You set a calorie target, you’ve been hitting it, and the scale is exactly where it was two weeks ago. Maybe it even went up. Before you cut more food or decide your metabolism is broken, go through the list below in order. The first reasons are the most common; the last ones are the rarest.
This article is general information, not medical advice. If you have a health condition, are pregnant, or take medication that affects weight, talk to your doctor before changing how you eat.
First, is it really a stall?
Body weight moves up and down by a kilogram or more from one day to the next, mostly because of water and food still in your gut. A salty dinner, a hard workout or a bad night of sleep can all push tomorrow’s number up. One reading tells you very little.
What to do instead:
- Weigh yourself at the same time each day: after the bathroom, before eating or drinking, on the same scale.
- Write the number down and look at the weekly average, not the daily number.
- Give a change at least two to four weeks before deciding it isn’t working. Fat loss is slow compared with water swings, so it often shows up in steps rather than a smooth line.
If your weekly average has gone down, even slightly, you are not stalled. If it has been flat or rising for three to four weeks while you’ve been consistent, keep reading.
1. You’re eating more than your log shows
This is the most likely reason, and it isn’t about willpower. Logging is hard for everyone. In a Dutch study of 269 adults, 3-day food records came in at about 277 kcal a day below the energy they actually needed to keep a stable weight, and women under-reported more than men (de Vries et al., 1994). A group of obesity researchers later wrote that systematic under-reporting has been found in almost every study that checked self-reported intake against measured energy use (Schoeller et al., 2013).
A gap of a few hundred calories a day is enough to wipe out a moderate deficit. It usually hides in three places.
Portions you eyeball
“A bowl of pasta”, “a handful of nuts” and “a medium banana” can be very different from the portion in your app’s database. Eyeballing is fine long-term (here’s how to count calories without a food scale), but if you’re stuck, weigh or measure your usual foods for a week. You’ll quickly see which portions you guess well and which ones you don’t.
Oil, sauces and drinks
These are the calories people forget most often, because they don’t look like food. Olive oil has about 119 kcal per tablespoon (USDA FoodData Central), and a tablespoon disappears quickly in a frying pan or over a salad. Dressings, mayonnaise, butter on toast, milk and syrup in coffee, juice, smoothies and alcohol all count too. Our chart of hidden calories in oil and sauces lists the numbers per spoon.
If you log by photo, this matters even more: oil and butter are mostly invisible in a picture of a plate. In Munoo, the photo result is an estimate you can edit before saving, so add the oil yourself. Typing or saying “1 tbsp olive oil” takes a few seconds.
Weekends and small bites
A careful Monday-to-Friday can be undone by two relaxed days. Tastes while cooking, the kids’ leftovers, a biscuit at work and “just a bit” of dessert are easy to skip in a log. None of these is a problem to eat. They just need to be written down if you want your numbers to match reality.
2. Your exercise burn is lower than the app says
Fitness trackers are decent at counting steps and heart rate. They are much worse at calories. When researchers at Stanford tested seven popular wrist devices against lab measurements, even the best one was off by about 27% on energy expenditure, and the worst by more than 90% (Shcherbina et al., 2017).
If your app adds exercise calories back to your daily budget and you eat them, you may be eating your whole deficit. For the next two weeks, don’t eat back exercise calories. Keep exercising for your health and mood, but treat the burn figure as a rough guide, not a budget.
3. Your target is from an older, heavier you
A smaller body uses less energy. As you lose weight, your maintenance calories drop, and the target that gave you a deficit three months ago may now be close to maintenance. Research from the US National Institutes of Health also shows that the body’s response to eating less is slower than old rules like “3,500 kcal = 1 lb” suggest, because energy use adapts over time (Hall et al., 2011). The NIH’s free Body Weight Planner is based on this model.
Recalculate your target with your current weight. Our calorie calculator does it in a minute, and the calorie deficit guide explains how big a deficit makes sense.
