Definition
A caloric deficit means consuming less energy than your body expends, forcing it to use stored fat (and some muscle) for fuel. A sustainable cut runs at 15–25% below TDEE — about 0.5–1% of bodyweight lost per week — paired with high protein and resistance training to preserve muscle.
Real questions
How big should my deficit be?
300–500 calories below maintenance for most people. Larger deficits burn muscle, crash recovery, and crash adherence.
Why am I not losing weight in a deficit?
Either calories are underreported, TDEE is overestimated, water retention is masking fat loss, or NEAT has dropped. Track honestly for 2 weeks and the answer usually appears.
Stack with
Put it to work
Coach Foster builds your program around caloric deficit and the rest of the fundamentals, shaped to your body and your week.