Is my plateau real or water weight?

If the scale has been flat for less than two or three weeks, it’s most likely water hiding fat loss. If your weekly average has been flat for a month while you log everything you eat, the plateau is real, and it’s time to adjust.

What hides fat loss

• Carbs. Your body stores carbs in muscle with at least 3 grams of water per gram, so a carb-heavy weekend can show up as a gain that isn’t fat.
• Your cycle. In a year-long study of 62 women, fluid retention peaked on the first day of the period.

Daily weigh-ins are like daily stock prices. They jump around, so you judge the trend line.

What makes a plateau real

• Weekends. In a year-long trial of 48 adults aged 50 to 60, the people cutting calories lost weight on weekdays and stopped losing on weekends.
• Logging drift. In a 1992 study, 10 people who said they couldn’t lose weight on very few calories turned out to eat 47% more than they recorded. Their metabolism was normal.
• A smaller you. As you lose weight you burn less, so the same diet makes a smaller gap. See why weight loss slows down.

What to do

1. Weigh every morning and use the weekly average.
2. Compare this week’s average with the one from three or four weeks ago.
3. If it’s truly flat for a month, check your log, weekends included. Then cut about 100 to 150 calories a day or add a daily walk, and give it another three weeks.