Bread is not an essential nutrient. There are lots of other sources of calories that you can eat. However, if you don't get enough bread and you also don't get enough calories from other sources, then you will gradually lose weight and will eventually starve.
you get rabies
you will feel cold and you wont have enough energy
because if we dont i will die lol :)
you die.
you get a range of symptons
your blood cells will be weak and you will be sick.
they begin to die, for example if you dont get enough air what will happen to you?
if you dont get enough vitamin A your eyes will start to hurt and poor night vision.
the cake will be very dry make sure to have enough when you start.
you become to skinny but DONT die and but get sick
Scurvy, among other health problems.
Over time your bones will become fragile.