Our genes influence whether we are fat or thin by shaping which types of microbes thrive in our gut, scientists are now suggesting.

A recent discovery is pointing towards healthy bacteria one day being used to treat obesity and by studying human twins, scientists have found a type of bacteria that was not only associated with being thin but also seemed to run in families.

When the researchers treated mice with a specific member of this bacterial family, isolated from the twin study, the animals gained less weight than mice that did not get this treatment.

They are now working to identify which genes seem to influence the presence of the bacteria and why it would have an effect on weight and hope to be able develop these findings to create a probiotic to regulate weight.