Cutting salt is a method to lose water weight. In reverse, eating salt will cause water retention (water weight gain). This is why you can sometimes go out, eat something salty (say tortilla chips with salt at a Mexican restaurant, mmmmm ;-) wake up the next morning, and your scale says you have gained like 4 pounds! You'll think to yourself, there's NO way I even ate four pounds of food! But all that's happening is your body is holding on to more water.
Anyways, the point is that salt intake / hydration level manipulation is great for a quick drop for a weigh in (as wrestlers and boxers do) or to create more definition for a photo shoot (de-hydrating will make your muscle definition pop), but long term isn't sustainable. For the brief period of time you dehydrate your body your energy levels will be low, and if you were to do it for a prolonged time, your body chemistry would freak out and you would most likely binge on something salty (likely high in calories as well) to get back into balance.
Bottom line, cutting salt (or all of the other methods for dehydrating, i.e. sweat suits, sauna's, etc.) should not be a part of any long term strategy.
:-)
Happy Fitness!
- Eric