Asthma inhaler
Including more fibre rich foods into the diet can help protect against allergic asthma, a new study reveals.forestfolks/Flickr

Including more fibre rich foods into the diet can help protect against allergic asthma, a new study reveals.

A team of researchers from Switzerland reached the conclusion after conducting experiments on mice.  Benjamin Marsland from the University Hospital of Lausanne and colleagues found that eating a diet high in fibre, mainly by including more fruits and vegetables, helped immune system positively, altered balance of microbes in the gut, and influenced the risk of developing an inflammation in the airways, NewScientist reported. 

Asthma is the inflammation of the air passages, leading to narrow the airways that carry air from mouth and nose to the lungs. Tobacco smoke, dust mites, air pollution, furry pets, cockroach droppings, cold, allergies, exposure to chemicals are some of the common factors that trigger asthma.

For the study, the researchers exposed two sets of rodents to house dust mite extracts and found that animals receiving a fibre rich diet achieved considerable reduction in the number of immune cells linked to asthmatic inflammation than those who ate a diet below 0.3 per cent fibre.

On sequencing the DNA in the mice's faeces, researchers identified high levels of a bacteria that help convert fibre into the metabolites short-chain fatty acids (SCFAs).  The animals also had high levels of these metabolites in their blood. To re-confirm their theory, Marsland fed the metabolites to a third group of mice. Interestingly, the animals showed considerable reduction in the allergic inflammation response to dust mite extract and created immune cells that were less capable of prompting inflammatory responses in airways.

"We have shown that changing dietary fibre intake affects the development of immune-cell precursors in the bone marrow, which then go on to have effects in the lung,"  Marsland told NewScientist.

"From a simple dietary intervention perspective, when we think about what the components of a balanced and healthy diet are, having higher amounts of fermentable fibre could be important," he added later.

 The study has been published in the journal Nature Medicine.