Uncovering the relationship between gut bacteria and anxiety

An Australian-led study has discovered a certain genus of gut bacteria which could be linked to a child’s risk of developing anxiety.

The research, carried out between Deakin University, Barwon Health and the Murdoch Children’s Research Institute (MCRI), is the first to show children with a lower amount of prevotella at age one are more likely to show signs of anxious behaviours at age two.

Researchers examined data from 201 children in the Barwon Infant Study (BIS), analysing faeces samples at one, six and 12 months of age, before measuring behavioural outcomes at two years.

Findings revealed children with a lower level of prevotella in their stools had a higher prevalence of anxiety-like behaviours including shyness, sadness and an internal focus, an indicator they may be at higher risk of developing childhood anxiety.

Study leader Professor Peter Vuillermin said prevotella was more common in the stomachs of people living in non-Westernised environments.

He also said the study found less prevotella in children who had recently taken antibiotics.

“Growing evidence supports the idea that antibiotics, poor diet and other factors in the modern world are leading to the loss of our traditional gut bacteria, and in turn, health problems,” Professor Vuillermin said.

“There is intense interest in the relationship between gut bacteria and brain development, but most of the evidence has come from experiments in mice. This is one of the first human studies to compare the composition of baby’s gut bacteria to subsequent behavioural outcomes.”

The paper’s first author, Dr Amy Loughman from Deakin’s Food and Mood Centre, said the research team was looking to further its understanding of prevotella and its relationship to anxiety in the hope of bettering health outcomes.

“One day we could get to the point where we can look at a child’s poo at 12 months, and if they are showing levels of bacteria that put them into a high-risk category for anxiety, we can offer an early intervention,” Dr Loughman said.

“This might be a supplement of prevotella or other bacteria, or it could be in the form of behavioural and family support to bolster their psychosocial environment. But we need to get more research behind us before we can reach that point.”

Dr Loughman encouraged parents to follow Australian dietary guidelines and feed children a diet high in fibre and to work with their doctor to minimise the use of antibiotics.