Because eating nothing is not sustainable for more than a few weeks. If you have that slow of a metabolism then you should either build more lean mass and get

Because eating nothing is not sustainable for more than a few weeks. If you have that slow of a metabolism then you should either build more lean mass and get more active, which drives up the metabolism, or eat less. One way to eat less without feeling hungry is to eat bulkier food, more fibre, and lower GI foods. Since I started eating pure rye bread I'm much less hungry.