My understanding of fasting is not eating anything, neither food nor water. I mean not putting anything in your mouth that will go to your stomach. Now I read some of your responses on fasting and I’m puzzled to a point of slight disagreement. You mentioned Daniel fasting for 21 days but I don’t see in the Bible that being declared as fasting. To me that was just Daniel’s decision to avoid eating defiled food offered to idols by Babylonian King. Fasting to me is purely not eating anything, and if someone is not eating certain foods while eating others that’s not fasting.
Complete abstinence from any kind of food and drink is the most severe form of fasting, but it’s not the only one. The dictionary gives two definitions for fasting. One is to abstain from all foods, and the other is “eating only sparingly or of certain kinds of food, especially as a religious observance.” Daniel’s decision to refuse the King’s food (Dan 1:8) and just eat vegetables and water (Daniel 1:12) would be considered fasting according to this definition. The same was true when he abstained from meat, wine and lotion for his skin for 3 weeks (Daniel 10:2), which is the incident to which I was referring.