At Motherboard, we believe that honesty is the best policy. But if you really have to lie, you might want to do it on a full bladder.
A California State University study has shown that lies told by individuals who had to pee were more convincing. Student participants were quizzed on how they felt about certain social and moral issues. Afterward, half chugged 700 mL of water and the other half sipped a measly 50 mL. Forty-five minutes later, they were interviewed by a panel about their previously stated beliefs, having been told to lie about their opinions on two of the issues.
It turns out that the students who were feeling the call of nature showed fewer physical signs and gave more complex answers when they had to lie. The sample size of the study was small, at only 22 students, but the findings make sense—the focus on "holding it" might lead to increased focus in general.
Research leader Iris Blandón-Gitlin says that impulse control and bladder control have a surprising amount of neurological overlap. "They're subjectively different but in the brain they're not. They're not domain-specific. When you activate the inhibitory control network in one domain, the benefits spill over to other tasks." No pun intended.
In its writeup of Blandón-Gitlin's research, New Scientist cites David Cameron's habit of approaching important speeches with a full bladder, the politician having discovered long ago that it gives him increased focus and intensity. If the allegations recently leveled against him are true, he might want to start drinking.