Brown tongue

MamaMoosicorn have you tried googling this? I personally have never heard of this happening to someone on ketogenic but I suppose a little research you should do! Scary ! I found this though on first search. 

“A black or brown tongue typically is due to theovergrowth of bacteria that normally are present on the tongue. This, too, can be caused by thekilling of some bacteria with antibiotics so other bacteria overgrow. But the most common cause of discoloration of the tongue is the overgrowth of a fungus.Aug 8, 2004

Did you take Pepto Bismol for an upset stomach or something? That can cause your toung to turn brown or black overnight but after brushing it typically goes away within the same day.

Could also be heavy metals.