from what I understand, a "Daniel Fast" according to scripture is 3 weeks long and consists of only fruits and vegetables.
“In those days I, Daniel, was mourning three full weeks. I ate no pleasant food, no meat or wine came into my mouth, nor did I anoint myself at all, till three whole weeks were fulfilled.” Daniel 10:2, 3
Of course, in true American fashion, this idea is just ripe for someone to go off and write a book while making a ton of money off of it, complete with "product" testimonials:http://daniel-fast.com/http://danielfast.wordpress.com/daniel-fast-food-list/
other than no meat/meat products, none of this:
"All sweetenersincluding but not limited to sugar, raw sugar, honey, syrups, molasses, and cane juice.
All leavened bread including Ezekiel Bread (it contains yeast and honey) and baked goods.
All refined and processed food products including but not limited to artificial flavorings, food additives, chemicals, white rice, white flour, and foods that contain artificial preservatives.
All deep fried foods including but not limited to potato chips, French fries, corn chips.
All solid fats including shortening, margarine, lard and foods high in fat.
Beverages including but not limited to coffee, tea, herbal teas, carbonated beverages, energy drinks, and alcohol.
Remember, READ THE LABELS!"
(source: first link)