Why Beans Make You Fart

Beans, or legumes, are an incredibly nutritious, high fibre food but, whether we like to admit it or not, eating them can sometimes most times give us flatulence.

While some may get it worse than others, there is one main reason beans cause gas.

"Legumes contain unabsorbed short-chain carbohydrates called galacto-oligosaccharide (GOS) and fructans. These poorly absorbed sugars are rapidly fermented by gut bacteria in the large bowel, resulting in gas. Some people are more susceptible to the gas production than others," Charlene Grosse, accredited practising dietitian and spokesperson for Dietitians Association of Australia, told The Huffington Post Australia.

Although legumes contain these poorly absorbed sugars, they can actually promote good gut health.

"Research indicates this type of sugar found in legumes is healthy for your gut," Grosse said.

One popular theory as to why beans cause gas is the soapy liquid you find in canned beans.

"When legumes, for example red lentils, are boiled in water, the liquid they are cooking in becomes higher in oligosaccharides. This is because they are water soluble, meaning the sugar leaches out of the food and into the water," Grosse told HuffPost Australia.

To reduce the chance of flatulence, Grosse recommends properly preparing your legumes and to introduce them slowly into your diet.

Adding a lot of legumes in the diet in a short space of time may lead to gas. If you are not used to having legumes introduce them slowly over several weeks.

"Soaking and rinsing dry legumes before cooking can help lower their oligosaccharide content," Grosse said.

For legumes in a can, make sure to rinse them under water in a colander until the bubbles disappear.

"Canned, rinsed legumes have even lower levels of oligosaccharide than the dry, soaked and rinsed legumes."

"Adding a lot of legumes in the diet in a short space of time may lead to gas. If you are not used to having legumes, introduce them slowly over several weeks," Grosse told HuffPost Australia.

Flatulence after eating can also be indicative of a larger digestive problem, so it's important to monitor any unusual changes.

"When considering dietary triggers, it is important to note that different people are susceptible to different foods. Excessive flatulence can be due to a number of reasons including swallowing air, consumption of carbonated beverages, fibre intake, intestinal bacteria and fermentable short chain carbohydrates (FODMAPs)," Grosse said.

"Some digestive system disorders, such as irritable bowel syndrome, can produce a sensation of excessive flatus. See your doctor if you experience unusual flatulence, abdominal pain, changes to toilet habits or any other uncomfortable symptom associated with digestion."