Speaker 1: Welcome to brain Stuff from how stuffworks dot com. Where
Speaker 1: smart happens him Marshall Brain, What is happening when we fart?
Speaker 1: We all suffer from this problem to varying degrees. Where
Speaker 1: does the gas come from? Just think about your digestive
Speaker 1: system for a moment. One thing that's obvious is that
Speaker 1: digestion involves breaking things down. Everything in food has to
Speaker 1: be broken down into small units in order to enter
Speaker 1: the bloodstream. Protein must be broken down into its individual
Speaker 1: amino acids, Fats must be broken down into fatty acids,
Speaker 1: and carbohydrates both simple and complex must be broken into
Speaker 1: individual glucose molecules. Flatulence occurs when a food does not
Speaker 1: break down completely in the stomach and the small intestine.
Speaker 1: As a result, the food makes it to the large
Speaker 1: intestine in an undigestested state. For example, if you are
Speaker 1: lactose intolerant, it means that you lack an enzyme lac
Speaker 1: taste in your intestine. This enzyme breaks lactose apart into
Speaker 1: two sugar molecules so they can enter the bloodstream without lactaste.
Speaker 1: Lactose passes undigested through the stomach and small intestine, and
Speaker 1: it arrives in the large intestine. They're the lactose meets
Speaker 1: up with billions of hungry bacteria, the natural intestinal fauna
Speaker 1: we all have in our large intestine. These bacteria are
Speaker 1: happy to digest lactose. They produce a variety of gases
Speaker 1: in much the same way that yeast produces carbon dioxide
Speaker 1: to leaven bread. Gases such as methane, hydrogen, and hydrogen
Speaker 1: sulfide are common gases that these bacteria produce. Hydrogen sulfide
Speaker 1: is the source of the odor we associate with flatulence.
Speaker 1: Certain foods per do more flatulence than others because they
Speaker 1: contain more undigestible carbohydrates than others. Beans, as you might expect,
Speaker 1: are particularly well endowed in this regard. Be sure to
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