News FocusMicrobiology

Girth and the Gut (Bacteria)

See allHide authors and affiliations

Science  01 Apr 2011:
Vol. 332, Issue 6025, pp. 32-33
DOI: 10.1126/science.332.6025.32

You are currently viewing the summary.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution


Five years ago, researchers made a surprising discovery: The guts of obese mice and people harbor an array of microbes different from that of their lean counterparts. Moreover, when they gave lean mice certain gut-dwelling microbes, the rodents became fat. The findings fueled popular speculation that manipulating gut bacteria might keep weight down in people. Another researcher who was struck by how successful farmers are at increasing the growth rates of livestock by adding low doses of antibiotics to their feed began to wonder whether antibiotic use, particularly in children, might affect the long-term establishment of a balanced microbial community in the human gut, eliminating bacteria there that could help ward off obesity. He and several other groups started conducting mouse studies to examine the hypothesis. These and other intriguing obesity-related findings were presented at a meeting last month on the microbiome, the bacteria that live inside the guts and other tissues of animals. Yet many in the field caution that it remains difficult to determine whether changes in gut microbes drive or contribute to obesity or whether the excess weight itself triggers those changes.