The scale is the wrong signal. Watch your deficit
The scale jumps 1-2 kg overnight from water, salt and stored carbs you don't control. The number you do control is your daily calorie deficit. Watch that instead, and weigh only for the trend.
You step on the scale. It is 1 kg up from yesterday. Your heart sinks. You ate so well yesterday. Did it all fail? No. The scale is shouting at you about water, not fat. There is a quieter, truer number — your daily calorie deficit. Burnie shows it to you every day, free. That is the number to watch.
What the scale measures is mostly water
Your weight can change 0.5 to 2 kg in a single day. Almost none of it is fat. To gain 1 kg of real fat you need about 7700 extra kcal — impossible in one night. The jump is water. Salt holds water. Carbs store water in your muscles as glycogen. Each gram of glycogen binds about 3 grams of water. So a big dal-roti dinner can lift the scale 1 kg by morning. One study tracked one man's weight for almost 30 years. Day to day it swung with a standard deviation of 0.53% — about 0.4 kg in a 75 kg person — and almost all of that was water.
The daily scale tells me if my diet is working
mostly falsemostly false
The daily scale mostly tells you about water, salt and glycogen, not fat. So it swings even when your diet is perfect. Researchers listened to people weigh themselves daily. Disappointing numbers made some want to give up. One person said she had no idea if the swings were water, fat or muscle. That confusion is the trap. A noisy number you cannot read is the wrong signal to steer by.
Scale vs deficit: which number you control
Watch the deficit, not the day
The bottom line
Your diet's true score is the daily calorie deficit, not the scale. The daily scale is mostly water noise you can't control. Watch the deficit, weigh for the weekly trend, and trust the math. That is the Burnie way.