Time-restricted eating, every day, for ten years.

What "intermittent fasting" means here

For this page, we mean sustained 16:8 time-restricted eating (TRE) — most calories within an 8-hour window, typically noon to 8 PM, with water and non-caloric drinks during the fasting window.

Other forms (5:2, OMAD, 24-hour fasts) have somewhat different physiological profiles. The decade-record story is closest to the 16:8 pattern, which is also the most-sustained version in adherence studies.

The face benefits

Sustained 16:8 produces measurable benefits that show in the face over years:

1. Improved insulin sensitivity — chronic glycation of collagen is one of the largest contributors to "aged" skin texture. IF reduces baseline glucose and insulin, which slows glycation. Over 10 years, the difference is visible.
2. Autophagy stimulation — extended fasting triggers cellular cleanup processes that maintain tissue quality, including in skin. Direct face-record studies are thin, but mechanism is well-documented.
3. Stable body composition — sustained IF makes overeating less likely (the eating window is constrained). Body composition stability across a decade reflects in face structure.
4. Lower inflammatory markers — sustained IF reduces CRP, IL-6, and other inflammatory markers. Face-record effects of chronic inflammation accumulate slowly; their reduction also accumulates slowly.

The face risk

Past age 40, IF carries a face-specific risk that isn't usually discussed: insufficient calorie intake combined with low protein intake leads to facial volume loss faster than chronological age would produce.

The pattern: an IF practitioner past 45, eating in an 8-hour window, often under-consumes total calories and protein without realizing it. The body compensates by metabolizing tissue. Facial fat — which provides the youthful "filled" look — is one of the early targets.

The result: a 10-year IF practitioner who didn't manage protein and calories carefully often shows a more "drawn" or "hollowed" face than peers. The skin tone is good (lower glycation), but the facial structure looks under-volumed.

The mitigation is straightforward but commonly missed:

• 1.2-1.6g protein per kg of body weight, daily
• Total calories at maintenance or slightly above (not deficit)
• The eating window has to actually accommodate the food

Done right, IF past 45 maintains both skin tone (benefit) and facial volume (avoiding the risk).

What the literature shows

IF research is voluminous but uneven. Cleaner findings:

• De Cabo & Mattson, 2019 (NEJM) — review of IF mechanisms across animal and human studies; mechanism stack is well-supported.
• Tinsley & Bounty, 2015 — meta-analysis of IF on body composition; weight loss similar to caloric restriction at matched energy.
• Wei et al., 2017 (Science Translational Medicine) — fasting-mimicking diet (similar mechanism) produced cardiovascular and metabolic improvements over months.

Long-term (10+ year) face-record studies don't exist. The mechanism stack predicts the effects above, and short-window human studies replicate them.

What "10 years" actually requires

Sustained 16:8 for a decade is not a small ask. Adherence drops sharply for most populations:

• Year 1: 60-70% of starters still doing it
• Year 3: ~40%
• Year 5: ~25%
• Year 10: ~10%

The pattern that survives 10 years tends to be a flexible 16:8 — strict on weekdays, looser on weekends, social meals included without guilt. Rigid IF (no breakfast ever, never eating outside the window) breaks more often.

For face-record purposes, the loose-but-consistent 16:8 pattern produces 70-80% of the benefits of strict IF without the adherence cost. That's likely the right target for most adults.

How Precog reads IF

Precog doesn't track eating windows directly — the slots are sleep, exercise, water. IF practitioners can use the journal note feature on each slot to track adherence informally.

The portrait responds to the underlying behaviors that IF affects (sleep quality, recovery, body composition stability) rather than to IF specifically. A user who does IF and tracks sleep + exercise + water consistently will see the cumulative benefits in the year-5 portrait.

Practical close

If you do IF now and have for years, the literature suggests you're probably benefiting on insulin sensitivity, inflammation, and body composition. Past 45, watch protein and total calories — face volume loss is the under-discussed risk.

If you're considering IF, the case is reasonable for face-record purposes but not extraordinary. Sleep, exercise, and hydration produce larger face-record effects with lower adherence cost. IF is a useful complement; not a foundation.

The 10-year mirror will tell you which version of the practice you actually maintained.