Everyone has a reasonable idea of how much weight to lose on a regular basis. My only problem with the responses on this thread is simple, none of them take into consideration the person who is starting a weight loss program. I am going to assume that you are discussing how much weight loss in a month is acceptable for people in the personal trainer program. The correct answer to this question depends on the person who is starting the program. If someone joins the personal trainer program and already has six pack abs and body fat percentage of 5%, you can't expect them to lose very much over the course of a month. If, however, the person is 5'4" tall and weighs 290 pounds, it wouldn't be uncommon or even unacceptable for a person to lose more than 15 pounds in the first month alone. It depends on the person.