WEBVTT - How Flatulence Works

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<v Speaker 1>Welcome to brain Stuff from how stuffworks dot com. Where

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<v Speaker 1>smart happens him Marshall Brain, What is happening when we fart?

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<v Speaker 1>We all suffer from this problem to varying degrees. Where

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<v Speaker 1>does the gas come from? Just think about your digestive

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<v Speaker 1>system for a moment. One thing that's obvious is that

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<v Speaker 1>digestion involves breaking things down. Everything in food has to

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<v Speaker 1>be broken down into small units in order to enter

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<v Speaker 1>the bloodstream. Protein must be broken down into its individual

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<v Speaker 1>amino acids, Fats must be broken down into fatty acids,

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<v Speaker 1>and carbohydrates both simple and complex must be broken into

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<v Speaker 1>individual glucose molecules. Flatulence occurs when a food does not

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<v Speaker 1>break down completely in the stomach and the small intestine.

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<v Speaker 1>As a result, the food makes it to the large

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<v Speaker 1>intestine in an undigestested state. For example, if you are

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<v Speaker 1>lactose intolerant, it means that you lack an enzyme lac

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<v Speaker 1>taste in your intestine. This enzyme breaks lactose apart into

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<v Speaker 1>two sugar molecules so they can enter the bloodstream without lactaste.

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<v Speaker 1>Lactose passes undigested through the stomach and small intestine, and

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<v Speaker 1>it arrives in the large intestine. They're the lactose meets

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<v Speaker 1>up with billions of hungry bacteria, the natural intestinal fauna

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<v Speaker 1>we all have in our large intestine. These bacteria are

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<v Speaker 1>happy to digest lactose. They produce a variety of gases

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<v Speaker 1>in much the same way that yeast produces carbon dioxide

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<v Speaker 1>to leaven bread. Gases such as methane, hydrogen, and hydrogen

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<v Speaker 1>sulfide are common gases that these bacteria produce. Hydrogen sulfide

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<v Speaker 1>is the source of the odor we associate with flatulence.

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<v Speaker 1>Certain foods per do more flatulence than others because they

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<v Speaker 1>contain more undigestible carbohydrates than others. Beans, as you might expect,

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<v Speaker 1>are particularly well endowed in this regard. Be sure to

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