Weight is not equal the Fat because the scale spikes does not mean you gained fat overnight.
Weight is so many things aside from fat. Weight is the food you have in your stomach. Weight is the bottle of water you drank. Weight is you bones ( related to density). Weight is your muscles. Weight is your body holding onto water because you had a salty meal. Weight is your body holding onto water because you are physically, mentally and emotionally stressed out.
Weight is more than fat and many time you will step on the scale and see it jump a pound or two or may be three from the day before. It is not fat. It is physiologically impossible to gain that much fat overnight. It is weight. That is it.
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