If you're looking for a reason to ditch meat and dairy, take a look at what some Harvard University scientists discovered about the impact animal products have on gut bacteria--and our health.
The report, published in the recent issue of the journal Nature suggests that meat and dairy-heavy diets alter gut bacteria—and fast. "The change happens quickly. Within two days, the types of microbes thriving in the gut shuffle around," reports NPR. "And there are signs that some of these shifts might not be so good for your gut: One type of bacterium that flourishes under the meat-rich diet has been linked to inflammation and intestinal diseases in mice."
It's not the first study to look at gut bacteria and diet, but what makes this research unique is the focus on a shorter time span, according to NPR. "Previous research in this field had turned up tantalizing evidence that eating fiber can alter the composition of gut bacteria. But these studies had looked at diets over long periods of times." These researchers truncated that significantly to just a few days. They wanted to know whether or not the presence or absence of fiber "could alter gut bacteria more rapidly."
The microbiome, the bacteria that colonize the digestive tract—is heavily influenced by what we feed it. Science is discovering that these invisible house guests play a far more important role in our health, body weight, immune function, and even our moods and behavior. And the researchers found that the subjects of this study experienced a dramatic shift in gut bacteria in just a few days. The subjects spent several days eating mostly meat and dairy products before shifting to several days of fiber-rich plant-based diets. "The relative abundance of various bacteria species looked like it shifted within a day after the food hit the gut," researcher Lawrence David told NPR. The behavior of the gut bacteria began to change. "The kind of genes turned on in the microbes changed in both diets," he says.
"In particular, microbes that "love bile" — the Bilophila — started to dominate the volunteers' guts during the animal-based diet," reports NPR. "Bile helps the stomach digest fats. So people make more bile when their diet is rich in meat and dairy fats." And according to the researchers, Bilophila promotes inflammation in the body. Inflammation is a precursor to a number of ailments including arthritis, heart disease and high cholesterol.
"Our study is a proof of concept that you can modify the microbiome through diet," David says. "But we're still a long ways off from being able to manipulate the community in any kind of way that an engineer would be pleased about."
Keep in touch with Jill on Twitter @jillettinger
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