Taipei, Apr 5 (IANS): The microbial composition of the gut may affect a child's susceptibility to attention-deficit/hyperactivity disorder (ADHD), according to a study.

ADHD is one of the most common neurodevelopmental disorders of childhood.

Children with ADHD may have trouble paying attention, controlling impulsive behaviours (may act without thinking about what the result will be), or be overly active.

To understand the link between ADHD and gut microbiota, a team of researchers from Taiwan compared faecal samples from 35 children with ADHD and 35 healthy controls.

The human gastrointestinal tract hosts a large population of microorganisms such as bacteria, viruses, and fungi.

The results published in the Journal of Child Psychology and Psychiatry showed that samples from children with ADHD had higher levels of certain species of fungi and lower levels of other species.

"The human body is home to a complex and diverse microbial ecosystem, and findings from this study suggest that dysbiosis of the fungal mycobiome in ADHD can influence patient health," said the team including Lian-Jen Wang, child psychiatrist at Kaohsiung Chang Gung Memorial Hospital, Taiwan.

Dysbiosis is often defined as an "imbalance" in the gut microbial community that is associated with disease.

In experiments with cells grown in the lab, one species in abundance in samples from children with ADHD -- called Candida albicans -- increased the permeability of cells that line the intestine.

This could create a "leaky gut" that allows bacteria into the bloodstream, possibly resulting in inflammation throughout the body and brain.

The study also showed that abundance of Candida was found much higher among males with ADHD than without the disorder. No such differences were observed among females with and without ADHD.

"As ADHD is a male predominant disease, whether microbiome dysbiosis is involved in sex specific manifestation of ADHD warrants further investigations," the authors noted.