Yesterday’s San Francisco Chronicle had an article on fermented foods in the Bay Area: the fermentation festival, sauerkraut, kimchi, and so on. (No discussion of yogurt.) I especially liked this:

Leaving foods unrefrigerated for two weeks or more can be disturbing to those who weren’t raised with a crock of pickles in the hallway. But U.S. Department of Agriculture research service microbiologist Fred Breidt says properly fermented vegetables are actually safer than raw vegetables, which might have been exposed to pathogens like E. coli on the farm.

“With fermented products there is no safety concern. I can flat-out say that. The reason is the lactic acid bacteria that carry out the fermentation are the world’s best killers of other bacteria,” says Breidt, who works at a lab at North Carolina State University, Raleigh, where scientists have been studying fermented and other pickled foods since the 1930s.

Breidt adds that fermented vegetables, for which there are no documented cases of food-borne illness, are safer for novices to make than canned vegetables. Pressurized canning creates an anaerobic environment that increases the risk of deadly botulism, particularly with low-acid foods.

Nothing about fermented — also called aged – meat. The last taboo. I believe we like umami flavor so that we will eat more bacteria-laden protein. (Glutamate, which produces the umami flavor, is a protein breakdown product.) All meat producers, as far as I know, age their product 2-3 weeks to improve the flavor. Understandably, they don’t like to talk about it.

Thanks to Ashish Mukharji.

Handbook of fermented functional foods, second edition, 2008.

Presenting new findings and interpretations that point even more clearly to the important role fermented foods play in our diet and overall health, this second edition demonstrates the current knowledge of fermented food production and reflects the growing credibility of probiotics in health maintenance.

You can read a lot of it online.

A study published last year in Oncology Reports found that fermented noni (an Asian fruit) juice fights cancer in rats.

Noni (Morinda citrifolia) has been used in traditional Polynesian folk medicine for more than 2,000 years. Recently, researchers have discovered that Noni juice has the ability to destroy cancerous tumors. . . .

The researchers evaluated Noni’s ability to both prevent and treat cancer. In the prevention study, female mice were injected with one of three substances: fNE, a phosphate-balanced solution (PBS, which is similar to saline solution), or lipopolysaccharides (LPS, a natural toxin found in bacteria and in fermented Noni juice) for three days. Then the researchers injected the mice with lung cancer and sarcoma cells. In the treatment study, the mice were first injected with the cancer cells, and then treated with three doses of fNE [fermented noni exudate], LPS [lipopolysaccharides], or PBS [phosphate balance solution].

A fter the mice were injected with fNE, they developed greater numbers of immune cells such as granulocytes (a type of white blood cell) and natural killer (NK) cells, indicating that fNE had stimulated their immune system. A month after receiving fNE for sarcoma treatment or prevention, more than 85 percent of the mice were not only alive, but also cancer-free. fNE also was effective against lung cancer tumor cells, although the tumor prevention rate was slightly lower (62 percent). Meanwhile, all of the mice that received PBS or LPS died.

Emphasis added. It is telling that they used fermented noni juice rather than plain noni juice; apparently plain noni juice is less effective. Fermented juice has many more bacteria than plain juice; it makes a lot of sense that the fermented bacteria stimulate the immune system.

Thanks to Peter Spero.

From a UCSF press release:

In the first effort of its kind in the United States, researchers at the University of California, San Francisco have launched a study to determine whether giving active probiotic supplements to infants can delay or prevent asthma in children.

The intervention is a novel method for the primary prevention of asthma with enormous potential to have a public health impact, said Michael Cabana, MD, chief of the Department of General Pediatrics at UCSF Children’s Hospital and principal investigator for the study. There currently are no known ways to prevent asthma, he said.

“It would be a great thing to be able to prevent asthma,” Cabana said. “We believe that using probiotics is a safe and effective way to do that.”

The press release is from May 2006; the three-year study should be almost finished.

Thanks to Steve Hansen.

One reason I believe we are vastly bacteria-deprived (and thus greatly benefit from fermented foods) is the efficacy of hookworm therapy: Hookworm parasites can reduce autoimmune diseases. Hookworms, like fermented foods, stimulate the immune system in a chronic, harmless, low-level way. Here is a good introduction to the subject:

Musician Scott Richards and artist Debora Wade are two Bay Area patients on the hookworm treatment. Richards and Wade both suffer from an inflammatory bowel disease called Crohn’s. When faced with using a parasite as therapy, both patients felt they had nothing to lose. . . . Both Richards and Wade say they didn’t have to wait long to feel relief. Richards [described] waking up and the pain suddenly gone. For Wade, she needed to be reinfected, but today said she can eat foods that patients with Crohn’s could never eat: pizza & Thai food for example.

Related story.