How Lying Affects Your Health

To tell the truth, honesty may be the best policy, for physical and mental reasons.

A business woman crossing her fingers behind her back.
By SHARE

One little white lie here. Another there. Liar, liar—no, your pants aren't going to catch on fire. So what could it hurt? Plenty, say researchers, and a new study suggests that honesty may indeed be the best policy, for both your health and well-being. Listen up, because most of us tell 11 lies a week, or one or two each day. And all that fibbing could lead to headaches, sore throats, and feeling sad and stressed.

Anita Kelly, a psychology professor at the University of Notre Dame in Indiana, spent 10 weeks tracking the health of 110 adults. She asked half of them to stop lying throughout the study period—which meant no false statements, though participants could still omit the truth, keep secrets, and dodge questions they didn't want to answer. The other folks weren't given any specific instructions about lying, though they knew they'd be reporting the number of fibs they told each week. In addition to taking a weekly lie-detector test, participants filled out questionnaires about their physical and mental health, as well as the quality of their relationships.

[See How Your Personality Affects Your Health]

The results? Both groups lied less, but those instructed to tell the truth reaped more health improvements. "We established very clearly that purposefully trying not to lie caused people to tell fewer lies," Kelly says. "When they told more lies, their health went down. And when they told the truth, it improved." In fact, telling three fewer minor lies a week translated to four fewer mental health complaints, and three fewer physical complaints. (Those in the control group who independently told fewer lies logged around two fewer health complaints each week.) Kelly speculates that's because telling the truth improves relationships, as the study participants reported. And research has long indicated that people with good relationships have better physical and mental health.

Still, there could be more to it than the relationship factor, experts contend. Research on how lying affects health is scant, but lying is thought to trigger the release of stress hormones, increasing heart rate and blood pressure. Stress reduces your body's number of infection-fighting white blood cells, and over the years, could contribute to lower-back pain, tension headaches, a rapid heartbeat, menstrual problems, and even infertility. You've probably experienced the visceral effects of lying at least once. Imagine, for example, that you're planning on lying to your boss or girlfriend tomorrow morning. "I would bet that you can feel the tension in your shoulders, in your stomach, and in other parts of your body," says Linda Stroh, a professor emeritus of organizational behavior at Loyola University in Chicago and author of Trust Rules: How to Tell the Good Guys From the Bad Guys. "You would spend a lot of time planning the lie, executing it, and maintaining it."

[See 3 Ways to Help Good Kids Make Tough Choices]

And that can be awfully draining. "It takes a lot of negative physical and mental energy to maintain a lie," Stroh says. "We have to think before we answer and we have to plan what we say and do, rather than saying and doing what comes more naturally. We waste a lot of precious time covering our tracks rather than spending that time in positive ways, doing good things."

But is giving up lies cold turkey realistic? Not necessarily, and it's certainly not easy, Kelly says. Most study participants were able to cut back to one lie a week. Especially tricky: squeezing those seemingly innocuous little white lies out of our daily lives.

At the end of the 10-week study period, Kelly asked participants to reflect on how they had managed to curb dishonest tendencies. "We didn't find that anyone was using the study to give people a piece of their mind or tell them brutal truths," she says. "They just stopped exaggerating their day-to-day accomplishments, dropped excuses that weren't true, and told partial truths instead." For example: If a participant's girlfriend changed her hairstyle and he didn't like it, he couldn't lie and say that he did. But he could vaguely tell her: "I really like the way your face looks right now."