The Upside of Stress

contents

introduction

IF YOU HAD to sum up how you feel about stress, which statement would be more accurate?”

A) Stress is harmful and should be avoided, reduced, and managed.

B) Stress is helpful and should be accepted, utilized, and embraced.

Five years ago, I would have chosen A without a moment’s hesitation. I’m a health psychologist, and through all my training in psychology and medicine, I got one message loud and clear: Stress is toxic.

For years, as I taught classes and workshops, conducted research, and wrote articles and books, I took that message and ran with it. I told people that stress makes you sick; that it increases your risk of everything from the common cold to heart disease, depression, and addiction; and that it kills brain cells, damages your DNA, and makes you age faster. In media outlets ranging from the Washington Post to Martha Stewart Weddings, I gave the kind of stress-reduction advice you’ve probably heard a thousand times. Practice deep breathing, get more sleep, manage your time. And, of course, do whatever you can to reduce the stress in your life.

I turned stress into the enemy, and I wasn’t alone. I was just one of many psychologists, doctors, and scientists crusading against stress. Like them, I believed that it was a dangerous epidemic that had to be stopped.

But I’ve changed my mind about stress, and now I want to change yours.

Let me start by telling you about the shocking scientific finding that first made me rethink stress. In 1998, thirty thousand adults in the United States were asked how much stress they had experienced in the past year. They were also asked, Do you believe stress is harmful to your health?

Eight years later, the researchers scoured public records to find out who among the thirty thousand participants had died. Let me deliver the bad news first. High levels of stress increased the risk of dying by 43 percent. But—and this is what got my attention—that increased risk applied only to people who also believed that stress was harming their health. People who reported high levels of stress but who did not view their stress as harmful were not more likely to die. In fact, they had the lowest risk of death of anyone in the study, even lower than those who reported experiencing very little stress.

The researchers concluded that it wasn’t stress alone that was killing people. It was the combination of stress and the belief that stress is harmful. The researchers estimated that over the eight years they conducted their study, 182,000 Americans may have died prematurely because they believed that stress was harming their health.

That number stopped me in my tracks. We’re talking over twenty thousand deaths a year! According to statistics from the Centers for Disease Control and Prevention, that would make “believing stress is bad for you” the fifteenth-leading cause of death in the United States, killing more people than skin cancer, HIV/AIDS, and homicide.

As you can imagine, this finding unnerved me. Here I was, spending all this time and energy convincing people that stress was bad for their health. I had completely taken for granted that this message—and my work—was helping people. But what if it wasn’t? Even if the techniques I was teaching for stress reduction—such as physical exercise, meditation, and social connection—were truly helpful, was I undermining their benefit by delivering them alongside the message that stress is toxic? Was it possible that in the name of stress management, I had been doing more harm than good?

I admit, I was tempted to pretend that I never saw that study. After all, it was just one study—and a correlational study at that! The researchers had looked at a wide range of factors that might explain the finding, including gender, race, ethnicity, age, education, income, work status, marital status, smoking, physical activity, chronic health condition, and health insurance. None of these things explained why stress beliefs interacted with stress levels to predict mortality. However, the researchers hadn’t actually manipulated people’s beliefs about stress, so they couldn’t be sure that it was people’s beliefs that were killing them. Was it possible that people who believe that their stress is harmful have a different kind of stress in their lives—one that is, somehow, more toxic? Or perhaps they have personalities that make them particularly vulnerable to the harmful effects of stress.

And yet, I couldn’t get the study out of my head. In the midst of my self-doubt, I also sensed an opportunity. I’d always told my psychology students at Stanford University that the most exciting kind of scientific finding is one that challenges how you think about yourself and the world. But then I found the tables were turned. Was I ready to have my own beliefs challenged?

The finding I had stumbled across—that stress is harmful only when you believe it is—offered me an opportunity to rethink what I was teaching. Even more, it was an invitation to rethink my own relationship to stress. Would I seize it? Or would I file away the paper and continue to crusade against stress?

—

TWO THINGS in my training as a health psychologist made me open to the idea that how you think about stress matters—and to the possibility that telling people “Stress will kill you!” could have unintended consequences.

First, I was already aware that some beliefs can influence longevity. For example, people with a positive attitude about aging live longer than those who hold negative stereotypes about getting older. One classic study by researchers at Yale University followed middle-aged adults for twenty years. Those who had a positive view of aging in midlife lived an average of 7.6 years longer than those who had a negative view. To put that number in perspective, consider this: Many things we regard as obvious and important protective factors, such as exercising regularly, not smoking, and maintaining healthy blood pressure and cholesterol levels, have been shown, on average, to add less than four years to one’s life span.

