One famous quote about fasting can be found in the Bible, when Jesus says that only prayer and fasting can chase away certain "demons" (Matthew 17:21). Whether or not you agree with this sentiment, there is a common belief that fasting, if done correctly, can definitely improve the emotional and spiritual well-being of a person.
The two main types of fasts are fresh juice fasts and water fasts.
Benefits of a water fast
Faster results than fresh juice fast
Ketosis after 2 days of water fast (ketosis is when your body burns fatty tissues instead glucose)
At 8:50 in the following video, Dr. Michael Klaper talks about the emotional benefits of water fasting:
Juice Fasting for Stress Relief
Benefits of a juice fast
Easier than a water fast
Juice fasts can last longer than water fasts
Juice Fast Success Story
The below snippet is from www.freedomyou.com. The author was going through a collapsing marriage, and was experiencing severe panic attacks. While on a juice fast, his stress was significantly reduced.
"Just the decision to fast triggered a physiological change within me. The many years of practicing fasting had created a renewal mindset, and I could already feel my body relaxing in preparation. Within the first 24 hours of the fast, my metabolism slowed down and the muscles in my neck began to soften. A day or two later, the veins on my forehead started to disappear for the first time in months and my blood pressure lowered. Entering deeper into the fasting state, I could literally feel the pressure in my body decompress. Unlike the slow buildup of months of stress, the release was quick and remarkable. The contrast allowed me to realize just how stressed out I had become and it became clear why I was experiencing so many health issues. The third night of the fast I enjoyed uninterrupted sleep, awaking clear-minded and refreshed. That morning, while washing fruit and vegetables for juicing, I knew that I had turned an important corner. Standing at the sink, I began weeping with a real sensation of joy, something I had not felt for a long time.
It’s been months now since my fast and I've had no more panic attacks. My forehead veins are invisible, neck pain is a distant memory, and my mind is focused and productive. No more uninvited tears and too-loud laughter. It was like a reset button was pressed. The best part of this lesson is knowing that when I start to feel the symptoms of stress coming on, I have something better than any medication to fall back on. Fasting as a backup stress management program is better than owning a tranquil cottage on a lake!" (Link)