Irish scientists have discovered a link between bowel bacteria and clinical depression, and fecal transplantation is emerging as the medical treatment of choice for the mood disorder.

The recipient of the screened transplant material can benefit from the billions of useful bacteria that occupies the lower digestive tract. Fecal transplants can help clear out antibiotic resistance and treat difficult infections involving bacteria, the Irish Times reports. The treatment may also help improve your mood.

Scientists at the Alimentary Pharmabiotic Centre Biosciences Institute at University College Cork have discovered that the mix of bacteria in the gut could have a direct effect on a person’s mood.

Prof Ted Dinan and Prof John Cryan at UCC decided to take these findings a step further and began to test whether depression can in some way be transmitted through gut bacteria.

Prof Ted Dinan told the Irish Times that brain function in humans was “very much dependent” on the products from the gut bacteria.

“There are fundamental differences in the microbiota of depressed and non-depressed people.”

The researchers tested their theory on rats.

The rats’ microbiota was cleared using antibiotics and then a fecal transplant was given from a human donor with clinical depression.

The rats began to show signs of depression and anxiety, and experienced weight loss and fatigue.

While the findings are only preliminary and it is too early to understand whether changing the mix of the bacteria in the gut might affect depression in humans, these early results should be of interest to clinicians who use human fecal transplants as a treatment.

Prof Dinan said that the research suggests that depression and other disorders could be transmitted in gut bacteria, which should taken into consideration when screening healthy donors in the future.