Can you lose 10 pounds in 23 days?

It is certainly possible to lose 10 pounds in 23 days. It is important, though, to distinguish losing weight from losing body fat. If you are overweight or obese, losing 10 pounds of body fat is a good idea; however, it's a bad idea to lose lean muscle mass. If you do not exercise and eat properly, about half the weight you lose will be lean muscle mass and that is a bad idea. Since lean muscle mass is very much more metabolically active than fat, you want to preserve or increase your lean muscle mass. Losing weight too quickly, and by that losing your muscle mass, will leave you worse off. You will quickly regain the weight and probably more than you lost.