A common thing I see here is you shouldn't try to lose too much weight too quickly, or you will lose muscle. Some people recommend 0.5 pounds per week, some people recommend 1 pound, etc. I'm not here to debate what the best amount to lose is.
Let's ASSUME that losing 1 pound a week is ideal, okay? Now, let's also keep things simple and say that my maintenance is exactly 3000 cals per day, so I need to eat 2500 calories per day (500 deficit) to lose my 1 pound per week (500*7 = 3500 calories = 1 pound of fat).
Okay, so my question is, is there a difference between eating 2500 calories every day and eating let's say 2000 calories for 6 days and 5500 calories on day 7? Either way that's 17500 calories per week, which is 3500 below my maintenance of 21000.
The reason I'm asking this is because I eat about 1700 calories on the days when I stick to my diet, and I justify a cheat meal once or twice a week by saying I don't want to lose too much too fast. I want to make sure I'm not hindering my progress.
Here is my worst-case scenario that scares me. For those 6 days, I'm eating too few calories, and thus burning muscle along with the fat. Then, on the 7th day when I cheat, I'm gaining fat because I'm eating way over maintenance. So, even though I may have lost a pound for the week (cals in vs. cals out), I have actually lost 2 pounds of muscle and gained 1 pound of fat.