Why did my weight loss stop, and how do I break a plateau?

Weight loss slows because a smaller body burns fewer calories, and your body also adapts by spending a bit less energy, so the deficit that worked at first shrinks. Check your weekly average weight over three weeks, tighten your logging, then cut 100 to 200 calories a day or add some activity. A planned break at maintenance can also help you keep going.

1. Confirm it's a plateau. Compare weekly average weights over at least three weeks. Daily weight swings with water and food.
2. Tighten your logging. Check oils, sauces, drinks and weekends, where calories are easiest to miss.
3. Recalculate your target. You weigh less now, so your maintenance is lower. Recheck it.
4. Make one change. Cut 100 to 200 calories a day, or add a daily walk. Then wait two to three weeks.
5. Consider a break. If you've been dieting for months, a week or two at maintenance can make the next phase easier.

Why it happens

Two things shrink your deficit over time. First, a lighter body burns fewer calories just to exist and move. Second, research on dieting athletes describes “metabolic adaptation”: your body spends a little less energy than predicted from the weight you lost. A 2011 analysis showed weight loss follows a curve, not a straight line, for these reasons.

Common hidden causes

• Logging drift: portions grow and small extras stop being logged.
• Weekends: two loose days can cancel five careful ones.
• Water weight: salt, carbs, stress or a hard workout can hide fat loss on the scale for a week or more.
• Moving less: people often move less without noticing when they eat less.

If you’ve stopped losing weight for months despite careful changes, or you feel unwell, talk to a doctor.