A simple daily soluble fibre supplement could help people with stable asthma control their symptoms, results of a first-in-human trial suggest.
The randomised placebo controlled three-way cross-over trial involving 17 people with asthma found a daily dose of the soluble fibre inulin reduced airway eosinophils and improved asthma control.
Speaking to the limbic lead author Professor Lisa Wood from the University of Newcastle’s Priority Research Centre for Healthy Lungs said her research group had spent several years looking at how a westernised diet might contribute to the worsening of asthma.
“Westernised diets are dominated by processed and fast foods which really turns healthy eating upside down,” she explained.
“Foods that should be consumed in small amounts dominate the diet and subsequently fruits, vegetables and wholegrains are consumed to a lesser amount…one of the consequences of that is low fibre intake.”
The first hint of a link between increased dietary fibre and reduced airways inflammation came from animal studies, Professor Wood said.
“But there was no human data so we started off with a cross sectional observational study in humans and saw an inverse correlation between fibre intake and airway inflammation and a positive correlation with lung function”.
It was these findings that gave the research group the motivation to conduct the current study, which tested three treatments: inulin, inulin and a probiotic, and placebo.
Results showed that after 7 days the most effective treatment was inulin on its own. Interestingly, according to Professor Wood the most striking finding was that the treatment was most effective in people who were poorly controlled at the start of the study, despite already using inhaled corticosteroids.
“All of these patients had an improvement in their asthma control and half had a clinically meaningful improvement in their asthma control,” she said.
“The fact that we can achieve such a change with dietary manipulation is really very exciting. We need to follow these findings up with a larger, longer-term trial,” she said.