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The Truth Is, Lying Makes You Sick

A new study proves lying leads to illness — and the truth will set you free

By Gina Roberts-Grey | March 15, 2013

We are a nation of liars. Americans tell an average of 11 lies, both big and small, each week. Most of us fib because we’re trying to sidestep something uncomfortable, says Fran Walfish, a family psychotherapist and author in Beverly Hills, Calif. "Very often, people lie so no one will be mad at them," she says. At other times, we fudge the truth to feel better about ourselves, impress someone, or escape punishment or other negative consequences.
 
The trouble, new research says, is that all this avoidance of the truth can be hazardous to our health.

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When people lie, they are more prone to feeling anxious or blue, and to experiencing frequent headaches, runny noses, bouts of diarrhea and back pain. When people change their ways and start telling the truth more often, however, they can improve both their mental and physical health, says University of Notre Dame psychology professor Anita Kelly, lead author of a new study on the effects of lying.

The Notre Dame study looked at 110 people, ranging in age from 18 to 71, over a period of 10 weeks. Half the participants agreed to try to stop telling lies (both major and minor) for the duration of the test. The other half received no special instructions. Subjects took weekly polygraph tests to assess the number and type of lies they had told in the previous week. "Those who were instructed to dramatically reduce lies experienced significantly better health than those in the group that continued to lie," Kelly says.

Her team found that participants who began telling the truth more often experienced 54 percent fewer mental health complaints (such as anxiety or feeling blue) over the course of the study, and 56 percent fewer physical health complaints (such as nausea or headaches). Subjects who began telling the truth more often also reported happier relationships and improved social interactions.

Surprisingly, the "size" of a lie doesn’t appear to have much impact on its health effects, Kelly says. Both minor lies, like telling a friend you can’t meet for coffee because you "have to work," and big lies, such as claiming false credentials in a job interview, can negatively affect your health. "Both white and major lies can be problematic," she says, "because they can both cause the person to be seen as a liar. Both can violate expectations of honesty in a relationship." And all of that leads to feelings of anxiety and guilt.
 
Why Lying Makes You Sick

Because you know it’s wrong to lie, doing so "goes against what you deem as 'right,' and builds anxiety," Walfish says. The anxiety just increases as you try to keep from being caught. "A person who lies doesn’t want to be found out. They want the whole thing to go away," she says.
 
"As a result of all that guilt, or related anxiety and stress, you begin to physically feel the effects of the lies," says Reef Karim, an assistant clinical professor of psychiatry at the UCLA Semel Institute for Neuroscience. "There's definitely a connection." Your immune system could become compromised because your body is stressed, making it harder to fight off colds and flus. "For some, it’s an immediate effect," Karim notes. "For others it’s a slow build of physical problems, like headaches."

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The level of guilt you feel about your lies is a crucial factor in how much they'll affect your body. "The more guilt or anxiety you feel," Karim says, "the more physical and mental symptoms you’re going to experience."
 
The Power of Telling the Truth 

Just as you try to eat well and get regular exercise to maintain your overall health, experts say, you need to develop the healthy habit of telling the truth. "People need to experience the feeling of freedom and strength derived from telling the truth in difficult situations," Walfish says. "Taking the leap of faith and telling the truth — regardless of the outcome — is a wonderful feeling of power. You feel you can handle anything."
 
Unburdening yourself of a lie by coming clean to family or friends also helps. "The relief of not carrying the burden of a lie can be significant," Karim says. "'Fessing up' can absolutely make a person feel better physically and mentally by opening the flood gates to release built-up guilt, stress and despair."

And that's the truth.