Whether it's a racy act from college days, a child's confession that you promised not to share with your spouse or the revelation of your best friend's affair, by midlife you're probably carrying around a number of secrets. But whether you realize it or not, they're getting heavier all the time, especially the juicy ones — and they could be threatening your health.
Neuroscientists now believe it's biologically better for us to confess our secrets, or better, just to refuse to be party to someone else's. The reason: holding on to them puts the brain in an awkward, compromised position. The cingulate cortex, essential to our emotional responses, is wired to tell the truth. This "logical lobe" signals other regions of the brain to share information so it can move on to more important functions, like learning. But when you keep a secret locked inside, you don't allow the cingulate to perform its natural functions. Instead, the cortex becomes stressed.
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When you choose to hold onto a secret, your brain's orbital prefrontal cortex simulates in your mind just how bad sharing the secret will be, imagining all the possible negative outcomes. "The prefrontal cortex is involved in decision-making, complex thought and deception," says neurosurgeon Gopal Chopra, chief executive of PINGMD, which provides an app to facilitate communication between doctors and patients. If the two regions are at cross-purposes, the end result is what Chopra calls "the complications of emotional burden."
In other words, if your prefrontal cortex wins the battle within your brain over keeping a secret, the pressure it causes in the cingulate cortex leads your body to ramp up production of stress hormones. This is known as the "fight or flight" response, often triggered when we feel anxiety or fear. If the reaction persists, it can have potentially serious consequences. Every time you think about a deeply held secret, stress hormones such as cortisol can surge, impacting your memory, blood pressure, gastrointestinal tract and metabolism. "Those hormones also include norepinephrine," Chopra says, "which affects parts of the brain where attention and responses are controlled."
The bigger the secret, or the riskier you perceive its protection, the more intense the conflict within your brain, resulting in higher anxiety and a more potent fight-or-flight effect.
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"Sleep may be disturbed, which could lead to emotional mood swings and a propensity to be ill-tempered or lose your cool," says Dr. Allen Towfigh, a neurologist and sleep medicine specialist at New York Presbyterian Hospital/Cornell Medical Center. "You may also have difficulty with memory and learning. And the excess release of cortisol will cause a host of other ailments, including possible increase or loss of appetite and disruption of metabolism."
Spiking cortisol levels have also been linked to a weakened immune system, osteoporosis, increased blood pressure and a loss of collagen in the skin, which can lead to deeper wrinkles and a loss of elasticity.
Should We Stop Keeping Secrets?
Despite the dangers, keeping secrets is part of human nature. "Even when there is risk involved in keeping a secret, we believe there is greater risk in its disclosure," says psychiatrist Peter Zafirides of Columbus, Ohio. "Simply, we decide that the disclosure of the secret will be more painful to us than keeping it hidden. So, it stays a secret."
Not all secrets bring us stress, Zafirides emphasizes. Some secrets are useful, even pleasant, like a child's gift or a spouse's surprise party. "As long as the secret isn't hurting you or anyone else, or isn't perceived by you as being a bad thing," he says, "keeping it doesn't have to be hazardous to your health."
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But if a friend offers to tell you something weighty in strictest confidence, think before you sign on. Ask yourself first if the information truly warrants privacy, Zafirides advises. "Analyze the reasons that you are keeping something secret and the consequences of disclosing it," he says.
It also helps to consider other people's likely reactions to discovering the secret you're protecting, whether it's your own or someone else's. Often, Zafirides says, those reactions are much less dramatic than we imagine. This especially applies to embarrassing stories from years ago. "Many people find the reasons we may keep some secrets earlier in life may not be as relevant as we get older," he says.
Finally, while it may sound like a trivial exercise, research has found that writing out the pros and cons of holding on to a secret that's causing you stress may be helpful. "There is no real physiologic explanation," Chopra says, but behavioral studies have shown that writing it out leads to dramatic reductions in stress hormone levels and blood pressure, and improvements in mental health.
Taking the time to consider the implications of locking away sensitive intel is ultimately a healthy exercise — and that's no secret.