Weight Plateau Calculator

Why the scale stalls

Most apparent plateaus have a mundane explanation. Glycogen stores fluctuate with carbohydrate intake and hold approximately 3 g of water per gram. Returning to a higher carbohydrate intake or simply varying daily intake can add 1–2 kg overnight with no change in fat. Similarly, new or intensified training causes muscle micro-trauma and glycogen supercompensation that can mask weeks of genuine fat loss.

True metabolic adaptation — a measurable reduction in resting metabolic rate beyond what body weight loss alone predicts — does occur after sustained periods in a calorie deficit. Research suggests this averages 100–300 kcal/day after several months of dieting, though individual variation is large. A diet break at maintenance calories for 1–2 weeks has evidence for partially restoring suppressed metabolic rate.

When to act — and when to wait

A meaningful plateau is a flat or rising 4-week average trend after accounting for the factors above. Single weeks — or even 2-week windows — are too noisy to conclude fat loss has stopped. Comparing rolling weekly averages rather than day-to-day weights is the most reliable approach for detecting true stalls.