Online since 24 years. Founded 1996 by Günther W. Frank
I am occupied for years with Kombucha but I have heard only of a few cases where any side-effects occurred. They include a slightly upset stomach and are eliminated by ceasing use of the Kombucha beverage and often in the case of digestive problems by drinking the beverage with meals. These side effects seem to be a cleaning reaction, often called a "healing crisis" by Western herbalists. In these cases I am sure it is the right way to lower the daily dosage of Kombucha and increase the tea slowly. Symptoms of the kind you mentioned could to my view be caused by three reasons:
Feeling sick and unwell generally could be allergic reactions. For an indeterminate number of allergic individuals predisposed to acid sensitivities the organic acids in Kombucha could conceivably produce an allergic reaction.
Another explanation could be that this problem might be caused by cytokine activity due to over-stimulation of the immune system (just simply lower the daily dosage)
Moreover the effects can be due to disease and weakness of the kidney and bladder. When we realise that the kidneys are filters, which extract certain poisonous material from the blood, which they eliminate from the body through the bladder, it should not be difficult to understand that these organs may be overworked by the flood of toxic material due to the detoxification of Kombucha, that they may be forced to eliminate too much poison. Kombucha is said to loosen (detach, degrade) the storage of poisons in various parts of the body which result in rheumatism, arthritis, lumbago, neuritis, neuralgia, gout, etc. If the kidneys do work insufficient, they cannot eliminate (remove, discharge) detoxification that is initiated (induced) by Kombucha.
Diseases of the kidneys, and the urinary tract, can be due to the eating of too much meat, fish, chicken and eggs, and the drinking of coffee and alcoholic beverages. The weakening of the kidneys causes a great deal of poisons which should be eliminated by them, to be thrown back again into the blood stream. The blood then attempts to throw these poisons out through the lungs, skin, bowel, and so forth. There is one cure for kidney trouble, and its results, and that is a more natural diet, particularly less animal food, also exercise, long walks, deep breathing etc. The cure of kidney trouble is not to be accomplished in a day however, it is often a very slow affair. A year be required before a complete cure is effected. Two or three months of correct living, especially with regard to diet, will make a great difference, and within a year at most, a complete and permanent cure should be accomplished.
Since Kombucha is not a standardised "medicine" prepared under strictly controlled conditions, often no scientific claims or exact explanations can be made. Explanations for the benefits are empirical, i.e. relying on observation and experiment, not on theory.
If any person is dealing with a serious physical problem, he or she should work with a trusted health practitioner. In addition, they should get acquainted with their body, learn its needs and responses. Everybody is the best judge of what affects him/her and how it makes him/her feel.