New Insights Into the Benefits of Probiotics
It’s been obvious for some time that probiotics are generally good for one’s health. Probiotics are live microorganisms that thrive in foods like active-culture yogurt and other fermented foods—and one’s gut. That’s because these acid-loving bacteria are able to survive the harsh, acidic environment of the stomach, pass through into the intestines, and live there in colonies. These colonies help keep you—the host—happy and healthy.
Research shows these benefits are literal: People with healthy, diverse communities of friendly bacteria (the gut microbiome) have stronger immune systems and are less susceptible to depression and other mood disorders. Thus, a happy healthy gut microbiome literally means you yourself will be happier and healthier.
We’re learning more every day about this previously mysterious hidden world within out bodies. Now, researchers at the University of Maryland Medical Center/School of Medicine have shown that one common probiotic, Lactobacillis rhamnosus GG (LGG), may benefit health by contributing to the overall health of the gut microbiome itself. Some research has suggested that LGG may help with intestinal problems, respiratory infections, and certain skin disorders. It may even help with weight loss.
But scientists have wondered how, exactly, it manages to do so many things. Now, they think they know. LGG appears to behave as a facilitator, modulating the activity of other beneficial species of gut bacteria. Claire M. Fraser, PhD, is a professor of medicine at UM/SOM. "This species of bacteria has a reputation for being really useful to humans," said Prof. Fraser. "So we wanted to better understand how it might work in the human intestine.”
Working with elderly subjects, she and her team gave LGG to subjects twice daily, for one month, and then examined the effects this had on the makeup of subjects’ gut microbiomes. LGG appeared to influence the health and activity of numerous other species of bacteria in subject’s guts. "This is a new idea, that some probiotics may work by affecting the overall ecosystem of the gut," said Prof. Fraser. "Previously we tended to think that LGG and other probiotics worked directly on the host. I think this finding has many exciting implications.” Among other implications, Fraser believes her research shows that we need to start thinking about the entire ecosystem of the gut microbiome when considering its effects on human health, rather than focusing on individual species of bacteria.
Emiley A. Eloe-Fadrosh, Arthur Brady, Jonathan Crabtree, Elliott F. Drabek, Bing Ma, Anup Mahurkar, Jacques Ravel, Miriam Haverkamp, Anne-Maria Fiorino, Christine Botelho, Irina Andreyeva, Patricia L. Hibberd, Claire M. Fraser. Functional Dynamics of the Gut Microbiome in Elderly People during Probiotic Consumption. mBio, 2015; 6 (2): e00231-15 DOI: 10.1128/mBio.00231-15