Another example of a belief with long-reaching impact has to do with trust. Those who believe that most people can be trusted tend to live longer. In a fifteen-year study by Duke University researchers, 60 percent of adults over the age of fifty-five who viewed others as trustworthy were still alive at the end of the study. In contrast, 60 percent of those with a more cynical view on human nature had died.

Findings like these had already convinced me that when it comes to health and longevity, some beliefs matter. But what I didn’t know yet was whether how you think about stress was one of them.

The second thing that made me willing to admit I might be wrong about stress was what I know about the history of health promotion. If telling people that stress is killing them is a bad strategy for public health, it wouldn’t be the first time a popular health promotion strategy backfired. Some of the most commonly used strategies to encourage healthy behavior have been found to do exactly the opposite of what health professionals hope.

For example, when I speak with physicians, I sometimes ask them to predict the effects of showing smokers graphic warnings on cigarette packs. In general, they believe that the images will decrease smokers’ desire for a cigarette and motivate them to quit. But studies show that the warnings often have the reverse effect. The most threatening images (say, a lung cancer patient dying in a hospital bed) actually increase smokers’ positive attitudes toward smoking. The reason? The images trigger fear, and what better way to calm down than to smoke a cigarette? The doctors assumed that the fear would inspire behavior change, but instead it just motivates a desire to escape feeling bad.

Another strategy that consistently backfires is shaming people for their unhealthy behaviors. In one study at the University of California, Santa Barbara, overweight women read a New York Times article about how employers are beginning to discriminate against overweight workers. Afterward, instead of vowing to lose weight, the women ate twice as many calories of junk food as overweight women who had read an article on a different workplace issue.

Fear, stigma, self-criticism, shame—all of these are believed, by many health professionals, to be powerfully motivating messages that help people improve their well-being. And yet, when put to the scientific test, these messages push people toward the very behaviors the health professionals hope to change. Over the years, I’ve seen the same dynamic play out: Well-intentioned doctors and psychologists convey a message they think will help; instead, the recipients end up overwhelmed, depressed, and driven to self-destructive coping behaviors.

After I first discovered the study linking beliefs about stress to mortality, I started to pay more attention to how people reacted when I talked about the harmful effects of stress. I noticed that my message was met with the same kind of overwhelming feeling I would expect from medical warnings intended to frighten or shame. When I told exhausted undergraduate students about the negative consequences of stress right before final exam period, the students left the lecture hall more depressed. When I shared scary statistics about stress with caregivers, sometimes there were tears. No matter the audience, nobody ever came up afterward to say, “Thank you so much for telling me how toxic my stressful life is. I know I can get rid of the stress, but I’d just never thought to do it before!”

I realized that as much as I believed talking about stress was important, how I was doing it might not be helping. Everything I had been taught about stress management started from the assumption that stress is dangerous and that people needed to know this. Once they understood how bad stress was, they would reduce their stress, and this would make them healthier and happier. But now, I wasn’t so sure.

—

MY CURIOSITY about how your attitude toward stress influences its impact sent me on a search for more evidence. I wanted to know: Does how you think about stress really matter? And if believing that stress is bad is bad for you, what’s the alternative? Is there anything good about stress that’s worth embracing?

As I pored over scientific studies and surveys from the past three decades, I looked at the data with an open mind. I found evidence for some of the harmful effects we fear but also for benefits we rarely recognize. I investigated the history of stress, learning more about how psychology and medicine became convinced that it is toxic. I also talked to scientists who are part of a new generation of stress researchers, whose work is redefining our understanding of stress by illuminating its upside. What I learned from these studies, surveys, and conversations truly changed the way I think about stress. The latest science reveals that stress can make you smarter, stronger, and more successful. It helps you learn and grow. It can even inspire courage and compassion.

The new science also shows that changing your mind about stress can make you healthier and happier. How you think about stress affects everything from your cardiovascular health to your ability to find meaning in life. The best way to manage stress isn’t to reduce or avoid it, but rather to rethink and even embrace it.

So, my goal as a health psychologist has changed. I no longer want to help you get rid of your stress—I want to make you better at stress. That is the promise of the new science of stress, and the purpose of this book.

About This Book

This book is based on a course I teach through Stanford Continuing Studies called the New Science of Stress. The course, which enrolls people of all ages and from all walks of life, is designed to transform the way we think about and live with stress.

It’s helpful to know a little about the science behind embracing stress for two reasons. First, it’s fascinating. When the subject is human nature, every study is an opportunity to better understand yourself and those you care about. Second, the science of stress has some real surprises. Certain ideas about stress—including the central premise of this book: that stress can be good for you—are hard to swallow. Without evidence, it would be easy to dismiss them. Seeing the science behind these ideas can help you consider them and how they might apply to your own experiences.

