Matthew 6:16-18 - “And when you fast, do not look gloomy like the hypocrites, for they disfigure their faces that their fasting may be seen by others. Truly, I say to you, they have received their reward. But when you fast, anoint your head and wash your face, that your fasting may not be seen by others but by your Father who is in secret. And your Father who sees in secret will reward you.
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If fasting is done as the above Scripture indicates you'll never know of it, but the Father will.
Any "fasting fad" would have been something of this world and not of God, IMO.
I think it is Michele Bachmann who does a fast each year.
Founded in 1977, Regent University’s 13,000+ students are studying on its 70-acre campus in Virginia Beach, Virginia, and online around the world.
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Again, I think think she holds a 40 day fast each year and invites anyone and everyone to participate. There's someplace online where you can add your name.
While I won't judge the event, neither would I ever participate.
When I fast it's between me and God.