A new study from the University of North Carolina School of Medicine reveals some gut microbes increase the absorption of dietary fats, allowing the host organism to extract more calories from the same amount of food.
The study was carried out in zebrafish, which are optically transparent when young. By feeding the fish fatty acids tagged with fluorescent dye, according to PharmaMicro, the researchers were able to directly observe the absorption and transport of fats in the presence or absence of gut microbes.
The study, undertaken by the University of North Carolina School of Medicine, revealed that microbes can promote the absorption of dietary fats in the intestine and their subsequent metabolism in the body. This means that we actually share our meals with a vast community of microbes waiting within our digestive tracts.
The Examiner notes that the research also showed that one group of bacteria, called the Firmicutes, were key in increasing fat absorption. They also found the abundance of Firmicutes in the gut was influenced by diet: fish fed normally had more Firmicutes bacteria compared to fish that were denied food for several days. Other studies have linked a higher relative abundance of Firmicutes in the gut with obesity in humans.
The implication is that diet history could impact fat absorption by changing the abundance of certain microbes, such as Firmicutes, that promote fat absorption.
One of the lead researchers, Steve Farber , is quoted by Carnegie Science, as saying:
"The unique properties of zebrafish larvae are helping us develop a better understanding of how the intestine functions with the goal of contributing to ongoing efforts to reduce the impact of diseases associated with altered lipid metabolism, such as diabetes, obesity, and cardiovascular disease. Our collaboration with the Rawls lab is now focused on how specific gut bacteria are able to stimulate absorption of dietary fat. We hope to use that information to develop new ways to reduce fat absorption in the context of human diseases."
The research was published in the journal Cell Host& Microbe. The reference is:
Ivana Semova, Juliana D. Carten, Jesse Stombaugh, Lantz C. Mackey, Rob Knight, Steven A. Farber, John F. Rawls. Microbiota Regulate Intestinal Absorption and Metabolism of Fatty Acids in the Zebrafish. Cell Host & Microbe, 2012; 12 (3)