Focusing on human-microbe relationships

Recent advances in DNA sequencing techniques in the fields of biology and medicine have led to a greater focus on the role of microbes on human health. Synthetic chemicals that are added to foods and hygiene products can affect the relationship between microbes and humans and human health.

Recent research conducted at UC Davis involving human and animal health and the issue of microbes is leading researchers to issue cautions about the excess use of synthetic chemicals, such as triclosan, in human hygiene products.

“One of the [perspectives] that we’re looking at most recently is how the environment and diet might affect the bacteria that live within us,” said Bruce German, a professor in the UC Davis Food Science and Technology Department, in reference to his work with UC Davis professor Bruce Hammock.

Hammock does research in the UC Davis Center for Environmental Health Science and has been conducting research with two UC Davis graduate students, Ray Zhang and Erika Fritsch.

“The chemical triclosan is found in numerous consumer products, like in antibacterial soap, face wash and toothpaste, and we are constantly exposed to this chemical through the products that we use,” Zhang said.

Researchers are concerned about the overuse of antibacterial soap and other hygiene products, since such overuse may lead to bacterial strains that are resistant to the synthetic chemicals used.  The existence of bacterial strains that exhibit resistance to common antibacterials can potentially lead to problems in public health and increased rates of infections.

“We are beginning to realize that the cloud of microbes that live in and on us and that live in and on plants and animals have profound effects on many aspects of our biology,” said Jonathan Eisen, a professor and researcher in the UC Davis Genome Center. Eisen recently gave a talk on TED.com titled “Meet your microbes.”

According to Eisen, widespread use of antibacterials is being viewed in a completely new light.

Leo Galland is the director of The Foundation for Integrated Medicine and author of the book “Power Healing: Use the New Integrated Medicine to Cure Yourself.” Galland agrees with Eisen’s assessment.

“Doing things randomly [can] destroy bacterial communities without a real clear idea of why you’re doing it [and] can definitely lead to unintended and adverse consequences,” Galland said. “It’s not necessarily a question of good bacteria and bad bacteria, because the functions of bacteria – the metabolic activities and the immune effects of bacteria on the human body – depend upon the specific milieu in which that interaction is taking place. So a particular organism might have beneficial effects in one milieu and negative effects in another.”

Galland stresses that “bacteria need to be treated with respect and we need to basically understand that our bodies are like planets.”

“We should continually be evaluating the benefits of [synthetic] chemicals and the [associated] risks,” stressed Hammock.

BRIAN RILEY can be reached at science@theaggie.org.