The average American lies about 11 times a week, but next time you're tempted to tell a fib, remember this: lying won't just make you untrustworthy, new research finds it's also bad for your health.

In a small study, researchers at the University of Notre Dame discovered those who went out of their way to avoid telling untruths for 10 weeks were less anxious, had better relationships and tended to sleep better.

And it wasn't just blatant lies that took their toll. The researchers also found that people who told little "white lies" or who withheld information -- commonly known as lies by omission -- also experienced additional stress.

"Not violating others' expectation of honesty is likely to build trust, which may be key to good health through improving our relationships," said researcher Anita Kelly, PhD, a professor of psychology at the University of Notre Dame.

Sally Theran, PhD, assistant professor of psychology at Wellesley College in Wellesley, MA, whose own research produced similar findings, added, "When we lie, it adversely affects our self-esteem and increases our sense of shame. So, it's not surprising at all that ... telling the truth was related to all these positive outcomes."

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