The Russians launched an investigation, right after WW2, to discover why cancer was on the increase in their country. After the Bolshevik Revolution and continuing thru WW2 Russia had experienced tremendous industrial growth. Factories and giant industrial cities were springing up all over & smokestacks were belching industrial smoke and vapors into their atmosphere. Industrial growth and increased military might was the goal with no concern for the environment. Easily compared to the pollution in England when their industrial revolution was in full swing. Doctors, scientists and other investigators were sent to various parts of the USSR to run tests and investigate the causes of the Cancer problem. During the investigation they found 2 areas ( the Solikamsk & Berezniki districts) that were almost cancer free. (The few cases of cancer found in these 2 areas were newcomers who had just settled there).
The answer was….Tea Kvass (aka Kombucha) (but not to be confused with the kvass drink made from fermented bread). Not only were the people in these two regions cancer free, they were healthier and had longer life spans. Hundreds of years before, the Czar had been introduced to Kombucha by learned travelers that had brought it back from China. After a while the Czar remarked that this tea wine was no longer to his taste and instructed that it be given to the people. His comment was that now even the little Moujiks could make their own wonderful tea wine and would stop being covetous. Apparently these 2 areas had been making and consuming tea kvass (aka Kombucha) ever since. The intense Soviet investigation, coupled with other large bodies of evidence indicate that Kombucha is indeed a dramatic immune system booster and body detoxifier. A research facility was readying a batch of Kombucha for Stalin (he frequently had nightmares about dying from cancer). But the KGB accused the Jewish personnel on the project of attempting to poison Stalin, and the treatment was abandoned. We know better today. The most that the FDA has said about Kombucha is that it won't hurt.
How does it taste??
Well, it tastes a lot like a tart cider. Hard to describe until you try it. It can be made very strong and it will taste like vinegar, or it can be made fairly weak and it will taste like apple cider. It all depends on your taste and what you like. Once you get used to the taste, you will probably start making it stronger and stronger, as you enjoy the taste as your morning drink.
How to Brew:
pour 3 quarts of water in a glass, porcelain, or stainless steel (not aluminum) pot and bring it to a rolling boil. Let it boil for 10 minutes. Add 1 cup of regular, granulated cane sugar and stir until the sugar is dissolved. Next, let it boil for 5 minutes more. Add 1 family size (quart) tea bag, or 4 individual teabags, or 2 tablespoons of loose tea. Tea bags are easiest and recommended. Cut black tea (orange pekoe & pekoe) such as Lipton, Tetley or a house brand is the best. If you already have a sensitive stomach you can temporarily use Oolong or green tea which is easier on the stomach but most believe it is not the most effective. You can always switch to the black tea after your stomach improves. Cover the container and let it steep for ten minutes. Steeping for longer won’t hurt anything, but the tea will be a bit stronger. You can then remove the tea bags and allow the prepared tea to come to room temperature. Selection of a fermentation container is most important. Clear, unleaded glass is best while plastic and metal containers should be avoided, though food grade plastic can work. The mushroom must breathe so the container must have a wide mouth such as a mixing bowl and hold 3 quarts minimum with 4 quarts being best. I have found several types of containers such as glass ice buckets, sun-tea jars, decorator and serving bowls at discount and department stores ranging from $5 to $12. Remember the first thing the mushroom does is to expand to cover the surface of the tea so a small mouthed tall container will only produce a small mushroom. A short container with a wide top produces the most effective tea in the shortest time. A bowl that is 8’’ in diameter or more is preferred. Pour your room temperature (warm or hot tea will damage or kill the mushroom) into the fermentation container. Add 4 to 6 ounces of your old tea or the tea that came with your mushroom. Carefully add the mushroom, yucky side down, and cover the container with unbleach! ed musli n or cheesecloth held firmly in place by a wide rubber band. The fermentation process does produce a distinct smell (similar to vinegar or apple cider) that might attract little creatures such as fruit flies, ants or common house flies. Pests could contaminate the batch so make sure the cover is tightly in place. Put the container in a place (out of direct sunlight – hopefully a closet) where it can sit undisturbed at normal room temperature for 8 to 14 days. You can do a taste test anytime after 8 days to see how it's coming along. After 8 days, it will just be to your taste. Its taste becomes more acidic as it ferments longer so find where you like it and bottle. During the fermentation phase you can peek at the mushroom thru the glass to check on progress but try not to disturb it by moving the container. Try and avoid smoking in the room that contains the mushroom. At the end of the 8 to 14 day fermentation phase you are ready to harvest your finished brew and start a new batch. Some don’t like the idea of putting their hands in the tea or may be squeamish about handling the mushrooms so you may want to use latex or thin plastic food handling gloves. If everything went according to plan you will now have 2 mushrooms. You are now ready to start the process over again. For greater carbonic acid and less tang pour up the tea in 8 to 10 days. For weight control allow the tea to ferment for more than 10 days and drink a glass before each meal. Kombucha can be kept in the refrigerator which slows further fermentation. At room temperature it will become stronger tasting and the yeast spores will start forming a mini-mushroom on top which is not a concern. If the tea gets too strong then simply dilute it with a little of your new fresh-brewed tea to suit your taste. 
I have a lot of more technical information, if you are interested, but I already put a ton of info in this ad and don't want to bore everybody. Send me a note if you would like more information, or if you have any questions.
DISCLAIMER: The information presented is for information purposes only. It is based on scientific studies and or traditional usage. Consult a health care professional before using supplements or making any changes in prescription medications. The information and statements contained herein are not intended to diagnose, treat, cure or prevent any disease.