Scales don't lie, but they aren't telling the whole truth.
Scales will tell you your TOTAL weight.
This includes the weight of your blood, bones, muscles, water and organ - all of which is NOT fat.
Now during the course of a day many substances including food in the body, excretion (fecal, urine) and even water amounts AND muscle mass can be lost or gained.
Fat can also be lost or gained, but as you can tell now, your regular scale will not measure JUST fatloss.

You CAN get a body lean/fat mass % ratio scale. Here's one of many brands.

http://tanitascale.com/home_scales/tbf531.html

It does tell you if your BODY FAT % alone has changed during the day or from the last time you wieghed. They cost a bit more, but if you REALLY want to know if that WEIGHT your regular scale told you you lost or gained was FAT or if it was urine or sweat or muscle or fecal matter or food intake.

The regular scale DOES tell you your TOTAL weight HONESTLY.
It just doesn't tell you WHICH of you weighs less and WHY.

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