I have a confession to make.
But first, I want you to makea little confession to me.
In the past year, I want you to just raise your hand if you've experiencedrelatively little stress.
Anyone? How about a moderate amount of stress? Who has experienced a lot of stress? Yeah.
But that is not my confession.
My confession is this: I am a health psychologist, and my mission is to help peoplebe happier and healthier.
But I fear that somethingI've been teaching for the last 10 yearsis doing more harm than good, and it has to do with stress.
For years I've been telling people, stress makes you sick.
It increases the risk of everythingfrom the common cold to cardiovascular disease.
Basically, I've turned stressinto the enemy.
But I have changed my mind about stress, and today, I want to change yours.
Let me start with the studythat made me rethink my whole approach to stress.
This study tracked 30, 000 adultsin the United States for eight years, and they started by asking people, “How much stress have youexperienced in the last year?” They also asked, “Do you believe that stressis harmful for your health?” And then they used public death recordsto find out who died.
Some bad news first.
People who experienced a lot of stressin the previous year had a 43 percent increased risk of dying.
But that was only true for the people who also believed that stressis harmful for your health.
(Laughter) People who experienced a lot of stress but did not view stress as harmful were no more likely to die.
In fact, they had the lowest risk of dying of anyone in the study, including peoplewho had relatively little stress.
Now the researchers estimatedthat over the eight years they were tracking deaths, 182, 000 Americans died prematurely, not from stress, but from the beliefthat stress is bad for you.
(Laughter) That is over 20, 000 deaths a year.
Now, if that estimate is correct, that would makebelieving stress is bad for you the 15th largest cause of deathin the United States last year, killing more people than skin cancer, HIV/AIDS and homicide.
(Laughter) You can see why this study freaked me out.
Here I've been spendingso much energy telling people stress is bad for your health.
So this study got me wondering: Can changing how you thinkabout stress make you healthier? And here the science says yes.
When you change your mind about stress, you can changeyour body's response to stress.
Now to explain how this works, I want you all to pretendthat you are participants in a study designed to stress you out.
It's called the social stress test.
You come into the laboratory, and you're told you have to give a five-minute impromptu speechon your personal weaknesses to a panel of expert evaluatorssitting right in front of you, and to make sure you feel the pressure, there are bright lightsand a camera in your face, kind of like this.
(Laughter) And the evaluators have been trained to give you discouraging, non-verbal feedback, like this.
(Exhales) (Laughter) Now that you're sufficiently demoralized, time for part two: a math test.
And unbeknownst to you, the experimenter has been trainedto harass you during it.
Now we're going to all do this together.
It's going to be fun.
(Laughter) I want you all to count backwards from 996 in increments of seven.
You're going to do this out loud, as fast as you can, starting with 996.
Go! (Audience counting) Go faster.
You're going too slow.
(Audience counting) Stop.
Stop, stop, stop.
That guy made a mistake.
We are going to have to startall over again.
(Laughter) You're not very good at this, are you? Okay, so you get the idea.
If you were actually in this study, you'd probably be a little stressed out.
Your heart might be pounding, you might be breathing faster, maybe breaking out into a sweat.
And normally, we interpretthese physical changes as anxiety or signs that we aren't copingvery well with the pressure.
But what if you viewed them instead as signs that your body was energized, was preparing you to meet this challenge? Now that is exactlywhat participants were told in a study conductedat Harvard University.
Before they wentthrough the social stress test, they were taught to rethinktheir stress response as helpful.
That pounding heartis preparing you for action.
If you're breathing faster, it's no problem.
It's getting more oxygen to your brain.
And participants who learned to viewthe stress response as helpful for their performance, well, they were less stressed out, less anxious, more confident, but the most fascinating finding to me was how their physicalstress response changed.
Now, in a typical stress response, your heart rate goes up, and your blood vesselsconstrict like this.
And this is one of the reasonsthat chronic stress is sometimes associatedwith cardiovascular disease.
It's not really healthy to bein this state all the time.
But in the study, when participants viewedtheir stress response as helpful, their blood vesselsstayed relaxed like this.
Their heart was still pounding, but this is a much healthiercardiovascular profile.
It actually looks a lot like what happens in moments of joy and courage.
Over a lifetime of stressful experiences, this one biological change could be the difference between a stress-inducedheart attack at age 50 and living well into your 90s.
And this is really what the newscience of stress reveals, that how you think about stress matters.
So my goal as a healthpsychologist has changed.
I no longer wantto get rid of your stress.
I want to make you better at stress.
And we just did a little intervention.
