Eight hours, every night, for ten years.

What 8 hours produces

Aging happens regardless. The face you have at 50 is not the face you have at 30, no matter what you sleep. What 8 hours buys you is unindebted aging — the shape of the face changes for the same biological reasons everyone's does, but without the additional layer of debt that chronic restriction stacks on top.

The visible effect:

• Skin elasticity tracks normal age curve.
• Eye structure ages with peer baseline.
• Recovery from minor illness fast.
• Cumulative cortisol exposure low.
• No measurable chronic-deficit drift.

You will look your age. You will not look older than your age.

Why this is worth describing

It sounds boring. It is not.

The default modern adult is sleep-restricted in some chronic form. The "rested 8-hour adult" is rarer than the literature implies. Most people who think they sleep 8 hours actually sleep 7 or less, and most people who sleep 7 do so under mild restriction.

Knowing what un-debted aging looks like — and that it is the result of an unsexy, repeated, unglamorous baseline behavior — matters. It is not a luxury. It is the floor.

The mirror, in this case

If you actually sleep 8 hours and have done so for a decade, Precog's portrait at 10 years will look like you, plus 10 years. No surprise twist. No structural debt to surface. The mirror is just confirming what the body has been telling you in less visible ways.

The interesting case is when you think you sleep 8 hours and the portrait doesn't quite agree. That is the value: the calibration. Sleep tracking is famously bad at distinguishing 7.5 from 8.0 from 7.0. The face, over years, is more honest.