Can Kombucha Mold Cause Cancer?

Someone asked about the potential risks of kombucha tea on Microbial Nutrition recently, citing an anecdotal report of a woman who developed pancreatic cancer after a year of drinking kombucha tea. It would be difficult to prove any causal relationship, but Bruce Stordock did post a warning about a source of carcinogens from a web page:

High acidity of the broth aside, I have seen several of my vessels spontaneously contaminate with molds. Of most concern are the species of Aspergillus I have found floating around with Kombucha. I fear that amateurs could think that by merely pulling out the Aspergillus colonies with a fork, that the culture would be de-contaminated, a dangerous, even deadly presupposition.

The water-soluble toxins of Aspergillus can be highly carcinogenic. Several species are known killers. Since the public can not be expected to distinguish a clean fermented culture from one which is not, I fear that the unreserved use of this tea will result, has resulted in illness, if not death. (See Newsweek, April 25th, 1995, pg. 6.)

(source: http://www.fungi.com/info/articles/blob.html)

At first glance, this is alarming because it implies that a culture that is supposed to be healthy could be causing great harm. However, a further look at Aspergillus does not seem to bear out these concerns.

Aspergillus is a genus representing about 200 different species of mold. Of these species, Aspergillus flavus and Aspergillus fumigatus are known to cause invasive infections in humans. Aspergillus fumigatus and clavatus are also commonly sources of allergic reactions in humans. And a type of mycotoxin called aflatoxin produced by some strains of Aspergillus flavus and Aspergillus parasiticus have been linked to cancer. (See also The Aspergillus Website which has information on Aspergillus-caused illnesses and case histories. Note that the organization is funded by pharmaceutical companies.)

In kombucha cultures, Aspergillus niger and Penicillum notatum were the most common molds found in a survey of cultures:

According to Michael Roussin, Director of the Kombucha Consumer Research Group in Salt Lake City, the two most often found molds on Kombucha are: Penicillum notatum and Aspergillus niger. Mr. Roussin's group of researchers tested many hundreds of Kombucha colonies during 1996, and during this time found that these two molds were the two they isolated from the tested colonies. According to them, Penicillum notatum is the green mold and Aspergillus niger is commonly white, black or gray.

Unfortunately, the full report containing the comprehensive list of moulds is not available for free.

Aspergillus niger is "generally regarded as safe" by the FDA, however it is dangerous to immuno-compromised people, and you should avoid breathing the spores:

A niger is the third most common Aspergillus species to cause pulmonary disease, after Aspergillus fumigatus and Aspergillus flavus. It is also a rare cause of chronic necrotizing pulmonary aspergillosis. A fermentation by-product of Aspergillus fungi, especially A niger, is oxalic acid, which complexes with calcium from the host to form calcium oxalate crystals. These crystals cause severe tissue necrosis, including damage to blood vessels.

However, I could not find any confirmed reports of other pathological species of Aspergillus in kombucha. An FDA "Talk Paper" mentions Aspergillus, but not any specific species:

The unconventional nature of the process used to make Kombucha tea has led to questions as to whether the product could become contaminated with potentially harmful microorganisms, such as the mold Aspergillus. Such contamination could produce serious adverse effects in immune-compromised individuals.

On the other hand, some species of Aspergillus are necessary for certain fermented products. For example Aspergillus sojae and Aspergillus oryzae are used to make koji and its derivatives which include miso and amazake (a sweet type of sake). Dom mentions that A. oryzae is one of the molds in sourdough starter as well.

Finally, going back to the originally posed question, kombucha just doesn't agree with some people, as Heidi notes:

People tend to react to kombucha either positively or not. On another list, several people got candida-like reactions after imbibing it. Others felt wonderful. I got some almost-migraine like symptoms once after a big glass. A fair number of people get a "niacin flush" after drinking it. There have been issues about it not getting along with certain medications (which is also true of grapefruit, BTW!).

Being exposed to carcinogenic molds does not look like one of the risks involved with making kombucha, especially if hygienic practices are followed.

Survivalism for Everyone

Survivalism sometimes reminds me of people who run away from paying taxes or are preparing for apocalypse. Fair or not, this preconception was changed by a recent mention of Tom Brown Jr on the Native Nutrition mailing list.

Tom Brown rocks! We are all avid archers now and have three of his books. Reading his story first ... well, ds is reading ALL books at once, lol. He was out tracking sugar ants and collecting to eat. I asked how such little things would be worth it. He says TB writes that a handful is as nutritious as 1 lb. of beef (or something like that, don't quote me).

and later in the same thread, from Wanita Spears:

A squirrel, rabbit, elk or any other mammal with a fur hide has a brain proportionate in size to the amount needed for a human to tan it's hide. The relationship of brain to hide to human use and need for survival, was likely one of those insights you quoted from Tom, that changed how Tom saw the world.

Tom Brown is a tracker and wilderness survival expert who has written numerous books, including a series of "field guides" such as Nature Observation and Tracking, Living With the Earth and Wilderness Survival. He also runs a school in New Jersey called Trackerschool.

An earlier thread indicates there is some controversy, perhaps rumours spread by professional jealousy:

I asked Dan about the fraud claims you mentioned. He told me he's familiar with a number of such claims, many from competitors at wilderness schools in the west it seems. Tom's school is the most well known, the oldest, and is in NJ, as I imagine you already know. As you said, what Tom Brown knows is not something one could learn from a book. He is a proven masterful tracker...

Further reading in that thread provides some fascinating reading about the abilities of Tom Brown and other wilderness survivalists. At least, for a city dweller like me!

