Or broth of anything for that matter?
Let us say I use 1 pound of boneless chicken or chicken-with-bone for a broth. Then I only use the broth, discard the meat and/or bones. How many calories am I consuming?
According to this site, about 100 calories per cup.
But why just buy a chicken for the sake of making broth? If you're going to do that, just buy a brand-name low-sodium chicken broth instead and save some money. Low-sodium chicken broth only has about 15 calories per cup.
I make all my own chicken broth from leftover bones (no meat), and freeze it in 1 cup bags for use later. It is much better tasting than canned broth, and lower sodium to boot. I usually just enter it as canned, low sodium broth since I can't figure out how many calories it has, either. I have a hard time believing it has anything like 100 calories per cup as k leyv714 says, but who knows?
Besides the fact that homemade broth tastes better and generally has less sodium than store-bought, the price difference really isn't all that great. I can get two quarts of broth (plus the breast meat) from one whole (3 lb) chicken, and I can usually get a chicken for 5-8 bucks. Two quarts of canned/boxed broth will run me about $5, too. And as dkenworthy pointed out, you can make stock with just the bones (although I think the flavor is better with the meat).
If you separate the fat from the broth, I'd agree with ^ that 100 cals/cup seems really high. Looking at the description of the recipe from the provided link and the lower cal suggestions it makes, I think it might be talking about *soup* instead of broth/stock. Google "calories homemade chicken stock" and the values you'll see are more like 20-30 per cup.
That information makes no sense though - it says 2.9g fat, which is about 26 calories, 1g carbohydrates (4 calories), and 4.8g protein (19 calories). That's a total of 49 calories - not 100.
Plus, you can skim off virtually all of the fat if you're careful, so really, it shouldn't have 3g of fat per CUP - maybe 3g of fat in the entire pot. I have no idea about the protein, however.
Edit: This recipe has the following nutritional information, which sounds a lot more accurate to me.
Nutritional Analysis: One cup equals 33 calories, trace fat (trace saturated fat), 1 mg cholesterol, 89 mg sodium, 6 g carbohydrate, 1 g fiber, 2 g protein. Diabetic Exchanges: 1 vegetable.