I don't think the liver "decides" whether to turn food energy into glycogen
or fat. It may be the liver that converts food energy to glycogen or fat. If
your glycogen stores are depleted in your muscles or your liver, then the
food energy goes to replenish them. But if they are not depleted, how can it
store any more glycogen there?
As i understand it, if you exercise and deplete your glycogen stores, then
when you eat the food energy will be preferentially used to replenish them.
If you have not been exercising and your glycogen stores are not depleted,
then if you eat a bid meal (especially one with a lot of carbs) the food
energy will be stored as fat.
Pat Fallon
pfallon@bigfoot.com