Meat and Dairy Can Rapidly Alter Gut Bacteria and Cause Inflammation

Michelle Schoffro Cook     December 19, 2013

The adage “you are what you eat” might never have been truer. According to new research, your health may be determined by what you eat, and what microorganisms came along for the ride.

A new Harvard University study published in the journal Nature found that diet rapidly alters the microorganisms residing in the gut. And if what you ate was either meat or dairy, you might not be happy with their findings.  It has long been known that diet influences the type and activity of the trillions of microorganisms residing in the human gut, but Harvard scientists found that even what we eat in the short-term can have drastic effects on the type and numbers of microbes in our gut and their capacity to increase inflammation in the gastrointestinal tract (GI).

Researchers found that within two days of consuming an animal-based diet, microbes in the alistipes, bilophila, and bacteroides families increased.  Harvard scientists also discovered that microbes found in the food itself, including bacteria, fungi, and viruses, quickly colonized the gut.  And, perhaps most notably, they discovered that an animal-based diet caused the growth of microorganisms that are capable of triggering inflammatory bowel disease within only two days of eating these foods.  Earlier research showed that bilophilia overgrowth promotes inflammation.  Still further research has linked inflammation-causing microbes to serious chronic diseases, meaning that the Harvard study has potentially far-reaching implications for disease prevention and treatment.

The scientists put volunteers on a meat and cheese diet, then switched them to a fiber-rich, plant-based diet to track the effect on intestinal microbes.  They ate a breakfast of eggs and bacon, a lunch of ribs and briskets, and salami, prosciutto and assorted cheeses for dinner, along with pork rind snacks.  After a break from eating this diet the volunteers ate a plant-based diet of granola for breakfast, jasmine rice, cooked onions, tomatoes, squash, garlic, peas, and lentils for lunch and a similar dinner, with bananas and mangoes for snacks.

The scientists analyzed the volunteers’ microbes before, during, and after each meal.  The effects of the meat and cheese were immediate.  The abundance of bacteria shifted about a day after the food hit the gut. After three days on either diet, the bacteria in the gut changed their behavior.

Lead scientist Lawrence David, PhD admits that the meat and cheese diet was extreme; however, it seems to have painted a clear picture of the outcome of a diet heavy in meat and cheese—a typical diet for many people who use high protein diets to lose weight.  Dr. David said in an interview with NPR “I love meat … but I will say that I definitely feel a lot more guilty ordering a hamburger … since doing this work.”  He also indicates that the study unlocks a potentially new avenue for treating intestinal disease.  I would add that it likely unlocks ways to treat other inflammatory diseases in the body. Heart disease, diabetes, arthritis, and even cancer have been linked to inflammation in the body.

You may want to rethink that bacon-wrapped sausage hors d’oeuvre or cheese platter during the holidays … or anytime.

source: Care2.com