Basically, I started a new game (my fourth) and for some reason, now when I go to sleep for 8 hours, I die from thirst and starvation, even when they are both at 0 when I go to sleep.

I don't think this is mod related, but if it is, here's my load order:

FalloutNV.esm
CaravanPack.esm
UsableCigarettes.esp
Leather Trench Coat NV v1.0.esp
Holster.esp
xatmosSkillPerks.esp
PortableCampsite.esp
UnlimitedCompanions.esp
LFox Invisible Armored Vests.esp
NewVegasRestorationV1.esp
IHATECAZADORES.esp
FreeplayafterMQNVv1_6.esp
Better Casinos.esp
NV Interiors - West Vegas Fringe.esp
Facepuncher.esp
UrgeWasterScarf.esp
Lone Wanderer Armor NV.esp
Lucky38SuiteRemodel.esp
NCR Ranger Outcast Armor.esp
z_Fiends_2.esp
The Clues.esp
Power Armour is Powered.esp
CONELRAD 640-1240.esp
UrgeWasterScarf (2).esp
behemoths.esp
Sunglasses Shipment.esp
Nevada Skies.esp

Total active plugins: 27
Total plugins: 33

Happens if you set Timescale too low. Sleeping with a timescale of one is deadly because the game counts the water/food needs at thirty times the correct rate.

http://www.newvegasnexus.com/downloads/file.php?id=34718 has protection against that.

EXCELLENT! Thank you so much for posting precisely what I needed!