I used to perform this spiritual exercise on a regular basis usually 1 week at time for at least 2x per year, but have fallen off the wagon for many years now. I’ve been considering this spiritual discipline again – it made me more attentive and reflective instead of being verbally out of control. I recently listened to a talk show guest who fast at least once per month as a way to detox his body. A three week fast is a challenge but my view is anything that a person really wants to accomplish they can. I found it important to have a reason for fasting,(i.e. gain control food cravings; spiritual enhancement), it helped me to complete the fast. I’m looking forward to hearing of your success.