Temporary weight gain after consuming alcohol is a common phenomenon. This weight gain is usually due to water retention caused by the diuretic effect of alcohol, which makes the body retain water and leads to temporary bloating and swelling. However, this temporary weight gain is not the same as actual fat gain, and it usually goes away within a few days. Heavy drinking over time, on the other hand, may lead to actual weight gain, as it may activate hormones that signal appetite, hunger, and stress. This may result in overeating and a higher calorie intake, which can lead to weight gain over time. Additionally, alcohol itself is high in calories, and regular consumption of alcohol can contribute to weight gain in the long term.