The research came when human twins were studied.
One of each set of twins was obese and the other thin. Doctors took the gut bacteria from each of the twins and placed it in mice that had been raised free of microbes.
The mice receiving the fat twin’s bacteria gained substantial weight while the mice with the thin bacteria did not.
More importantly, when the bacteria from the thin twin was placed in the obese mice, they lost weight.
Scientists called the findings "weird and wonderful" but stop short of saying it will be a cure for obesity.
Some researchers favor attempting to replicate the bacteria and then turning it in a pill but they warn great caution must be taken.
The New York Times reports getting the correct combination of bacteria for each person is vital.
In previous looks at using bacteria helping to prevent aging doctors found it could have an impact on personality and mood.