2011 Science News of the Year: Genes & Cells
By Science News
Nicolle Rager Fuller
Boons and busts via gut microbes
Studying the secret lives of bacteria living in human intestines has yielded some unexpected finds. One study suggests that most humans have one of three different combinations of friendly microbes (SN: 5/21/11, p. 14), and another reveals that people’s mix of microbes depends heavily on diet. Changing the ratios of nutrients consumed tweaks the composition of the microbial populations in the guts of mice carrying human bacteria, scientists find (SN Online: 5/19/11).
Knowing just how to alter the diet to achieve the right mix of microbes may be important for good health, both physical and mental. At least one type of friendly bacteria can send signals from the intestines through the vagus nerve in the neck to influence brain chemistry and change behavior in mice, researchers report (SN: 10/8/11, p. 9). Gut microbes have also been found to convert a type of fat found in meat and dairy products into an artery-clogging chemical, and intestinal microbes may trigger multiple sclerosis, an immune system disorder in which the body attacks its own nerve cells (SN: 12/3/11, p. 11).