In this small study, 8 women and 1 man ages 50-65 were provided with foods that fit the Mediterranean diet profile: high fiber, whole grains, dry beans/lentils, olive oil, and 5 servings of fruits/vegetables a day. After 2 weeks, they provided blood for the analysis of fasting lipids and stool samples to determine the microbes present.
The results indicated a decrease in total cholesterol and LDL cholesterol levels. In addition, there was clustering of individuals' microbial profiles.
"What we expected to find was that a particular microbe species increased, but we haven't observed that," said Steinle. "Instead, each individual appears to have a unique microbiome signature, like a fingerprint. A sample from 5 people would result in 5 unique profiles. It's the first time we've observed that this signature remained true, even after manipulation of diet," Steinle added.
This study adds another clue to the complicated nature of the gut microbiome. Dr. Steinle will present the data for the American Society for Nutrition's poster sessions on Tuesday, April 23. Prior to the poster session on the microbiome on April 23, there is a symposium "Managing the Microbiome in Human Gastrointestinal Disease" on Saturday, April 20, 8-10 am.