Why food that make you fart are a good thing

Although renowned for creating delight in children, farts are not considered the best way to make friends and influence people.

But there is an upside: the production of gas means that your body is hosting the right kinds of bacteria.

To encourage these ‘good’ bugs – known as our microbiome – we need to eat fibre.

“Fermentable components of dietary fibre have a critical role in feeding the gut microbiome,” said Dr Trevor Lockett, Head of the Gut Health and Nutrition Group at CSIRO Food and Nutrition.

“This part of fibre is fermented mostly to short chain fatty acids, a process which creates gas.”

Fermentation is a chemical process that breaks down carbohydrates in fibre: bacteria do it in our bowels to create food for themselves. Molecules that improve the health of their host – that’s you – are also produced.

Dr Lockett presented an update on his group’s latest research at ‘Bugs, Bowels and Beyond’, the 2015 National Scientific Conference of the Australian Society for Medical Research held in Adelaide, South Australia this week.

He focused in particular on recent findings describing how different dietary components influence the microbiome, and determine their production of not just gas, but also molecules that are beneficial in the large intestine.

“For example, we know now that bacteria living in the large intestine produce a short chain fatty acid known as butyrate, which can reduce inflammation by stimulating regulatory immune cells,” he said.

“We’re now seeking to expand some of this work to see if we can improve inflammatory bowel disease.”

The component in food that manages to make it through digestive processes in the stomach and small intestine to feed the microbiome in the large intestine is known as resistant starch.

You can improve the proportion of resistant starch in your diet by eating unrefined whole grains, pulses and legumes, unripe bananas and cooked and cooled foods such as potatoes, pasta and rice.

Dr Lockett explained that in addition to conducting fundamental research, scientists at the CSIRO work across the fields of nutrition and agriculture for product development.

“As our understanding of the beneficial components of dietary fibre has improved, we’ve been able to inform colleagues who are growing grains for cereal purposes,” he explained.

“If we can include and enrich resistant starch in marketable grains, perhaps we can drive health benefits.”

Dr Lockett’s CSIRO colleague Dr Bianca Benassi-Evans – who is based in the South Australian Health and Medical Research Institute (SAHMRI) building – has recently trialed two non-genetically modified barley grains to determine their impact on bowel health.

Comparing the two candidate CSIRO barley grains against regular barley and puffed rice as breakfast meals in a sample of 20 adults, she found both to have desirable features.

“Our grains increased the acidity in stool samples, and increased bowel production of butyrate, a short chain fatty acid,” she said.

“Both of these outcomes are biomarkers of good bowel health.”

Additional studies are currently taking place, through which Dr Benassi-Evans hopes these grains may end up in your cereal aisle.

“What you choose in that supermarket can have dramatic effects on gut health,” she said.

Which breakfast products make you fart is a question you’ll have to determine yourself.

Which foods make you windy? Do you dare to share? 

CSIRO Food and Nutrition in South Australia has laboratories and clinical consulting facilities at SAHMRI and The University of Adelaide.