Yes it's nasty. No raw carrots won't stop the behaviour. My two 9 month old malamute pups eat raw carrots all the time and the male loves to eat poop!
It's hit and miss with him, and is not diet or health related. A friend who is a trainer assures me it's boredom, and she may be right.
I also heard that pineapple may help, and I tried some canned but it didn't help. I did read that it had to be fresh afterwards. Haven't bothered though.
I agree that at 11 a senior workup is in order to rule everything out as it is a sudden change in behaviour, but also consider the boredom thing.