Morning sunlight can reset the body clock surprisingly quickly because outdoor light is vastly brighter than most indoor environments — but the popular five-minute rule isn’t a proven biological threshold, and window glass weakens the signal rather than blocking it.
Source ↗
👁 0
💬 0
Morning daylight is a powerful signal to the human circadian system, but popular advice often turns a continuous biological response into a stopwatch rule. The claim that exactly five minutes outdoors will “reset” everyone’s body clock is not an established threshold.
Outdoor light can be many times brighter than ordinary indoor lighting, even when the sky does not look dazzling. Light reaching the retina helps the brain estimate where it is in the day, and light delivered after the low point of
Outdoor light can be many times brighter than ordinary indoor lighting, even when the sky does not look dazzling. Light reaching the retina helps the brain estimate where it is in the day, and light delivered after the low point of
Comments (0)