Low Carbamide/creatinine

[Pet Peeve]

I did a lot of blood tests some months ago. Everything was within reference except carbamide (urea) and creatinine:

Carbamide 2.1 mmol/L (3.2 - 8.1)
Creatinine 59 µmol/L (60 - 105)

I find info on too high values but very little info on too low values. Liver problems? Can't break down proteins sufficiently? Should I supplement urea and creatine?

 

[DesertRat]

I'd like to know too. My creatinine is always low.

 

[Pet Peeve]

I'd like to know too. My creatinine is always low.

I'm skinny with little muscle mass, but I wonder if this is the cause or the result of these low values. How is your constitution?