It's helpful to be clear about why you are fasting.
Set a goal for yourself and stick to it, come what may. For you will be tested. Every emotional bonding moment in your past that has some relation to food will make its way into your world. A great dinner you had once with loved ones...that special and fun bar-b-que...an awesome breakfast on a sunny morning with the family... All of these and more carry with them the deep-seated happy spots of your life. They then become triggers to old behaviors and dietary paradigms you may have outgrown or simply left behind. You smell a favorite food and all the associated and very deep feelings of satiation and joy activate in your core making for a resonance draw. This becomes your pull, which on an inner level says, "eat that food and have those times and feelings again."
Of course this cannot be. The past is gone. Yet the experience and feelings remain all of your days. So do the triggers connected with such times.
When this happens, take a moment and tell your mind, body, and soul that you recognize what is happening and - for the good of all - are establishing a new reality based upon clarity and spiritual reason. Once you do this, the power of the past over your current reality will begin to fade and lose its strength.
This is very important. Because it indicates the soul so involved is seeing how things work and is taking those steps to dictate a better future for the mind, the heart, and the path of life as guided by the divine rather than the predicatable and programmed patterns of what was and in fact, can no longer be. Ever again.
Take special note of the above and grow. Or, ignore it, and be the same old easily played programmed robot you've always been. And how has that worked out for you? You know, being a droid of social and mental conditioning of the controllers who seek to make all mankind a slave for their purposes.
With fasting, regardless of the motive in action, take advantage of that clearing and cleaning time to make a new you, under the loving hand of God.
I mean, why not?