A person who is starving is losing?
fat only,glycogen only,glycogen and fat only, or glycogen protein and fat?
Starvation is the breakdown of all three macronutrients. The last one, baby. The last one.
Nothing... when you don't eat enough, your body goes into a 'preservation' mode and you actually burn FEWER calories than what you do if you eat on a regular basis. Your body starts to use less to keep you alive longer off of your stored fat.