Typical College Student Diet Food Derived Microorganisms and Their Relation to the Human Gastrointestinal Microflora

Abstract

Current research in the field of obesity has shown that obese people generally have a higher percentage of Firmicutes compared to Bacteroidetes in their gastrointestinal tracts than lean people. The goal of this study was to assess whether or not different foods contain unique bacterial profiles and if there is a correlation between foods and the types of bacteria that may be present. This study was based on diets that are typically consumed by college students. Six meals, two breakfasts, two lunches, and two dinners were created based off a class project that detailed the diet of Texas A&M University students. These meals consisted of a banana, cereal, and orange juice; a bagel, breakfast burrito and coffee; a turkey sub sandwich, chips and a soda; macaroni and cheese, carrots and water; pepperoni pizza, salad and water; and finally a cheeseburger, fries and a soda. All the foods were purchased either on campus dining halls, or stores and fast food restaurants in College Station, Texas. Portions of the food samples were plated on Tryptic Soy Agar media and Brucella Blood Agar to determine the aerobic and anaerobic bacterial loads respectively. The total microbioial communities were extracted from defined amounts of the different food samples and the 16s rRNA genetic diversity were analyzed pyrosequencing. It was found that each food does have a unique bacterial profile. There was, however, no correlation between the nutritional content of the foods and presence of specific bacterial groups. It was determined that on an average, a college student will consume via foods a minimum of about 6.38x1010 bacterial sequences of bacteria each year, and about 2.55x1011 sequences of bacteria during an average 4-year college career. The data implies that foods contribute not only nutrients to the human body but can also be a major source for the introduction of microbial populations into the gastrointestinal tract. Since alterations in the gastrointestinal populations do alter host-microbiota interactions which in turn affect metabolic syndromes, this study illustrates one pathway through which microbial populations are adding to the diversity within the gastrointestinal system.