While testing this i noticed a couple issues.
I do like the metabolism system its a great plugin but i have ran into some functionaly issues that prevent it from running properly.
The metabolism system stops function upon death and respawn. the only way to get it to work again is to reload the plugin but on occasion that causes instant death. When looking at the data file i noticed that the players who experienced instant death on reload had over 800 for Psych but the other 2 attributes are at 0. When the psych attribute is that high it does not reset and function properly after a reload but after several reloads it eventually starts working again. No matter what the metabolism plugin stops function properly when a player dies and respawns but only for that players, other players will not be affected unless they die as well and none of them will get the plugins functionality back unless i reload the plugin.
The other issue i found is that when the players character needs sleep and you are in a cold climate fire and heaters do not prevent damage from the cold.