Beans are high in soluble fiber, which is fermented by your gut bacteria, leading to increased gas production in the colon . Beans also contain a compound called raffinose.
The culprit is fiber. Beans are rich in dietary fiber, an insoluble carbohydrate . Although it is a carbohydrate, fiber is an oligosaccharide that your digestive tract doesn’t break down and use for energy, as it would simple sugars or starch .
Why do beans give us gas?
Beans cause gas because they contain a type of sugar , called oligosaccharide, that the body cannot break down. Gas can cause pain and discomfort, but there is a supplement you can take for relief. As long as it’s not causing pain or excessive bloating, gas is a normal part of the digestive process.
An answer is that beans, and other legumes like chickpeas, lentils and soybeans, are high in soluble fiber, which is considered beneficial for digestion. Unfortunately, it’s this soluble fiber that is also central to why they cause so much gas when you eat them.
This of course begs the inquiry “Why do beans make you gassy?”
Oligosaccharides in beans make it all the way to the large intestine undigested . Bacteria in the large intestine finally feed on these sugars. Doing so causes fermentation (a chemical breakdown) and the production of gas. We release that gas as flatulence.
To prevent gas that is caused by eating beans or other foods , the oligosaccharides must be broken down before they reach the large intestine and become food for the resident bacteria that live there. There is an enzyme that breaks down oligosaccharides, called alpha-galactosidase.
It is the bacteria in the intestine that finally breaks down these sugars . Doing so causes fermentation and the production of gas that we release as flatulence. By the same principle, other foods that come into the large intestine without being absorbed in the small intestine will cause gas.
An April 2016 study published in the Iranian Red Crescent Medical Journal lists beans, lentils, fried and fatty foods, sour and spicy foods, coffee, tea, cocoa, ice and cold beverages as some of the foods that are likely to give you a lot of gas.
Why can’t I Digest beans?
The reason why people have problems digesting beans is that we lack the alpha-galactosidase enzyme in our digestive tract. This enzyme breaks down indigestible oligosaccharides into smaller components so they can be digested. For many years, people have taken a product called Beano, which contains alpha-galactosidase to help prevent gas from beans.
Beans contain a complex sugar called raffinose that the body can’t fully digest. Normally, sugars like raffinose would be digested in the small intestine. However, since humans lack the enzyme to break it down, raffinose makes its way from the small into the large intestine still intact.
Do beans have insoluble fiber?
Although it is a carbohydrate, fiber is an oligosaccharide that your digestive tract doesn’t break down and use for energy, as it would simple sugars or starch. In the case of beans, insoluble fiber takes the form of three oligosaccharides : stachyose, raffinose, and verbascose. So, how does this lead to gas?