The latest episode of Inside Star Citizen explains how Cloud Imperium plan to implement survival mechanics, with senior FPS systems designer Jonny Jacevicius saying that, while “Star Citizen’s not a survival game in the traditional sense,” it will have an “actor status system” to cover eating, drinking, and maintaining temperature.
Both hypothermia and hyperthermia are potential outcomes of failing to wear the right suit when you explore a planet, with vision effects and then eventual death if you don’t do anything to rectify the situation. There will be buffs and debuffs from food and drink, with the example given of a chocolate bar that might add stamina regeneration, while medicine can provide a small amount of health regeneration.
The video goes on to discuss the way Cloud Imperium Games’ quarterly go/no go meetings work, so you can probably skip the rest of it unless you’re a really dedicated Citizen.