Success in weight loss is not always what it seems to be. For some people, those who are able to lose 10 pounds in 9 days, are really really successful, but for other people who are able to lose 30 pounds in 3 month and able to keep the weight off permanently, are considered successful. So using diets for fast weight loss, may not be what you think it is.
Using diets for fast weight loss
I believe that your goal is to lose weight really fast and keep the weight off permanently. What is the point of losing a lot of weight really fast, if you are not able to maintain it, right? But the biggest problem that people have, is not that they are not able to lose weight, but that they are not able to maintain their weight. That is the biggest problem.
Unfortunately diets are not very good at losing weight successfully. You yourself have probably had success with a diet in the start, but as time goes on it gets much harder to lose weight. This always happens because weight loss is not always that straight forward.
For example if your maintenance level is 2000 calories and you cut your calories by 1000 calories, then in a week it would add up to 7000 calories, right? There is 3500 calories in a pound of fat, so in reality you would lose 2 pounds of fat in a week. This kind of a diet would really be successful, because it really is a fast weight loss.
But the BIG problem with losing weight that way, is that over thousands of years the human body has developed foolproof weight-regulating mechanism, that detects food shortages and in turn reduces the energy expenditure. All this is done to protect you from starvation. In other words - when you eat less, you burn less.
Secondly weight loss is not fat loss. For example if you are able to lose 20 pounds in 3 weeks, then you can be sure, that maybe 50-60% of the weight you have lost, is actually fat. Yes, you can certainly lose weight fast with diets, but it is not very smart to do this. Using diets for fast weight loss will never give you permanent results.