The advice in this book isn’t based on one shocking study—even though that’s what inspired me to rethink stress. The strategies you’ll learn are based on hundreds of studies and the insights of dozens of scientists I’ve spoken with. Skipping the science and getting straight to the advice doesn’t work. Knowing what’s behind every strategy helps them stick. So this book includes a crash course in the new science of stress and what psychologists call mindsets. You’ll be introduced to rising-star researchers and some of their most intriguing studies—all in a way that I hope any reader can enjoy. If you have a bigger appetite for scientific details and want even more information, the notes at the end of this book will let you dig deeper.

But most important, this is a practical guide to getting better at living with stress. Embracing stress can make you feel more empowered in the face of challenges. It can enable you to better use the energy of stress without burning out. It can help you turn stressful experiences into a source of social connection rather than isolation. And finally, it can lead you to new ways of finding meaning in suffering.

Throughout this book, you’ll find two types of practical exercises to try:

The Rethink Stress exercises in Part 1 are designed to shift your way of thinking about stress. You can use them as writing prompts or as any other forms of self-reflection that work for you. You might think about the topic while you’re on the treadmill at the gym or riding the bus to work. You can make it a private reflection or use it to start a conversation. Talk about it with your spouse over dinner or bring it up at your parents’ group at church. Write a Facebook post about it and ask your friends for their thoughts. Along with helping you think differently about stress in general, these exercises also encourage you to reflect on the role that stress plays in your life, including in relation to your most important goals and values.

The Transform Stress exercises in Part 2 include on-the-spot strategies to use in moments of stress, as well as self-reflections that will help you cope with specific challenges in your life. They will help you tap into your reserves of energy, strength, and hope when you’re feeling anxious, frustrated, angry, or overwhelmed. Transform Stress exercises rely on what I call “mindset resets”—shifts in how you think about the stress you are experiencing in the moment. These mindset resets can alter your physical stress response, change your attitude, and motivate action. In other words, they transform the effect that stress is having on you in the very moment you are feeling stressed. These exercises are based on scientific studies, and I encourage you to treat them like experiments yourself. Try them out and see what works for you.

All the exercises in this book have been shaped by the feedback of my students and by my experiences sharing these ideas with communities around the world, including with educators, medical professionals, executives, professional coaches, family therapists, and parents. I’ve included the practices that people tell me have been personally and professionally meaningful, leading to change in their own lives and in the communities they work with.

Together, these exercises will help you change your relationship with stress. It might feel weird to think about having a relationship with stress, especially if you’re used to thinking of stress as something that happens to you. But you do have a relationship with stress. You might feel victimized by stress—helpless against it or held hostage by it. Or maybe yours is a love-hate relationship—relying on stress to reach your goals but worried about its long-term consequences. Perhaps you feel like you are in a constant struggle with stress, trying to reduce, avoid, or manage it without ever being able to control it. Or maybe you feel like the stressful experiences in your past have too much sway over your present self. You might view stress as your enemy, an unwanted guest, or a partner you aren’t quite sure you can trust. Whatever your current relationship with stress, how you think about it and how you respond to it both play an important role in how it affects you. By rethinking and even embracing stress, you can change its effect on everything from your physical health and emotional well-being to your satisfaction at work and hopefulness about the future.

Throughout the book, we’ll also consider how the science of stress and mindsets can help you support the people, communities, and organizations you care about. How can we nurture resilience in our loved ones? What would it look like for a workplace culture to embrace stress? How do people build support networks to deal with trauma or loss? I’ll introduce you to some of my favorite programs that are using this science to create communities that are able to transform suffering into growth, meaning, and connection. These programs can serve as models and inspiration, demonstrating what it looks like to translate science into service, and abstract ideas into actions with impact.

Will This Book Help Me with My Stress?

So far, I’ve avoided defining stress—in part because the word has become a catchall term for anything we don’t want to experience and everything that’s wrong with the world. People use the word stress to describe both a traffic delay and a death in the family. We say we’re stressed when we feel anxious, busy, frustrated, threatened, or under pressure. On any given day, you might find yourself getting stressed out by email, politics, the news, the weather, or your growing to-do list. And the biggest source of stress in your life right now could be work, parenting, dealing with a health crisis, getting out of debt, or going through a divorce. Sometimes we use the word stress to describe what’s going on inside us—our thoughts, emotions, and physical responses—and sometimes we use it describe the problems we face. Stress is commonly used to describe trivial irritations, but it’s just as likely to be shorthand for more serious psychological challenges such as depression and anxiety. There is no single definition of stress that can encompass all these things, and yet we use that word to refer to all of them.

