The good and bad of kefir (both dairy kefir and water kefir) are:

• Good: very powerful and can really fix a troubled gut
• Bad: you need to start with very small doses, such as a tablespoon once or twice per day, and build up gradually over a week or two. Once you can handle a small glass at one time, you should be able to stop worrying about dose size.

If you have a lot of "bad guys" in your gut, kefir is strong enough to crowd out the bad microbes and you may experience a die-off which may or may not explain the symptoms you experienced.

If you tried dairy kefir, is it possible that you are lactose intolerant? I drink water kefir to avoid that problem. I drink 2 bottles per day.

I'm frustrated myself at this stage - I'm 12 months on milk kefir and it gives me terrible pain. I tried everything from 1 table spoon to more than half a litre a day. Pain certainly goes away when I stop it, but then gradually comes back when I start kefir again. I don't really want to stop drinking kefir - I love it. But what concerns me is that people say it's up to a month to get used to it - no way, I'm a year on it now!

Just frustrated, really.

The Holy Bible including the Holy Koran recommends to abstain from eat fermented food such as leavened bread during certain times of year, and for a certain period of time. Breads of those days were fermented by natural means, such as what we refer to today as sourdough. Whether or not this is divine intervention or the outcome of the ancients with good observation, either way, I take this issue serious enough to follow this recommendation. From personal experience with extensive fasting in my time, the body through the process of fasting, can perform specific functions that benefit the organism as a whole. A somewhat similar process, or a branch off of bodily functions are responsive only where abstaining from fermented foods is involved, I feel. Culture food product although organisms mostly product beneficial compounds, there are possibly certain compounds produced by friendly organisms, that may impair the human organism, where overindulgence, or too regular indulgence is involved.

In Tibet, I believe, where kefir grains are referred to as Tibetan mushrooms, a suggestion exists that explains to take 2 cups of milk kefir daily for 20 days, and then abstain for 10 days. This cycle is repeated on a continuous basis [Note that kefir grains and Tibetan mushrooms are the same mother-culture as explained in FAQ 34].

http://users.chariot.net.au/~dna/kefir-faq.html

Either you've got problems with one of the proteins in the kefir, sugars if any are in there (ie. flavored ones, like peach), or the bacteria in the kefir are waging war with the bacteria in your gut.

Try to make coconut water kefir using a small amount of plain, unsweetened, kefir from the commercial stuff as a seed. If you have no reaction, then it's the proteins you've got a problem with.

Mind you, you could make your own kefir, it's pretty easy.

I am also getting pains in my stomach after taking' water' kefir.

Have you tried Kefir from goats milk?

I've had a similar problem. I started making my own from grains in milk. I was on it for a few months consuming a cup or more daily in a vegetable/fruit smoothie, then I started getting stomach pain/pressure on my left side. I've had suspected ulcers years ago and though they were returning, though the pain was different. I stopped the kefir and went on dgl, mastic, and oil of oregano for two weeks thinking maybe it was H. pylori problems. Everything cleared up and I figured I'd give the kefir another shot after about a month of no problems. So I restarted my grains and after a few batches started drinking it again. The same pain/pressure returned, so I'm off again. I'm thinking maybe the culture changed flora proportions over time and perhaps has more yeast or something that is causing the problems. I'll give it one more shot but may have to stop with Kefir all together. Interestingly, store bought doesn't cause the problem for me, only kefir that I make from my grains.