Cutting

Cutting is the term used in fitness culture for a deliberate, time-bounded caloric deficit aimed at reducing body fat. The vocabulary comes from bodybuilding but has diffused into general consumer tracking and coaching. A cut is not just "being in a deficit" — it implies structure: start date, target body-composition change, planned end date, and a recovery plan afterward.

The typical structure

• Duration: 8–16 weeks, sometimes run in blocks separated by diet breaks.
• Deficit size: 10–20% below maintenance for most users; 20–25% for short aggressive cuts.
• Protein: 1.6–2.2 g/kg bodyweight, occasionally higher in very lean trained individuals.
• Training: resistance training maintained (not reduced) through the cut; cardio added as needed for additional deficit.
• Rate: 0.5–1.0% of bodyweight per week is a widely-cited upper bound for fat-loss-dominant change.

What goes wrong

Three recurring failure modes:

• Deficit too aggressive. Under 1,500 kcal/day (or below 25% of predicted maintenance) and the adaptive-thermogenesis hit plus lean-mass loss plus adherence failure typically erase any gain over a moderate deficit.
• Protein too low. Cutting on 1.0 g/kg protein routinely produces a body-composition outcome that looks like "small weight loss with no visual change" because too much of the loss was lean mass.
• Cut too long. Past 16–20 weeks of continuous deficit, adaptive thermogenesis, cortisol elevation, and appetite-hormone dysregulation combine to make continued progress hard and rebound likely.

Diet breaks and refeeds

Structured diet breaks (1–2 weeks at maintenance) every 6–12 weeks of cutting partially reverse adaptive thermogenesis and restore leptin toward baseline. Refeeds (single high-carb days) have less robust evidence but are widely used. The evidence supports diet breaks as a sustainability tool; it is more mixed on whether they produce a better body-composition outcome at a fixed calendar duration.

How tracking apps handle cuts

Consumer apps typically expose "Goal: lose weight" with a per-week rate selector. Under the hood, this sets a daily caloric target equal to maintenance minus the appropriate deficit. Adaptive apps (MacroFactor, MyFitnessPal premium) recalculate weekly based on weight-trend data. Non-adaptive apps stick with the original number, which will drift away from reality as the cut progresses and adaptive thermogenesis reduces actual maintenance.

Ending a cut well

The transition out of a cut ("reverse dieting") is a separate discipline. A reasonable default: raise intake by 100–200 kcal/week back toward estimated maintenance over 3–6 weeks, with continued weight tracking. Jumping from 1,800 kcal/day directly to 2,600 will produce a multi-pound water-and-glycogen rebound that feels like fat gain but isn't.