Why am I not losing weight?
If the math says you should be losing and the scale has not moved in three weeks, something in the inputs is wrong — and the most common causes are fixable. Work through this diagnostic, in order.
1. You are eating more than you think
Studies show people under-report intake by 20–40%. Bites, sips, cooking oil, “healthy” smoothies, and weekend meals are the usual suspects.
Test it: weigh every food in grams for one strict week. No eyeballing, no estimated restaurant portions. If your real intake is higher than your target, you found the leak.
2. You are trusting the wrong scale number
Daily weight swings 2–4 lb on water, sodium, carbohydrates, and glycogen. A single bad day can mask three weeks of real fat loss.
Test it: weigh daily, fasted, and run a seven-day moving average. Judge weeks, not days.
3. Your TDEE estimate is too high
Most people pick the wrong activity tier. “Moderate” should mean 3–5 genuine training days a week, not three casual walks.
Test it: take the 60-second activity quiz, then recalculate. If you were one tier too high, fixed — that is roughly 250 kcal/day.
4. Metabolic adaptation
During sustained dieting, NEAT quietly drops and BMR falls with mass. Your old TDEE stops matching your new body.
Test it: recalculate every 10–15 lb of weight change. If you have lost a lot, your current TDEE is meaningfully lower than your starting one.
5. You are not moving the way you were
Steps are the hidden lever. Losing 1,000 steps a day can erase a planned 200-kcal deficit.
Test it: check your daily step average. Hold it steady during the cut.
6. Not enough time yet
Deficits take 2–3 weeks to show on a seven-day average, longer around menstrual cycles or after travel.
Rule: no average change for 4 weeks with honest tracking → reduce daily calories by ~100–150 and retest.
Diagnostic flow, in order
- Weigh daily (fasted) and use a 7-day average for two more weeks.
- Audit intake with a food scale for one week.
- Re-take the activity quiz and recalculate TDEE.
- If still flat for 4 weeks: cut ~100–150 kcal/day and retest.
- If unexplained symptoms persist, see a physician. This is general information, not medical advice.
Frequently asked questions
I'm eating my TDEE minus 500 and not losing weight. Why?
Work through the diagnostic above. In practice, four causes cover almost every case: under-reported intake, water-weight noise, an overestimated activity level, or adaptation after recent weight change.
How long should I wait before changing calories?
Give the current target four weeks with a seven-day weight average. If there is no change, cut 100–150 kcal/day and test for two more weeks.
Should I fast for a few days to break a stall?
Extended fasting is not required and has drawbacks. A small, consistent deficit over 1–2 weeks achieves the same arithmetic without the muscle-loss and adherence risks.