ARC guide
Why a Calorie Deficit Might Not Be Working
If the scale is stuck, check the estimate, the logging, and the rate — before cutting harder.
Direct answer
A “deficit” only works if intake is actually below expenditure. Most stuck cuts are a mismatch between estimated maintenance, logged food, and a rate that is either too small to see or too large to hold.
Key takeaway
Do not automatically lower calories. First ask whether maintenance was estimated, whether intake is measured, and whether the planned rate is visible over two to four weeks.
Maintenance is an estimate
Mifflin-St Jeor plus an activity multiplier is a starting point. ARC shows maintenance as a range for that reason. If you already know a calorie intake that held your weight for several weeks, enter that instead of the equation.
Weekend eating, liquid calories, and “bites” that never get logged are enough to erase a 10–15% deficit on paper.
The scale is noisy
Sodium, training, menstrual cycle, and gut content can move bodyweight more than a week of fat loss. A two-to-four-week average is more useful than any single morning.
If the average is flat and logging is honest, the next move is a small adjustment — not a jump to the most aggressive deficit the tool allows.
A real pattern
A 15% deficit on a 2,600 kcal maintenance estimate is about 2,200 kcal. If actual intake is 2,500 and steps dropped, there is no deficit. The fix is measurement and a truer maintenance number, not a 1,600 kcal crash.
Common mistake
Eating back every calorie a watch estimates from exercise, then calling the cut “broken.” Wearable calorie burn is not precise enough to treat as a bank account. See the companion guide on exercise calories.
Use the ARC tool
Run the numbers instead of guessing from the article alone.
How ARC treats this
- ARC’s calorie tool uses Mifflin-St Jeor and activity multipliers as estimates, and it will not print targets for under-18, pregnancy, breastfeeding, or eating-disorder concern.