I am starting to think that perhaps it isn't good to fast on the sabbath (for spiritual reasons). I've heard this doctrine before, but rejected it because when on a fast more than a week long, you naturally fast on the sabbath. I was concerned that it I ate on the sabbath, I would lose the benefits of a long fast. I can think of two benefits off the top of my head:
1)When you fast you are in an Atkin's diet like ketosis. If I were careful to break it with a small enough amount of food, say a couple of grams of challah (which is bread) and a sip of grape juice (say 1/8 of an ounce - maybe with enough water added that I feel like I am drinking a glass of juice) per meal, I think my carbs would be low enough that I would stay in ketosis, so on that count I think I could do it.
2)When you fast, after a few days your digestive system stops working, and allows your body to spend its energy on healing. If I eat, it may start working again, and then may not get back to the desired resting/healing phase for a few days. This is bad, but I have also heard a doctor say that if you take an insignificant amount of calories, they still consider you to be fasting. Unfortunately, doctors don't seem to know much about fasting, so I don't feel I can take his word for it. So, what I would like to know is if my plan is OK on this count, and if not, is there something that I could eat on the sabbath that would not appreciably slow down the healing process and so allow me to honor the celebratory spirit of the sabbath.