High-fat diet can alter behaviour and produce signs of brain inflammation, according to a new study.
High-fat diets have long been known to increase the risk for medical problems, including heart disease and stroke, but there is growing concern that diets high in fat might also increase the risk for depression and other psychiatric disorders, researchers said.
Researchers at the Louisiana State University said the new study raises the possibility that a high-fat diet produces changes in health and behaviour, in part, by changing the mix of bacteria in the gut, also known as the gut microbiome.
Researchers tested whether an obesity-related microbiome alters behaviour and cognition even in the absence of obesity.
Non-obese adult mice were conventionally housed and maintained on a normal diet, but received a transplant of gut microbiota from donor mice that had been fed either a high-fat diet or control diet.
The recipient mice were then evaluated for changes in behaviour and cognition.
The animals who received the microbiota shaped by a high-fat diet showed multiple disruptions in behaviour, including increased anxiety, impaired memory, and repetitive behaviours.
Further, they showed many detrimental effects in the body, including increased intestinal permeability and markers of inflammation. Signs of inflammation in the brain were also evident and may have contributed to the behavioural changes.
"This paper suggests that high-fat diets impair brain health, in part, by disrupting the symbiotic relationship between humans and the microorganisms that occupy our gastrointestinal tracks," said Dr John Krystal, Editor of the journal Biological Psychiatry in which the study was published.
Further research is necessary, but the findings suggest that the gut microbiome has the eventual potential to serve as a therapeutic target for neuropsychiatric disorders, researchers said.
