Two more references about drinking urine;

Larry Dean Olsen - Outdoor Survival Skills, 1967 - pg. 33

"Drinking blood or urine only increases dehydration of the body. it is better to soak clothin in urine to cool the body by evaporation."

FM 21-76 US Army Survival Manual - 1994 pg 5-6''

"Caution: Do not substitute the fluids listed in figure 5-2 for water."

These fluids include:"urine - Contains harmful body wastes. is about 2 percent salt."

also FM21-76, pg3-2 "Do not use sea water or urine under any circumstances....if taken in sufficient quantity, will kill you."

Pretty consistent advice over many decades. I have never heard of any reputable source advocating drinking urine. Did Bear Grylls claim to have done such on one of his shows? Of course, he is hardly a reputable source...