I'm with the consensus on here, definitely drink more... well I think I do anyway. Whereas before I'd have 2 cans of gassy inferior bitter, then feel bloated and not want anymore, now I'll probably revisit the keg a number of times each and every night. Saying that though, each pour (due to my kegs seeming to be incredibly lively) is probably only about 1/3 - 1/2 a pint once it's settled down!
As for more fattening, ABV plus volume of beer consumed is your enemy here. Alcohol isn't in an easily useable form for your body to use in respiration, so it will do what it can with any sugars in the beer and the alcohol it'll store for later use. In times of starvation, your body will turn fat reserves into sugars, and alcohol has got simple sugar molecules as part of the chain. The higher the ABV and the greater the quantity of it you drink, the more your body will become adept at storing the calories for future use. The same reasoning is why crash diets never work, your body spends the time whilst you're on the crash diet honing its ability to make use of every single calorie it can. When you reach the weight you want and then go back to a normal diet, all of a sudden there are more calories than the body needs and as it so honed at retrieving every last bit of energy from the food, the extra is put down as fat in case there is another starvation episode.
A lot of the above is being dragged from my degree taken over 15 years ago, so apologies if parts are vague or not quite remembered correctly!
