Studies Show Intestinal Bacteria Linked to Obesity

New studies conducted by Dr. Jeffrey I. Gordon of Washington University in St. Louis, show that bacteria in the gut play a key role in a persons propensity to gain weight, and that changes in diet trigger an immediate and explosive change in the bacterial balance in the intestines. A high sugar, high fat diet not only adds calories, but changes the bacterial balance in the intestines, making it easier to gain weight and harder to loose it.

The two major types of bacteria in the gut are Firmicutes and the Bacteroidetes. To determine the effects of the two bacteria, two groups of mice were given very different types of diets. One group was put on a diet high in sugars and fats, the second group was fed plant based, low fat food. Results showed the mice on the low fat diet had higher levels of Bacteroidetes, and stayed lean, while mice consuming the fat heavy diet had higher levels of Firmicutes, and began to gain weight. It is as yet unclear whether these levels actually caused weight gain or are the result of it, but doctors now have a new tool for determining who is at risk for obesity.