Cod Liver Oil: Murky Contents

Triggered by an allegation of deceptive labeling, cod liver oil (CLO) has been the subject of several long running threads on a few mailing lists recently. The root cause seems to be the lack of transparency in labelling and production practises.

A post from October 2004 was the first indication that there was more than pollutants like mercury to worry about in cod liver oils. Petteri from Finland reported that the product information sheet filed with a government agency found soy product, synthetic vitamins and other additives in Carlson's cod liver oil.

Natural tocopherols (soy oil concentrate 70%), synthetic dl-alphatocopherol-acetate, retinylpalmitate-concentrate (incl. synthetic retinylpalmitate and peanut oil), cholecalciferol concentrate (incl. synthetic cholecalciferol and vegetable oil).
The lemon flavor version includes also: saccharinsolution (incl. ethanol), lemon flavor.

This vitamin E from soy is used to lengthen the shelf life of cod liver oil.

Petteri later asked Dr. Mercola (who endorses Carlson's cod liver oil) about these issues but received nothing concrete:

About a half year ago I contacted Mercola on the subject of Carlson's soy based vitamin E and the synthetic vitamin A and D used in the product. They asked for more information and after I send them some documents they went completely mute.

Recently, Pratick Mukherjee received a response from Carlson's many weeks after initially contacting Dr. Mercola. Timothy Johanek of J R Carlson Laboratories finally confirmed that Carlson's CLO contained soy-derived vitamin E. In a follow up, Johanek stated that a mixture of GMO and non-GMO soy was used, and no synthetic vitamin A or D was added. Unfortunately this contradicts Petteri's information sheet.

If that wasn't enough, the Weston A. Price Foundation stopped endorsing Carlson's Cod Liver Oil on their website in February 2005, stating "the manufacturer is removing vitamin A out of concerns of toxicity."

Removing nutrients is one thing, what about artificially increasing the levels of Vitamin A and D? There is concern among some that some CLO marketers may be engaging in this practise. For example, Petteri reports that a major CLO wholesale supplier, Lysi, cannot supply their product without fluctuations in vitamin content:

"We can offer unbleached and undeodorized cod liver oil with natural vitamins A and D. The vitamin content will however fluctuate a lot. The vitamin A can be approximately 600 - 1.500 i.u./g and the D vitamin 100 - 250 i.u./g."

Although producers may employ techniques to make vitamin levels more consistent, Petteri found that CLO marketers do not have to even bother, at least in his jurisdiction. In a conversation with a senior government scientist:

So I asked: If I add the required amount of synthetic vit. A and vit. D to a fish oil base, can I sell this procuct as cod liver oil? Would the Agency of Medicine approve it?

She said yes.

And would I have to mention the synthetic vitamins on the label?

No.

Another possibility is that the levels fluctuate in the actual product despite the implication of consistency made by the label, as Suze Fisher reported:

I have at least one assay of a batch from NF [Natural Factors] which I requested and it shows the peroxide value, as well as vits A and D potency, which can vary quite a bit from what the label states (on any brand).

Consequently, Petteri feels cod liver oils such as Nordic Naturals and Garden of Life's Olde World Icelandic, that state an approximate range, as more "honest" and convincing.

Fundamentally, it seems the companies that sell cod liver oil to consumers, the marketers, could do a better job of education and creating more transparency to their business. With a confusing plethora of terms, it's hard for consumers to know what is often-repeated myth and what's important. It is also ironic that a government-regulated informational filing in Northern Europe provided the first discussed hint of additives in one of the most reputable brands on the market.

Sometimes even the marketers aren't sure of the answers. Between fish and bottle is a mysterious process.

A Re-Designed Onibasu with New Features

We are happy to announce that we launched Onibasu.com with a whole new look this morning. We made the pages easier to read with a cleaner design. We hope you like this new look!

We also added some useful new features:

There is a new Recommended Reading section containing a selection of books that have been talked about on mailing lists. We have dug through the archives to compile people's comments for each book, and organized them conveniently to save you time. Liat will be adding books twice a week.

We have decided to create an onibasu-updates mailing list on Yahoo! groups for people who would like to know what's been added to the site. Subscribers will get a short weekly email with links to new blog entries and additions to Recommended Reading. This will serve the needs of those who are not able to subscribe to our blog by RSS. Click here to subscribe to onibasu-updates.

Finally, we made it easier to send us feedback by creating a simple form on our "Contact" page. It is anonymous (we do not capture any information about your browser or host/IP!) and more convenient than writing an email. A similar feedback form is available in the Recommended Reading section for you to comment on any book (click here for an example). Any comments you send us are appreciated!

The Early Years of Soy Debate

On the Chapter Leaders list, a reader of the recent book, "The Whole Soy Story: The Dark Side of Americas Favorite Health Food," asked how the Weston A. Price Foundation (WAPF) came to their position against soybeans and soy food products. Sally Fallon, one of the founders of the WAPF, replied that her concerns with soy actually predated the founding of the WAPF. Interestingly, she mentions that much of the damning evidence against soy was found in research that was funded by the soy industry!

... I found reports written by the soy industry in the 1970s on how they were trying to get phytic acid and also enzyme inhibitors out of the soy by processing, and how difficult this was to do. I found the Rackis studies showing the damage to the pancreas of rats consuming processed soy protein--these were industry-sponsored studies. I also found the great quote on how they were going to market soy as a health product to the upscale market, in order to then have it accepted by the general public.

For more information on the WAPF's stance on soy, see their introductory Soy Alert! page.