When in a mine cart, you don't loose hunger. If you have at least one hunger left and you sit in the mine cart, you stay alive. However, if you have no hunger left you will still take damage when in the mine cart.
MC-84750
When in a minecart, You don't loose hunger.
Resolved
Duplicate
0
Sarah Turner
(Unassigned)
Unconfirmed
Minecraft 15w31c
Retrieved
Thank you for your report.
However, your ticket has been resolved as a duplicate.
This issue has been linked to the original bugreport: MC-14640. You can find or add further information on that report.
Please search before reporting any bugs, as it's likely that one exists already.