Beer contains calories which add to your daily caloric intake. If you are drinking 500 extra calories in beer a day, you will add 500 extra calories to your daily intake which can increase your weight because your body is taking in excess of what it requires to operate on a daily basis. The same would go if you ate 500 extra calories a day. It's all based on the numbers.
I dunno' when I drink 2 or 3 beers a night at home where I'm not eating fatty bar food I still gain weight.
When I'm trying to loose weight I have to limit myself to the occasional beer.Weight gain over a year
Even though beer itself contains some calories, there is no fat in it, only carbs. And 500 calories of beer would be something like 40 ounces of the most caloric beer. So beer itself is not the primary reason for weight gain, as a glass of any sugared carbonated drink (like Coke) contains way more calories than the same amount of beer. The problem is not so much in beer itself, but in the high-fat junk that people often eat along with the beer (or any alcohol) - pizzas, potato chips, subs, etc. So the influence of beer is more indirect than direct. You should watch what else goes with it.How can I just gain weight?