Perhaps you saw it coming for quite a while, and knew it would get to this point. Or, maybe you looked in the mirror one day and all of a sudden realized just how much weight you have put on over the years. Chances are good that the second scenario is more likely. Most of us don’t want to be overweight. And while we may have a few clues as to how we got here, it still comes as somewhat of a shock. Either way, you have finally made the decision to shed those extra pounds once and for all, and you want to lose weight fast.

Hold on! That is an admirable goal, but you need to step back for a moment and put things into perspective. To put it another way, you need to be realistic and specific. How much weight you want to lose and how quickly will play a bog role in which diet and exercise program you choose.

You still have to be realistic though. If you want to lose 20 pounds in 2 weeks, then you’re not going to have much luck. Not only that, but any diet that makes such promises is most likely lying at best, or bad for your health at worst. It simply isn’t safe to lose that much weight, except for a few rare exceptions, and only if you are doing so under the guidance of a qualified medical professional.

Most experts agree that losing 1 or 2 pounds per week is safe and effective. However, you may be able to bump that up to 5 pounds in the first week in some cases. For most people, 1 to 2 pounds is ideal. It’s not only relatively easy, but you will be more likely to stay on such a diet. If you have a choice between losing 20 pounds over two months, only to regain it; or losing 1 pound per week over the course of 6 months, but keeping it off forever, which one would you choose.

The good news is that you don’t really have to choose. You can still lose the 20 pounds, but if you take the right approach, you will be able to keep it off. It’s all about a simple formula: 3,500 calories is equivalent to 1 pound of body weight. That means if you take in 500 calories less per day for a week, you will lose 1 pound. Or, if you burn off an extra 500 calories per day, you will lose a pound.

So, here’s the real “secret” to lose weight fast: do both! Take in 500 calories less and burn off an extra 500 calories. That’s 1,000 calories per day in your favor. That’s a loss of 2 pounds per week, or just over 100 pounds in a year’s time. And the best part it is that it won’t be nearly as hard as if you were depriving yourself, and that means you will be able to keep the weight off for good.