Women's menstrual cycles became irregular in 2010 because of the introduction of smartphones and artificial light at night.
Posted by The Charlie Kirk Show, Checked
- Sources
- 3 contradict3 support2 context
- Said
- 1 time·
- Confidence
- 50%
The Charlie Kirk ShowAug 5, 2026
The sources support that menstrual-cycle synchronization with the lunar cycle weakened after 2010, when LED lights and smartphones spread, and the researchers attribute this to artificial light. However, the studies measure loss of lunar synchrony rather than cycles becoming irregular, and the causal link is a hypothesis the authors state rather than an established finding.
A guest makes this claim. Listeners heard it, so it counts against the post, and on the guest's own record.
What was said
… We have some really interesting data that came out in around 2010 that showed women stopped cycling. Actually, that the research came out in 2022. It was done in 2010. That showed women cycled with the moon up until that time. What happened in 2010? We all got smartphones, and so women fell out of sync. Their menstrual cycles became irregular in 2010 because of this artificial light at night issue that we all have now. So, wait, wait, wait, wait, hold on. So smartphones broke women's menstrual cycle? It's a thing. It's a thing. There have been books written on this topic. Kidding. Wait, so just because women are, like, scrolling Instagram at night, that broke their cycles? …
The Charlie Kirk Show · · from the transcriptPost →What we found
Contradicts. The studies do not report that menstrual cycles became irregular; they report a change in coupling to the lunar cycle, with cycles still synchronizing with January's strong gravitational pull after 2010.[2][3][4]
Contradicts. The authors explicitly frame the artificial-light explanation as a hypothesis ("we hypothesize"), so the sources do not establish the 'because of' causal claim as fact.[2][3]
Supports. A 2025 Science Advances study of menstrual records found that cycles synchronized with the full and new moon before 2010 but that this entrainment was no longer detectable in pooled data after 2010, when artificial light at night increased markedly.[2][5][6]
Supports. The researchers relate the loss of synchrony to increasing exposure to LED light and screens, and the coverage attributes it to the spread of smartphones and LED night lights from 2010 onward.[4][6][7]
Context. Other research notes that smartphones and screens disrupt the circadian clock that regulates sleep and hormones, but this does not directly measure menstrual irregularity in 2010.[1][8]
Sources
8 sources: 1 fact-checker, 1 primary, 5 not rated, 1 tier 1
- 1How to stop doomscrolling in bed - AP Newsapnews.com · fact-checker · cited for: context
- 2Synchronization of women's menstruation with the Moon has ... - PMCpmc.ncbi.nlm.nih.gov · primary source · cited for: contradicts, supports
- 3Synchronization of women's menstruation with the Moon ...pure.amsterdamumc.nl · not rated · cited for: contradicts
- 4How Our Phones Messed With the Menstrual Cycle's Link to the Moonvice.com · not rated · cited for: contradicts, supports
- 5Synchronization of women's menstruation with the Moon has decreased but remains detectable when gravitational pull is strongscience.org · tier 1 · cited for: supports
- 6Smartphones and synchronisation between menstrual cycle and lunarsciencemediacentre.es · not rated · cited for: supports
- 7Artificial light weakens menstrual cycle's natural synchronization ...medicalxpress.com · not rated · cited for: supports
- 8Impact of light on the human body with particular emphasis on women's reproductive healthjournals.viamedica.pl · not rated · cited for: context
Where this claim was made
Said in 1 published post
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