This article goes through 3 common reasons why you're not losing weight. 1. You might be losing weight without realizing it. If you're basing your progress on the scale, don't freak out just yet. The scale does not take into account your body fat percentage. Your body weight will fluctuate daily based on foods, hormones and water retention. It is also possible that if you're weight lifting (which I highly recommend doing), you may be gaining muscle at the same time as losing