New research suggests brain inflammation to be reduced by foods high in fibre.
According to a new study from the University of Illinois, dietary fibre may be the much needed remedy to reduce brain inflammation.
Are fibre foods the new brain food?
As humans age, immune cells in the brain known as microglia become chronically inflamed. In this state, they produce chemicals known to damage cognitive and motor function.
Dietary fibre promotes the growth of good bacteria in the gut. When these bacteria digest fibre, they produce short-chain-fatty-acids (SCFAs), including butyrate, as by-products.
“Butyrate is of interest because it has been shown to have anti-inflammatory properties on microglia and improve memory in mice when administered pharmacologically,” says Rodney Johnson, professor and head of the department of animal sciences at University of Illinois, USA, and corresponding author on the Frontiers in Immunology study.
This new study reveals, in old mice, that butyrate inhibits production of damaging chemicals by inflamed microglia. One of those chemicals being associated with Alzheimer’s disease in humans.
Understanding how sodium butyrate works is a step forward, but the researchers were more interested in knowing whether the same effects could be obtained simply by feeding the mice more fibre.
“People are not likely to consume sodium butyrate directly, due to its noxious odour.” Johnson says.
“A practical way to get elevated butyrate is to consume a diet high in soluble fibre.”
Butyrate derived from dietary fibre should have the same benefits in the brain as the drug form, however no one has tested it before.
What were the steps of examination?
The next step was looking at signs of inflammation in the brain. The researchers examined about 50 unique genes in microglia and found the high-fibre diet reduced the inflammatory profile in aged animals.
Cognition, behaviour or the precise mechanisms in the gut-brain axis, was not examined, however researchers plan to tackle those aspects in the future as part of a new, almost $2 million grant from the National Institute on Ageing, part of the National Institutes of Health.
Although the study was conducted on mice, Johnson is comfortable extending his findings to humans participants.
“What you eat matters. We know that older adults consume 40 percent less dietary fibre than is recommended.”
Johnson concludes: “Not getting enough fibre could have negative consequences for things you don’t even think about, such as connections to brain health and inflammation in general.”