How fast should you lose weight? A safe, sustainable pace is roughly 0.5–1% of your bodyweight per week. Go faster and more of what you lose tends to be muscle and water rather than fat — and the fatigue, hunger and rebound that follow make it hard to keep off. Patience, not speed, is what protects the body underneath.
When the deficit is gentle, the body has time to draw mostly on fat stores. When it’s aggressive, it starts breaking down muscle for fuel too, and that’s the opposite of what most people want. For someone around 80 kg, 0.5–1% a week is roughly 0.4–0.8 kg — a number that feels slow on the scale but tends to come off as fat and stay off.
Eating a little less than you burn is what drives fat loss, but bigger is not better. A modest deficit — on the order of 300–500 kcal a day for many people — is usually enough to hit a safe weekly rate while leaving you enough energy to train and recover. Very low-calorie crash diets tend to strip muscle, tank your mood and end in a rebound once normal eating resumes.
Two levers tell your body to keep its muscle while fat comes off: eating enough protein and training that muscle. Adequate daily protein and some form of resistance work — bodyweight, bands or weights, a few times a week — give muscle a reason to stay. Without them, a deficit alone will happily burn lean tissue alongside fat.
Skimp on sleep during a diet and the same weight loss skews toward muscle rather than fat, while hunger hormones push you to eat more. Studies of dieters who slept short have seen a larger share of lost weight come from lean mass. Treat seven-plus solid hours as part of the plan, not an optional extra — it’s doing real work in the background.
When you set a weight goal, Vitra gives you an honest date range instead of a fantasy deadline, plus a safe-pace band of 0.5–1% per week and a rough daily calorie target to match it. Then it tracks a smoothed weight trend, so you see real progress through the day-to-day noise of water and food — all computed locally on your own machine, from your own numbers.
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