Happiness Comes From Your Gut

Scientists have shown that serotonin, a chemical that plays an integral part in mood, stress, and anxiety, is linked to amount of bacteria in one's gut early in life. The findings could open up new pathways for treating depression.

The team of researchers bred germ free mice and recorded their serotonin levels in adulthood. Then, they introduced bacteria into the mouse's gut, but found no neurological changes or elevated serotonin. This indicates that the effects of gut bacteria early in life are irreversible. They also found that the bacteria played a larger role in serotonin levels in males than females.

"As a neuroscientist these findings are fascinating as they highlight the important role that gut bacteria play in the bidirectional communication between the gut and the brain, and opens up the intriguing opportunity of developing unique microbial-based strategies for treatment for brain disorders," said Professor John F. Cryan, senior author on the publication and Head of the Department of Anatomy & Neuroscience at UCC.

Previous research carried out by Dr Gerard Clarke, Professor Fergus Shanahan, Professor Ted Dinan and Professor John F Cryan and colleagues at the Alimentary Pharmabiotic Centre in UCC showed that a connection exists between bacteria in the gut and the brain. This relationship affects normal health and brain behavior.

The researchers hope that by understanding the complex set of relationships that help determine overall mood and happiness, treatments for depression and other psychological problems can be improved.