How many gills in a pennyweight?

More than a year ago, I went on the Atkins diet, because I had topped 200 pounds — and there is no one anywhere who thinks that this is an appropriate weight for someone who’s 5’8″. I ended up losing about 25 pounds after about 9 months, which is pretty good. Then, I stopped the diet because it was my busy time of the year and I just didn’t have time to deal with it.
Well, it’s taken me a bit longer than a year to put all that weight back on.
Now, as we all know — despite what Dr. Greg Cyaumon, Ph.D and other quacks on late night commercials say — it’s not about a nasty stress hormone or something that can be dealt with by a pill. It’s about poor eating habits and little exercise. I’ve got those in spades.
The major problem, eating-wise, is that I just don’t think about what I am eating, and I don’t cook 99% of the time because I live alone and cooking is a pain.
Nevertheless, I’m trying a new tack. I’m trying to not worry about such things as carbs, etc., and just concentrate on calories. Of course, this has it’s problems as well.
Yesterday I managed to squeak by on 1,074 calories — quite a change from my normal intake, which is probably in the range of 3,000 or so, mostly junk food. In that 1,074, I managed to sneak in 29 jellybeans for 140 calories.
So far today, I made scrambled eggs, which came in at 183 calories. Now I’m getting hungry for lunch and figured I’d have soup — but now we reach the real problem: figuring out how many calories are actually in something.
I have 4 cans of soup here. The label of each one has a different definition of what one cup is: 240mL, 237g, 245g, 250g. The conversion utility on my Mac says that a cup is equal to 227g.
I wonder what NIST would think of this? They say that 8 ounces (1 cup) equals 232mL. So how does that convert to grams? Oy.
I think the major stumbling block to losing weight is the math.