Is Kombucha Tea Healthy?

If you read the back of the bottled kombucha you'll find in health food stores, such as, "Kombucha Wonder Drink," and many others, the answer is most definitely yes. With all the hype, it's not surprising even some people on raw food diets are embracing so-called raw kombucha tea because you can drink it without pasteurization.

In his book, "Kombucha The Miracle Fungus," Harald Tietze praises the beverage, writing that in Qin Dynasty China, kombucha tea was, "a beverage with magical powers enabling people to live forever"(1).

With the claims so grandiose, it makes you wonder: What exactly is kombucha, is there any truth to the health claims, and is the beverage safe?

What Is Kombucha, and How Is It Made?

Kombucha, not to be confused with the tasty kabocha squash, is a fermented and sweetened beverage usually made from black tea. It's fermented with a variety of yeasts and bacteria which form a fungus sometimes referred to as a mushroom by the devoted, although it's not a mushroom.

Made at home, it usually remains unpasteurized, creating what many refer to as raw kombucha tea. The major store brands, such as "Kombucha Wonder Drink", are almost always pasteurized.

So what kind of chemical transformation is going on during the brewing process?

Kombucha is, like carcinogenic alcohol and vinegar, a product of the fermentation process.

Fermented foods and beverages were historically used by many cultures, in part to escape the ravages of contaminated water (which is why American colonists drank hard cider at most meals, ancient Greeks and Romans drank wine, and early Egyptians drank so much beer) and to preserve food for times of scarcity by halting the decomposition process via the production of microbe-killing acids.

But the finished product is often very different than its fresh constituent parts, and there are consequences to that transformation. Below are some of the more interesting acid, caffeine, and pH levels in kombucha depending on brewing methodology.

Organic Acids and Caffeine In Various Kombucha Brews (7)

Sample	Acetic Acid	Glycolic Acid	Formic Acid	Oxalic Acid	Caffeine	pH
Loose Leaf Pu-Erh	3330	2190	35	0.5	55	3.0
Pu-Erh #135	3150	722	23	2.9	102	2.8
Clipper Chinese Green	3630	445	191	12	130	3.0
Kombucha Manna	2360	129	109	10	65	3.2
Tibetan Mushroom	9443	2111	<10	56	194	2.8
Pu-Erh #135	8100	1790	<10	55	188	2.8
Unknown	2215	88	273	20	59	3.4
Twinings Earl Grey	3150	696	68	12	69	2.8
K Zoo	14200	71	25	0.6	n/a	2.8
All measurements are milligrams per liter.

High Acid Content Of Kombucha Tea

What really catches the eye in the table above is the high acid content, particularly the acetic acid.

What is acetic acid? You'll find it on chemists' shelves in containers affixed with a skull and crossbones and a warning label that tells you to ingest it under no circumstances. Acetic acid can eat through your skin, and I'm sure it wouldn't do any favors to your digestive system.

When we ingest a food or beverage with acetic acid in it, we're basically taking a bet that we've diluted it enough with water or another substance to make it safe. Table vinegar, for instance, is watered down to 2.4 to 3.5 percent acetic acid. Most people consume it irregularly in small quantities, such as a few tablespoons on top of their salad a few times a week, so there is often no overt sign of distress. When people eat it regularly and in larger amounts, though, problems like osteoporosis, hyperuricemia (too much acid in the blood), and hypokalemia (the acid has leached too much potassium from the body) can result (8).

Kombucha Tea tends to be between 1 and 2 percent acetic acid, but unlike vinegar, which is usually used sparingly, some people drink glasses of beverage daily. This raises questions about the long term safety of the drink.

The Safety Of Kombucha Tea

There's good reason to believe kombucha isn't safe. There are numerous medically-documented cases of kombucha causing severe harm, including sometimes-fatal liver dysfunction, lactic acidosis (2), gastrointestinal toxicity (3), and even anthrax infection (4).

In one set of patients, two experienced what appeared to be symptoms of allergic reaction, a third became jaundiced, and the fourth experienced nausea, vomiting, and head and neck pain brought on by kombucha tea (3).

Another concern is the brewing process. While large-scale commercial brewing operations are likely to be safe, some home-scale brewers make mistakes rendering the tea toxic. For instance, in one case, a patient used a ceramic pot that leached lead into the tea. When drunk, this tea resulted in lead poisoning (5). Raw foodists who make their own because many commercial blends are pasteurized might have issues if they do not properly stop harmful bacterias and contaminants from getting into the tea.

One set of researchers, after reviewing the studies on Kombucha and the available case studies, concluded that, "While Kombucha tea is considered a healthy elixir, the limited evidence currently available raises considerable concern that it may pose serious health risks. Consumption of this tea should be discouraged, as it may be associated with life-threatening lactic acidosis (2).

But Doesn't Kombucha Improve Health?

A lot of impressive health claims are thrown around about Kombucha, but so far there's no evidence to support them. The drink has not been heavily studied, but of the handful of human trials, none have shown any significant benefits. Trials on rats are mixed between mild benefits and no benefits.

No significant new research has emerged since a 2003 review of all the studies on Kombucha. That review concluded, "...the largely undetermined benefits do not outweigh the documented risks of kombucha. It can therefore not be recommended for therapeutic use. (4)"

Raw Kombucha Tea: There's A Better Way

People drinking raw kombucha tea thinking it will heal or invigorate them are making the same mistake many do: assuming outside forces heal the body. Only the body heals itself, and it will do so when we supply the conditions and forces that allow it to get on with the work.

This rather damning praise from a growyouthful.com article on kombucha shows the mindset:

Is Raw Kombucha Tea Healthy?

What Is Kombucha, and How Is It Made?

High Acid Content Of Kombucha Tea

The Safety Of Kombucha Tea

But Doesn't Kombucha Improve Health?

Raw Kombucha Tea: There's A Better Way

Following Up:

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