Welcome to brain Stuff from how stuffworks dot com. Where smart happens him Marshall Brain, What is happening when we fart? We all suffer from this problem to varying degrees. Where does the gas come from? Just think about your digestive system for a moment. One thing that's obvious is that digestion involves breaking things down. Everything in food has to be broken down into small units in order to enter
the bloodstream. Protein must be broken down into its individual amino acids, Fats must be broken down into fatty acids, and carbohydrates both simple and complex must be broken into individual glucose molecules. Flatulence occurs when a food does not break down completely in the stomach and the small intestine. As a result, the food makes it to the large intestine in an undigestested state. For example, if you are lactose intolerant, it means that you lack an enzyme lac
taste in your intestine. This enzyme breaks lactose apart into two sugar molecules so they can enter the bloodstream without lactaste. Lactose passes undigested through the stomach and small intestine, and it arrives in the large intestine. They're the lactose meets up with billions of hungry bacteria, the natural intestinal fauna we all have in our large intestine. These bacteria are happy to digest lactose. They produce a variety of gases in much the same way that yeast produces carbon dioxide
to leaven bread. Gases such as methane, hydrogen, and hydrogen sulfide are common gases that these bacteria produce. Hydrogen sulfide is the source of the odor we associate with flatulence. Certain foods per do more flatulence than others because they contain more undigestible carbohydrates than others. Beans, as you might expect, are particularly well endowed in this regard. Be sure to check out our new video podcast, Stuff from the Future. Join How Staff Work Staff as we explore the most
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