My 12 year old dog stopped eating about 3 days ago. When I got o feed him he still gets really excited like normal but then doesn't touch his food. I feed him dry biscuits in the morning and dog roll at night and he hasn't touched anything. Otherwise he seems normal and nothing else has changed. Should I be worried or will he eat on his own when he gets hungry enough?

I think a 12 year old that suddenly quits eating needs to see a vet. This could be one of a number of things, some of which are treatable. With a younger dog, I would refer you to a web site on maintaining proper weight and suggest waiting him out.

Labman is absolutely correct. A 12 year old dog that suddenly stops eating needs to see the vet ASAP. There are some very serious conditions that could be causing this issue. Hopefully it is a minor problem, but with a 12 year old (equivalent to 61 human years old) it should not be ignored.

2 red flags
"My 12 year old dog "
"stopped eating about 3 days ago"
Before you race down to his vet, look around for anything unusual, missing children, damaged plants, Headless armymen, dead bugs, secret santa (neighbor supplying anything the dog will swallow) Hole in the back of the 60lb feed bag. Don't laugh aside from the missing children, others I listed have been the cause of suspected anarexia. Arm yourself with time lines events and different behavior to help your vet. I have a feeling If we ask your dog these things, its mums the word. It won't hurt to see his blood chemistry anyway according to his age. Let us know what the results are after the visit. Good Luck!

How long do they live if they stop eating?
11 yr old Dog F. Lab/beagle mix

How long will your dog live if it stops eating? Lab/beagle mix 11years old F.

Not long.
How long has she not been eating, and why haven't you taken her to the vet yet?