Mass of our body

Mass is the amount of matter present in our body rite and mass doesn’t change with place, it’s constant.

The thing which we actually measure in the weighing machine at home, dispensaries etc is

our mass actually than how the hell does it change?

What you measure with a "weighing" machine is your weight... W=mg. Weight is a force for your mass, m=W/g.. For example, if your weight is 98 N (it is scientifically wrong to express weight in kg; unit of weight is Newton or kg m s^-2) your mass is 10 kg.

Weight machine tells the reaction of the force have applied on it. Its reading might be different at different places on earth or even in space or can change according to your reference frame. Go to the escalator and check your weight while it is going upward and downward. It might be different.

I don't think you got any change from inside of you but all about the frame. So mass is constant until and unless you hold your breath and do not eat anything.

Mass is M= m/root of [1 - c/v(square ) ]

where m=rest mass [is const. everywhere]

c=velocity of light

v=velocity of particle

So if particle moving with velocity of light, is mass have to be zero.

The weighing machine measures canonical weight. The variability is transferred to the mass term and the units adjusted accordingly such that gravitational acceleration is set to unity (G=1).

Your weight changes on the machine if you store more fat or reduce it, by adding muscle bulk or reducing it - it’s biological.