/Kyberneticist)\ **Post date:** [October 4, 1999, 10:47pm UTC](https://boards.straightdope.com/t/menstruation-the-moon/239/6 "1999-10-04T22:47:00Z")
Well, the opening message on the other thread mentioned light cues. Given that a few places in this world are still hunter/gatherer (New Guinea in places, parts of Africa, a few in Australia) why not do a survey there? ---
**Author:** ![tracer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tracer/32/20578_2.png) [@tracer](https://boards.straightdope.com/u/tracer)\ **Post date:** [October 6, 1999, 6:26pm UTC](https://boards.straightdope.com/t/menstruation-the-moon/239/7 "1999-10-06T18:26:00Z")
Why not? Those darned campfires and hunting torches, that’s why. Damn you, Prometheus! * * * The truth, as always, is more complicated than that. ---
**Author:** ![Rocket](https://avatars.discourse-cdn.com/v4/letter/r/e79b87/32.png) [@Rocket](https://boards.straightdope.com/u/Rocket)\ **Post date:** [October 9, 1999, 5:02am UTC](https://boards.straightdope.com/t/menstruation-the-moon/239/8 "1999-10-09T05:02:00Z")
I remember an experiment conducted similar to the one k.monahan mentioned. A women was isolated (in a cave I think), without any natural light or any timekeeping devices. I seem to recall that the conclusion was that there was no “natural cycle”. She tended to have longer periods of activity, followed by shorter periods of rest. When she was removed from the experiment she was way off in her estimate of how long she had been isolated. Does anybody else remember this experiment? In my estimation it was about 25 years ago. A comment related to the post regarding women menstruating only 3 to 4 times a year. Isn’t this a defense mechanism related to starvation. The women would not release eggs for fertilization if there were not enough food available to sustain herself, not to mention the unborn child. ---
**Author:** ![AuraSeer](https://avatars.discourse-cdn.com/v4/letter/a/c2a13f/32.png) [@AuraSeer](https://boards.straightdope.com/u/AuraSeer)\ **Post date:** [October 9, 1999, 5:54am UTC](https://boards.straightdope.com/t/menstruation-the-moon/239/9 "1999-10-09T05:54:00Z")
It is true that starvation will suspend the menstrual cycle. Severely anorexic women often do not have periods at all. * * * Laugh hard; it’s a long way to the bank.