What brand are you using?  I've noticed that if my cats can't smell
it they won't eat it.  So i've stopped using certain brands as a
result.  
--------------------------------------------
"It took us 15 years to McGyver this thing."
-------------------------Carter on Stargate

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my e-mail address.

If i was in your position i'd get my cat checked out at the vet's just to
make sure
it's nothing untoward.

I had this happen with my 15 year old last November. If it were me, I would
take this cat to the vet in the next couple of days to check out any health
concerns there may be. In the interim, I would check if she is drinking a
normal amount of water.

Good luck!

Rolf.

Taking her to the vet is always the best choice, but here is my story :)

My brother had a female black and white named Suzie Q.  About the time she
turned 13, she started loosing weight.  We tried different diets, foods, and
even took her to the vet.  There was nothing wrong with her.  She ate like a
pig and just kept loosing.  She even caught her own food on top of what we
were feeding her.  By the time she was 20, there was hardly anything left of
her, but she would still chase the dogs (no matter how big) out of the yard,
and was as feisty as ever.  Some animals gain as they get older (like my
mom's cocker spaniel), some loose it all like Suzie Q.

Hope this helps, Vet is your best choice though.

DD and Tigger

could be a bad tooth or something that makes eating painful..or some
other mouth problem

Have her checked out