Unfortunately, it is not “amore” that many of us feel when “the moon hits the sky” – it’s trouble sleeping. The super blue blood we’ve recently witnessed, along with actually every other full moon, disrupts our sleep architecture. This is not just me talking. There is scientific evidence to prove it.
We almost never observe a truly full moon. It only happens when the Earth, Moon and Sun are all in alignment. On January 31, you may have seen the rare “Super Blue Blood Moon lunar eclipse.” Though the name has an epic quality to it, it’s simply a total lunar eclipse during a Blue Moon (the second full moon in a month).
So, does our sleep actually worsen during a full moon?
In 2013, a Swiss scientist Christian Cajochen decided to find the answer. What he did was, he studied 33 adults over a three-year period. He invited them to a sleep lab, hooked them up to the EEG machine and measured their hormone levels. The findings?
Cajochen determined that a full moon greatly affects the quality of our sleep. “We found that around a full moon, the electroencephalogram (EEG) delta activity during NREM sleep, an indicator of deep sleep, decreased by 30%, the time to fall asleep increased by 5 min, and EEG-assessed total sleep duration was reduced by 20 min.” This means that a few days a month, we sleep worse by no fault of our own!
The Swiss study was one of the most comprehensive ones focusing on the impact of a full moon on our sleep. But it’s still missing the key to the puzzle – the answer to “why does this happen?”
The common sense kind of answer would be that a full moon makes it far brighter which makes it harder to sleep. That may make sense until we remember that the Cajochen study was conducted in a sleep lab, so the participants were deprived of any source of light. And yet in the course of three years, every time a full moon came, they slept worse than usual.
According to Cajochen: “(…) we rather think that the observed rhythm represents an endogenous, i.e., circalunar rhythm property, reminiscent of other endogenous rhythms such as the circadian (daily) and circannual (seasonal) rhythms.”
So in a way, the brightness may make sense but from a way broader perspective. If we imagine that hundreds of centuries ago, the moon was the only source of light during the night for our hunter-gatherer ancestors, and when it shined with its full force, it made the night quite different than usual. And that, in turn, may have been enough to interrupt their sleep. It’s also reasonable to assume that our sleep patterns evolved in harmony with the changing moon phases, so maybe, over time, we’ve developed this internal reaction to a full moon.
Unfortunately, no theory has been proven yet. For the time being, we just have to accept the fact, that a few days a month, our sleep may be compromised due to forces far greater than us.