View bright light, ideally sunlight, within 30 minutes to an hour of waking, ideally every day or most days, to set your master circadian clock and coordinate all body cells. This practice is the primary signal for setting your body’s master clock, which in turn coordinates all cells and systems, leading to optimized health, energy, and sleep.
Absolutely dim the lights in the evening and late hours to avoid inhibiting the release of melatonin, which is crucial for transitioning into sleep. Light powerfully inhibits melatonin release, and maintaining dim lighting helps your body naturally prepare for sleep.
Avoid exposure to bright lights between approximately 10 PM and 4 AM to prevent disruption of your body’s melatonin production and circadian rhythm. Consistent bright light exposure during these hours can significantly disrupt your system, leading to issues with mood and sleep.
When addressing health or other issues, identify and manipulate “upstream levers” because getting them right can automatically resolve many “downstream consequences.” This approach can lead to widespread positive effects across various bodily systems and functions.
Do not attempt to get your morning light exposure through a window or car windshield, as the filtration of light wavelengths will make it approximately 50 times less effective. Windows and windshields block crucial wavelengths of light needed to properly activate the circadian clock setting mechanism.
Adjust the duration of your morning light exposure based on conditions; a very bright day might only require 1-2 minutes, while an overcast day might require up to 30 minutes. The clock mechanism is a “slow integrator” that counts photons over time, meaning less intense light requires longer exposure to achieve the same effect.
If you miss a day of morning light exposure, aim to get twice as much time outside the following day to compensate. The circadian clock mechanism is a slow integrator, meaning it accumulates light energy over time, so increased exposure can help reset it after a missed day.
If you wake up before the sun rises, turn on as many bright artificial lights as possible indoors, but then transition to outdoor light exposure once the sun is out. This helps kickstart your circadian system when natural light isn’t available, preparing it for the full effect of sunlight later.
If you lack access to sunlight, use a low-cost “blue ring light” (like those used by YouTubers) at your breakfast table or while working in the morning to simulate bright light exposure. This artificial light source is bright enough to help activate the circadian system when natural sunlight is unavailable.
Dim lights in the evening only as much as needed to safely move about and perform evening activities, rather than trying to achieve complete darkness. The goal is to reduce light exposure to support melatonin release without causing unnecessary paranoia or safety concerns.
Do not panic if you occasionally violate light exposure guidelines (e.g., turning on bright lights at night), as the circadian system is a slow integrator and consistent disruption is the main problem. The system is robust enough to handle occasional deviations, but consistent negative behaviors will significantly disrupt it.
Never stare directly at any light, artificial or sunlight, that is so bright it causes pain, as your blink reflex exists for a reason. This is a safety measure to protect your eyes from damage.