Have you ever fasted before? I mean not eaten a meal or two as spiritual discipline? (Of course you can fast from other things, but most see fasting as not eating.)
I can't recall ever hearing a sermon on the importance of fasting as a spiritual discipline. It's not talked about much in Christian circles and I know Christians who have never practiced the discipline of fasting.
But fasting is close to my heart. I've practiced the discipline of fasting for about 13 years. I've fasted one meal, two meals. I've done a 22 day juice fast for spiritual reasons. I've done partial fasts. I've fasted for breakthroughs in my own life. I've fasted for other people and I've done corporate fasting.
Now in saying this, I am not at all wanting to say, "Oh look at how spiritual Heather is for fasting!" I tell you this as a way of encouragement. Actually, I believe fasting should be a very private matter, between you and only those people who many be effected by you fasting.
Whenever I fast, God does amazing things. I see what controls me. I see what's inside so much clearer! God revels much to me when I fast and I feel so much closer to God when He calls me to fast.
If you have never fasted then I encourage you to pray about if or when you should fast. Look up scriptures on fasting and some of the reasons people fasted in the bible. See what Jesus says about fasting.
There are a couple of great books you can read: A Hunger for God by John Piper (I HIGHLY recommend this book!), and The Celebration of Disciple by Richard Foster.
I would say that if you are looking for a breakthrough in your own life and have not looked into fasting, then pray and ask if God is calling you to fast as a spiritual discipline!
If you feel for medical reasons you are unable to fast from food, then seek God about something else you can fast from (cell phone, computer, TV, video games). I do not recommend fasting for anyone nursing or pregnant, as well as others with medical conditions that require you to eat food a certain number of times per day.