If you raised your hand and said you'd had a lot of stressin the last year, we could have saved your life, because hopefully the next timeyour heart is pounding from stress, you're going to remember this talk and you're going to think to yourself, this is my body helping merise to this challenge.
And when you view stress in that way, your body believes you, and your stress responsebecomes healthier.
Now I said I have over a decadeof demonizing stress to redeem myself from, so we are going to doone more intervention.
I want to tell you about one of the most under-appreciatedaspects of the stress response, and the idea is this: Stress makes you social.
To understand this side of stress, we need to talk about a hormone, oxytocin, and I know oxytocin has already gottenas much hype as a hormone can get.
It even has its own cute nickname, the cuddle hormone, because it's releasedwhen you hug someone.
But this is a very small partof what oxytocin is involved in.
Oxytocin is a neuro-hormone.
It fine-tunesyour brain's social instincts.
It primes you to do things that strengthen close relationships.
Oxytocin makes you crave physical contactwith your friends and family.
It enhances your empathy.
It even makes you more willingto help and support the people you care about.
Some people have even suggestedwe should snort oxytocin.
to become more compassionate and caring.
But here's what most peopledon't understand about oxytocin.
It's a stress hormone.
Your pituitary gland pumps this stuff out as part of the stress response.
It's as much a partof your stress response as the adrenaline that makesyour heart pound.
And when oxytocin is releasedin the stress response, it is motivating you to seek support.
Your biological stress response is nudging you to tellsomeone how you feel, instead of bottling it up.
Your stress response wantsto make sure you notice when someone elsein your life is struggling so that you can support each other.
When life is difficult, your stress response wants youto be surrounded by people who care about you.
Okay, so how is knowing this sideof stress going to make you healthier? Well, oxytocin doesn't only acton your brain.
It also acts on your body, and one of its main roles in your body is to protect your cardiovascular systemfrom the effects of stress.
It's a natural anti-inflammatory.
It also helps your blood vesselsstay relaxed during stress.
But my favorite effect on the bodyis actually on the heart.
Your heart has receptors for this hormone, and oxytocin helps heart cells regenerate and heal from any stress-induced damage.
This stress hormonestrengthens your heart.
And the cool thingis that all of these physical benefits of oxytocin are enhancedby social contact and social support.
So when you reach outto others under stress, either to seek supportor to help someone else, you release more of this hormone, your stress response becomes healthier, and you actually recoverfaster from stress.
I find this amazing, that your stress responsehas a built-in mechanism for stress resilience, and that mechanism is human connection.
I want to finish by telling youabout one more study.
And listen up, because this studycould also save a life.
This study tracked about 1, 000 adultsin the United States, and they ranged in age from 34 to 93, and they started the study by asking, “How much stress have youexperienced in the last year?” They also asked, “How much time have you spenthelping out friends, neighbors, people in your community?” And then they used public recordsfor the next five years to find out who died.
Okay, so the bad news first: For every major stressful life experience, like financial difficultiesor family crisis, that increased the riskof dying by 30 percent.
But — and I hope youare expecting a “but” by now — but that wasn't true for everyone.
People who spent time caring for others showed absolutely no stress-relatedincrease in dying.
Caring created resilience.
And so we see once again that the harmful effectsof stress on your health are not inevitable.
How you think and how you act can transform your experience of stress.
When you choose to viewyour stress response as helpful, you create the biology of courage.
And when you choose to connectwith others under stress, you can create resilience.
Now I wouldn't necessarily askfor more stressful experiences in my life, but this science has given mea whole new appreciation for stress.
Stress gives us access to our hearts.
The compassionate heartthat finds joy and meaning in connecting with others, and yes, your pounding physical heart, working so hard to give youstrength and energy.
And when you choose to viewstress in this way, you're not just getting better at stress, you're actually makinga pretty profound statement.
You're saying that you can trust yourselfto handle life's challenges.
And you're rememberingthat you don't have to face them alone.
(Applause) Chris Anderson: This is kindof amazing, what you're telling us.
It seems amazing to methat a belief about stress can make so much differenceto someone's life expectancy.
How would that extend to advice, like, if someone is makinga lifestyle choice between, say, a stressful joband a non-stressful job, does it matter which way they go? It's equally wise to gofor the stressful job so long as you believethat you can handle it, in some sense? KM: Yeah, and one thingwe know for certain is that chasing meaningis better for your health than trying to avoid discomfort.
And so I would say that's reallythe best way to make decisions, is go after what it isthat creates meaning in your life and then trust yourself to handlethe stress that follows.
CA: Thank you so much, Kelly.
It's pretty cool.