It really does work for me. The Bible, in Matthew 6:18 says, "so that it will not be obvious to men that you are fasting, but only to your Father, who is unseen; and your Father, who sees what is done in secret, will reward you."
and Matthew 6:16 says, "When you fast, do not look somber as the hypocrites do, for they disfigure their faces to show men they are fasting. I tell you the truth, they have received their reward in full."
Remember that when you do this, fasting and prayer work together. I make it a habit that when I get hungry while fasting, I pray. I simply tell God how wonderful He is and ask Him to take my hunger from me and to help me lose the extra weight I have gained.