Getting dirty could help mental health

Published on 02/04/2007 00:47

PEOPLE who suffer from depression could benefit from getting "dirty", according to new research published today.

A "friendly" bacteria found in soil has the same uplifting effects as those produced by anti-depressant drugs, the study found.

A study of mice found they altered their behaviour and appeared more relaxed after they were treated with the Mycobacterium vaccae bacteria.

Scientists at Bristol University and University College London found the bacteria stimulated the immune system and activated a group of neurons in the brain which produce the mood-enhancing chemical seratonin, a lack of which has been linked to depression.

Dr Chris Lowry, of Bristol University, the lead author on the paper, said: "These studies help us understand how the body communicates with the brain and why a healthy immune system is important for maintaining mental health.

"They also leave us wondering if we shouldn't all spend more time playing in the dirt. This soil that carries the bacteria is found almost anywhere.

"But we now need to find a way of getting it in our system, which we haven't done yet."

The study appears to support the "hygiene hypothesis" which argues that a rise in conditions such as asthma and allergies could be linked to a lack of exposure to various micro-organisms.

The emphasis on cleaning and hygiene, particularly in urban western environments, could be adversely affecting people's immune systems, according to the theory.

The findings, published in the journal Neuroscience, support the idea that increasing the release of seratonin in parts of the brain regulates mood.

Further studies are now planned to see if the bacteria stimulates this process.