What is the lowest calorie cat food available?

http://www.healthyfoodforpets.com/cat-adult.html

What about this?

That's too funny-- I just ordered a sample pack from them earlier today! Thanks!

I don't know about low calorie, but the best by far is Nutro. Most cat
food has fillers like corn, wheat and by products. Nutro doesn't have
any of that, it's much healthier. And since it doesn't have much
fillers, the cat eats less and the amount of waste is smaller as they
can't digest wheat products, it just goes through them. Hence when
there's wheat etc the cat needs to eat more to fill full etc. I
started my cat on Nutro a year ago, she's happier, healthier, coat
looks much better, she's easier to clean up after, and she's lost
weight too. I'd give it a try. :)

Thanks very much for your input. I will see if Nutro has some sort of
light formula... my adult cats were a couple of pounds overweight to
begin with, but when I got a new kitten, they started seriously
bingeing. They're really big now, and I'm worried!

I'm a volunteer with an animal adoption organization, and two of the
veterinarians who work with us have recommended Natural Balance
Reduced Calorie Formula for the hefty kitties who need to slim down.

http://www.naturalbalanceinc.com/catformulas/RedCalCat.html