At a ratio of 10-to-1, the number of bacteria in the human gut far exceeds that of cells in the gastrointestinal tract. In a new study, investigators have demonstrated that the type of microorganisms in the gut plays a role in determining people's weight.
According to estimates, there are between 500 and 1,000 species of bacteria living in the human gut. These species interact in a very dynamic manner, and have a tendency to change over the course of a lifetime. This means that the effects they produce are not always the same.
The relationship we have developed with these organisms is mutually beneficial. In addition to boosting our immune system, these bacteria also help us break down multiple types of nutrients, allowing us absorb what we need from multiple types of foods. This would be impossible without our companions.
Scientists have long since hypothesized that these microorganisms play a subtle, yet important role in maintaining health and regulating weight in humans. However, since the influence is hard to decipher, experts have had a hard time figuring out how this works.
A team of experts at the Arizona State University
(ASU) Biodesign Institute (BI) Swette Center for Environmental Biotechnology, led by researcher Rosa Krajmalnik-Brown, has recently took important steps towards shedding more light on this correlation.
Details of the research she and her colleagues carried out were published in the latest issue of the medical journal Nutrition in Clinical Practice. Mayo Clinic Division of Gastroenterology expert John DiBaise worked closely with Krajmalnik-Brown on this investigation.
The group was especially interested in figuring out how bacteria in the gut influence energy regulation and nutrient absorption. “Malnutrition may manifest as either obesity or undernutrition, problems of epidemic proportion worldwide,” the team leader explains.
“Microorganisms have been shown to play an important role in nutrient and energy extraction and energy regulation although the specific roles that individual and groups/teams of gut microbes play remain uncertain,” she adds.
The team learned that bacterial communities vary in composition and species they contain depending on each person's age, body weight, the type of foods they consume, the drugs they use and a wide variety of other influences.
This investigation appears to suggest that treating nutrition-related maladies such as obesity may soon become easier, thanks to therapeutic approaches that influence the composition of gut bacteria cultures.