By Stacey Leasca
Fingers Crossed Behind Back Lying
Credit: Cirilopoeta/Getty Images

Think about the last time you lied. You probably don't have to think very hard because the average human lies 1.65 times per day. That means every single day you tell a fib. Big or small. It does not matter. You do it, I do it, your spouse, your boss, your kids, and even your sweet mother does it. But why? Here are three scientifically-backed reasons why we're all a little dishonest, which we swear are all the truth.

We lie to protect ourselves

Psychology Today explained, often times people tell lies that are self-serving. These lies could be to save face, to avoid getting in trouble at work or at home, or could just be to make themselves look better. Psychologist Bella DePaulo further proved this theory by asking 147 participants to keep a diary of all their lies over the course of one week. In the end, she found that people lied an average of one to two times a day. And most of those lies were told to "hide inadequacies," Psychology Today reported.

We lie to protect others

Not all our lies are meant to be selfish ones. Think about every single time someone asked you, "do these pants make me look fat?" How many times did you tell the truth?

We do this, Psychology Today said, as part of a "kindhearted lie" which is "told with the intent of making another person look better or feel better, or to spare them from embarrassment, punishment, or blame, or from getting their feelings hurt."

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We lie to gain power

"Lying is so easy compared to other ways of gaining power," Sissela Bok, an ethicist at Harvard University, shared with National Geographic. "It's much easier to lie in order to get somebody's money or wealth than to hit them over the head or rob a bank."

As National Geographic further explained, researchers believe our ability to lie started in the caveman era. It started as a way to manipulate others, just as it is today. This way, early humans didn't need to resort to physical violence to get what they wanted.

While some lies may seem OK to tell, if you really want to catch a liar in the act, Psychology Today said there are a few tells to look out for: Changes in vocal pitch; Unusual blinking or fidgeting; The use of fewer first-person words; Difficulty making eye contact when speaking, or shifty eyes; The use of self-soothing techniques such as ear tugging, neck touching, collar pulling, or mouth covering; Inconsistent gestures or facial expressions that contrast with message content.