What happens when you suck at a straw while having a drink?

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December 31, 2012 11:46AM

You lower the pressure inside your mouth and the atmosphere pushes the liquid up the straw. That is why it is almost impossible to suck the liquid into your stomach directly. You can't lower your stomach pressure much. The mouth has muscles to create a small lower pressure area, then you gulp the contents that wind up in the mouth.