2024-11-28
38 分钟Welcome to Huberman Lab Essentials, where we revisit past episodes for the most potent and actionable science based tools for mental health, physical health and performance.
I'm Andrew Huberman and I'm a Professor of Neurobiology and Ophthalmology at Stanford School of Medicine.
Today is episode three of the podcast and it is Office Hours.
Office hours.
As many of you know, it's where students come to the office of the professor, sit down and ask questions requesting clarification about things that were confusing, or to simply go down the route of exploring a topic with more depth and detail.
Somebody asked, what is the role of moonlight and fire?
I'm presuming they mean fireplace or candle or things of that sort.
In setting circadian rhythms, is it okay to view moonlight at night or will that wake me up?
Will a fire in my fireplace or using candlelight be too much light?
Great question.
Turns out that moonlight, candlelight and even a fireplace, if you have one of these roaring fires going in the fireplace, do not reset your circadian clock at night and trick your brain into thinking that it's morning.
Even though if you've ever sat close to a fireplace or even a candle, that light seems very bright.
And there are two reasons for that that are very important.
The first one is that these neurons in your eye that I discussed in the previous episode, these melanopsin ganglion cells, also called intrinsically photosensitive ganglion cells, those cells adjust their sensitivity across the day and those cells respond best to the blue yellow contrast present in the rising and setting sun, so called low solar angle sun, also discussed in the previous episode.
But those cells adjust their sensitivity such that they will not activate the triggers in the brain that convey daytime signals when they view moonlight, even a full moon, a really bright moon or fire.
Because we talked about just how crucial it is to avoid bright lights between the hours of about 10pm and 4am except when you need to view things for sake of safety or or work or so and so forth.
I also received a lot of questions about red light.
In principle, red light will not stimulate the melanopsin retinal neurons that wake up the brain and circadian clock and signal daytime.
However, most of the red lights, in particular the red lights that come on these sheets of these products that people are supposed to view them in order to access a number of health effects, those are way too bright and would definitely wake up your body and brain.
So if you're thinking about red light for sake of avoiding the negative effects of light later in the Day and at night, then you want that red light to be very, very dim, certainly much dimmer than is on most of those commercial products.