Craving Mustard

I am 6 months out and have been craving mustard and even squeeze it right into my mouth and eat it.  I just had lab work and all my labs and vitmens and iron are good.. so I really would like to know why we crave pickles, pickle juice and vinegar..    BRING ON THE MUSTARD.   By the way I am still on only protien and have lost 168 pounds so far. 

Ooops 2 years out!