Putting your body in starvation mode makes it think it needs to store fat when it gets the chance, so as soon as you start eating again, that's what it does. It changes your metabolism and it's hard to get it back to normal. Not to mention, starving yourself is hazardous to your health. Food is required for things like basic organ function. You can honestly lose more weight more comfortably and keep it off for longer by just eating right. Check out a book called the Fast Metabolism Diet, it explains everything and I have seen it work for many people.
Blood vessels (veh-suls): The system of flexible tubes—arteries, capillaries and veins—that carries blood through the body. Oxygen and nutrients are delivered by arteries to tiny, thin-walled capillaries that feed them to cells and pick up waste material, including carbon dioxide. Capillaries pass the waste to veins, which take the blood back to the heart and lungs, where carbon dioxide is let out through your breath as you exhale.
In a way, moderate-intensity physical activity is that "magic pill" a lot of people are looking for, because the health benefits go beyond keeping your waistline trim: Not only can it reduce your risk of cancer, stroke, diabetes and heart attacks, but studies have shown that physical activity can significantly improve the moods of patients with major depressive disorders.
But in today's unenlightened "believe everything you hear" age this most effective and proven approach, for some strange reason, does not seem to attract much interest. This is no more obvious when one witnesses the "technological" revolution that is happening within the fitness industry, where a newer even more ridiculous gadget compared to the one that preceded it promises to build you the body of your dreams, with little effort on your part, "in 30 days or your money back"; where a machine that does most of the work for you is touted as a suitable replacement for actually applying a modicum of effort. https://www.youtube.com/watch?v=mDHGaU_jGrQ