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Most people just drink WATER when they’re fasting (adding in some electrolytes by sprinkling in a little sea salt and cream of tartar).  But there are fasts that include other ingredients. A “fast” is defined as “abstaining from all or some kinds of food or drink.” This gives some leeway for people to experiment and find an approach that works for them.

There are water fasts, juice fasts (in which one drinks only juices), fat fasts (in which one eats only fats), and protein fasts (in which one eats everything except protein… the terms can be a little confusing). (There are also  so-called dry fasts, which most fasters consider inherently dangerous and which I personally would never do.)

In my own case, I do WATER FASTING for the most part. But I also sometimes do LOW CARB JUICE FASTING (LCJF), in which I drink (mainly) water but might also drink two or three glasses of very low carb juice, either a juice I’ve made myself, or a low carb prepackaged juice that fits my specs. (Oh, and I also drink green tea and coffee.)

I’ve based some LCJF fasting around a juice made by Suja called Uber Greens.  It costs in the range of $9 to $12 for a 46 ounce bottle. It’s organic, cold pressed, and pressure pasteurized (which leaves more enzymes intact than heat). The ingredients include celery, cucumber, collard greens, lemon, kale, green chard, parsley, ginger, and romaine lettuce. An 8 ounce glass has only 7 grams of carbs and 1 gram of protein. (There are almost six glasses in a bottle.) 

I’ll sometimes also add in a source of fat such as a little cream in my coffee. Fat does not trigger an insulin response, so won’t take you out of autophagy or ketosis. 

The reason I (sometimes) do low carb juice fasting is because it’s a way of including some micronutrients such as enzymes, vitamins, minerals, and phytonutrients while fasting. Some say these aren’t needed when fasting, or might even interfere with the fast, but I’ve seen no evidence, in any of the reading I’ve done, showing that they interfere.  It’s important to me at my age (I’m an older dude, and not getting any younger 🙂 ), not to develop micronutrient deficiencies. I’ve found that low carb juice fasting can be just as effective as water fasting for my goals (keeping my weight down around where I like it, and general health and autophagy). 

It is harder for me, though, to do a several-day fast if I’m drinking some juice. I’m better off for a prolonged fast like that, only drinking water.

I should clarify that I don’t do HIGH carb juice fasting, and would not personally recommend it. A high carb juice fast would involve adding things like apple juice or orange juice, which are full of fructose, which I’m healthier when I avoid.