4. Water is hiding fat loss
Fat loss and weight loss are not the same thing on a given day. Water can mask fat loss for a week or two, sometimes longer. Common reasons:
- Salt. A salty meal makes your body hold extra water for a day or two.
- New or harder training. Muscles hold water while they repair.
- More carbohydrates than usual. Stored carbohydrate is kept with water.
- Stress and poor sleep. Both can affect fluid balance and appetite.
This is why the weekly average matters more than any single morning.
5. Your cycle is shifting the scale
If you have periods, your weight can move in a pattern across the month. In a year-long study of 62 women, self-reported fluid retention rose around ovulation and was highest on the first day of the period (White et al., 2011). Many people also notice more appetite before their period.
What helps:
- Compare your weight with the same point of your previous cycle, not with last week.
- Expect the scale to look worse around your period and better a few days after.
- Log the extra snacks honestly. They’re normal and they fit into a week.
6. Sleep and stress are raising your appetite
Short sleep changes appetite hormones. In a small lab study, two nights of restricted sleep lowered leptin, raised ghrelin and increased hunger, especially for calorie-dense foods (Spiegel et al., 2004). In real life, that shows up as bigger portions and more snacking, which brings you back to reason 1.
You don’t need perfect sleep to lose weight. But if your log goes off track on tired days, that’s useful to know. Plan a filling, high-protein meal for those days instead of trying harder to resist.
7. A medical reason: when to see a doctor
Some conditions and medicines make weight loss harder. An underactive thyroid (hypothyroidism) lists weight gain among its common symptoms, though the US National Institute of Diabetes and Digestive and Kidney Diseases notes that tiredness and weight gain are common and don’t by themselves mean you have a thyroid problem (NIDDK). PCOS and some medicines can also affect weight and appetite.
See a doctor if:
- your log is careful and your weekly average hasn’t moved for two months or more;
- you have other symptoms such as unusual tiredness, feeling cold, hair loss, or irregular or very heavy periods;
- you started a new medicine around the time the scale stopped moving.
Don’t stop or change any medicine on your own.
A 14-day audit you can start today
The goal is to find out which reason applies to you before changing anything. For two weeks:
- Fix your weigh-in. Same time, after the bathroom, before eating, same scale.
- Weigh daily, compare weekly. Only compare week 2’s average with week 1’s.
- Log everything. Oil, sauces, drinks, tastes and bites included. Speed helps here: in Munoo you can log by photo, barcode, a photo of the nutrition label, or a short text or voice note, so small items don’t get skipped. Manual logging has no daily limit on the free plan.
- Measure what you usually eyeball, at least for the first week.
- Don’t eat back exercise calories.
- Recalculate your target with your current weight.
- Decide after 14 days. If the average dropped, keep going. If your log shows more than your target, you’ve found the gap. If everything looks right and nothing has moved for weeks, lower your target by 100–200 kcal or talk to a doctor.
Looking at your weight trend instead of daily numbers makes this much less stressful. One heavy morning stops feeling like a failure.
What not to do
- Don’t slash calories. Cutting hard on top of a logging error usually leads to more hunger and more unlogged eating. NICE suggests aiming for no more than 0.5 to 1 kg a week.
- Don’t try to “earn” food with exercise or “burn off” a big meal. It turns exercise into punishment and makes the numbers less reliable.
- Don’t change five things at once. Change one thing, then wait two weeks.
- Don’t judge one weigh-in. Look at the trend.
If food, eating or your body feels hard to cope with, or you find yourself restricting more and more, please talk to a doctor or an eating disorder support line. In the UK that’s Beat; in the US, the National Alliance for Eating Disorders.
The short version
A deficit that “stopped working” is usually a deficit that’s smaller than it looks. Check your log first, especially oil, drinks and weekends. Then check your exercise numbers and your target. Give water and your cycle two to four weeks to settle, and see a doctor if careful tracking still shows nothing after a couple of months.