How you live and how you feel
Almost nothing about health is decided in one day: what counts is what repeats. Sleep is not just rest, it is when the brain fixes what was learned and clears waste, so studying and then sleeping badly throws away half the afternoon. Half an hour of movement a day lowers the risk of almost every long illness, and what best measures fitness is not peak pulse but how fast it comes back down. Sustained stress over months wears down defences and sleep, which is a different thing from being stressed for an hour. And addictive substances all work through the same place: they touch the circuit that rewards what is worth repeating, harder and faster than eating or hugging, and the circuit adjusts and asks for more.
Where this sits
This is where the ladder starts: nothing is needed before it.
Exercises from this rung
Generated by the app, from easiest to hardest
What does alcohol do to the body?
- it feeds the gut bacteria, which do not digest for you but nearly
- it lowers the risk of almost every long illness
- it makes learning worse: memory consolidates during sleep
- it is handled by the liver, and excess slowly replaces it with useless tissue
Why It is handled by the liver, and excess slowly replaces it with useless tissue. Almost nothing about health is decided in one day: what counts is what repeats, which is why small sustained things beat grand resolutions that last a fortnight.
easierBesides resting, what is sleep for?
- Consolidating what you learned during the day
- Emptying the stomach of what was left undigested
- Replacing the oxygen used during the day
- Lowering the brain's temperature after effort
Why While you sleep the brain replays the day and fixes part of it: studying and then sleeping badly throws away half the afternoon. Waste is also cleared from nervous tissue. That is why a short night shows up next day in attention before it shows up as tiredness.
in betweenWhat do addictive substances have in common?
- They are all processed in the stomach
- They all alter the heart's rhythm
- They are all of plant origin
- They all touch the brain's reward circuit
Why They all end up touching the same circuit, the one that rewards what is worth repeating. They do it harder and faster than eating or hugging does, and in time the circuit adjusts and asks for more to feel the same. That is why dependence is not a matter of willpower but of a system that learned something it needs to unlearn.
harder