I think it's good when you find those things, events, time or circumstance or just internal desire that prompts a person to want to fast. It's probably healthy to have things more important than food and drink, and there fore willing to be sacrificed for a period of fasting.
A scripture that I think talks about fasting in a very inspiring and interesting way is:
Mark 9: 24 A father came to Jesus with a child who was possessed of a devil. Christ's disciples had been unable to remove or evict this particular spirit. So now the father implores Jesus. Vs 23: "Jesus said unto him, If thou canst believe, all things are apossible to him that bbelieveth. and then vs 24 "And straightway the father of the child cried out, and said with tears, Lord, I believe; help thou mine aunbelief." A few profound lessons from this. The father of the child did believe, but there was that part of him that couldn't. That part of him that wanted to believe and exercise great faith but was coming up short. So he humbly acknowledges his unbelief, and asked Jesus for help. Since Christ is the "Author and finisher of our faith" This pleading to the Lord seems very appropriate and in a sense this situation represents all of us.
After Christ did remove this "foul" spirit, the disciples asked him why they had been unable to. His response is in vs 29 "And he said unto them, This kind can come forth by nothing, but by prayer and afasting.". (if you rest the mouse pointer over fasting in that last sentience the topical guide reference will pop up and makes a very interesting connection. Fasting is perhaps God's suggestion for problem solving.
Happiness is found when the flesh is subordinated to the Spirit. Fasting is one way to do that. It's a call to proceed personally and remember what lies beyond the veil, something we all once knew but only a few can now remember. Fasting is a way to begin to remember, and a way to find guidance back home.
From verse 29 it appears that fasting not only helps the individual, but also has an effect on others, and has an effect on the adversary and those with him. Prayer and fasting causes some types or forms of evil to "come forth".
Knowledge is indeed power.