Timing is Everything: How To Sleep Better and Live Longer

Sarah Ann Macklin keeps this conversation on sleep, but not on the usual question of how many hours. The subject is where those hours sit, what puts them there, and why two people sleeping the same duration at different times of night can end up in very different metabolic and cognitive states.

Light does most of the setting, and Dr Panda's own discovery is central to why. He identified melanopsin, a blue light sensing protein produced by a small subset of retinal ganglion cells, as indispensable for aligning circadian rhythms to ambient lighting. Later work in human retina and with molecules that selectively block melanopsin established how much the quality, intensity and timing of light matter, for rhythm, for mood, for mental health, and even for recovery in hospital settings. Bright light late in the evening reaches that sensor at exactly the wrong hour.

The other half is the last meal of the day, and why eating close to bedtime competes with the body's overnight repair work. A practical listen for anyone whose sleep is adequate in length but poor in quality.