When fewer calories are consumed, the body compensates by reducing many of the hormones involved with thyroid function/metabolic rate (T3/T4, leptin, etc.) and increasing production of an enzyme called lipoprotein lipase, which conserves food energy by storing calories as fat. In simple terms, when you restrict calories too low your body doesn't necessarily know when your next meal is coming, so it'll take what little calories it is getting and store them as fat for later use.


starting too low ill have short life and will stall quickly
then sometimes now matter how low you reduce or how much extra cardio you do the stubborn fat wont shift as metabolic rate slows and will end up burning the thing you don't want to that's muscle