The fact that we use the word stress to describe so much of life is both a blessing and a curse. The downside is that it can make talking about the science of stress tricky. Even scientists—who usually nail down their definitions—use stress to describe a mind-boggling array of experiences and outcomes. One study might define it as feeling overwhelmed by caregiving demands, while another looks at it in terms of workplace burnout. One study uses stress to describe daily hassles, while another uses it to talk about the long-term effects of trauma. Worse yet, when this science gets communicated in the media, the headlines often use the familiar word stress but fail to provide details about what a study actually measured, leaving you to guess at whether the findings apply to your own life.

At the same time, there is a benefit to the catchall nature of the word. Because we use stress to describe so many aspects of life, how you think about it has a profound effect on how you experience life. Changing your thoughts about stress can have a similarly profound effect, transforming both everyday aggravations and how you relate to the biggest life challenges. So, rather than try to offer a narrow and manageable definition of stress, I’m willing to keep the meaning broad. Yes, it would be easier to say, “This book is about thriving under pressure at work” or “This book will help you manage the physical symptoms of anxiety.” But the transformative power of choosing to see the upside of stress comes from its ability to change how you think about, and relate to, so many different aspects of life.

So as we begin this journey together, I offer this conception of stress: Stress is what arises when something you care about is at stake. This definition is big enough to hold both the frustration over traffic and the grief over a loss. It includes your thoughts, emotions, and physical reactions when you’re feeling stressed, as well as how you choose to cope with situations you’d describe as stressful. This definition also highlights an important truth about stress: Stress and meaning are inextricably linked. You don’t stress out about things you don’t care about, and you can’t create a meaningful life without experiencing some stress.

My goal, in writing this book, is to provide science, stories, and strategies that address the full range of what we mean by stress, even knowing that not every example will resonate with you, and that it is impossible to address every aspect of human experience that gets labeled as “stressful.” We’ll look at academic stress, work stress, family stress, health stress, financial stress, and social stress, as well as the challenges of dealing with anxiety, depression, loss, and trauma—things that might be best described as suffering, but that come up whenever I invite people to think about the stress in their own lives. I’ve also included the voices of my students to tell you how they have applied the ideas in this book. I’ve changed the names and some identifying details of those who wished to stay anonymous. But know that these are real stories from real people who hope that by sharing their experiences, they will help you have a different experience of stress. You’ll also feel their presence throughout the book in the questions and concerns I try to address. I am grateful to them for helping me learn more about what it means to embrace stress in circumstances far different from my own.

I trust you to pay the most attention to the science and stories that fit your life right now. The same applies to the exercises and strategies in the book. Just as no scientific study applies to all forms of stress, no one strategy for dealing with stress applies to every situation. A strategy that allows you to overcome public-speaking anxiety or better handle family conflict may not be the one that best helps you deal with financial problems or manage grief. I encourage you to choose the methods that seem best suited to your own challenges.

Whenever I talk about the upside of stress, someone always asks, “But what about the really bad stress? Does what you’re saying still apply?” It’s easy for people to see how embracing the small stress—some pressure at work, a little nervousness about a major event—could help. But what about the big stuff? Does the concept of embracing stress apply to trauma, loss, health problems, and chronic stress?

I can’t guarantee that every idea in this book is going to help with every form of stress or suffering. However, I no longer worry that the benefits of embracing stress apply only to the small stuff. To my surprise, embracing stress has helped me the most in the most difficult situations—dealing with the death of a loved one, coping with chronic pain, and even overcoming a paralyzing fear of flying. That’s also what I’ve heard from my students. The stories they share at the end of the course usually aren’t about getting better at juggling deadlines or dealing with an irritating neighbor. They are about coming to terms with the loss of a spouse. Facing a lifelong struggle with anxiety. Making peace with a past that includes childhood abuse. Losing a job. Getting through cancer treatment.

Why would seeing the good in stress help in these circumstances? I believe it is because embracing stress changes how you think about yourself and what you can handle. It is not a purely intellectual exercise. Focusing on the upside of stress transforms how you experience it physically and emotionally. It changes how you cope with the challenges in your life. I wrote this book with that specific purpose in mind: to help you discover your own strength, courage, and compassion. Seeing the upside of stress is not about deciding whether stress is either all good or all bad. It’s about how choosing to see the good in stress can help you meet the challenges in your life.

PART 1

STRESS

CHAPTER 1

I STOOD IN THE Behavioral Research Lab at Columbia University holding my right arm out at shoulder height. Psychologist Alia Crum was trying to push it down. We struggled for a few seconds. Despite being quite petite, she was surprisingly strong. (I later learned that Crum had actually played Division I ice hockey in college and is currently an internationally ranked Ironman triathlete.)

My arm gave out.

“Now, instead of resisting me, I want you to imagine that you are reaching your arm toward someone or something you care about,” Crum said. She asked me to imagine that when she pushed on my arm, I could channel her energy into what I was reaching toward. The exercise was inspired by her father, who is a sensei in aikido, a martial art based on the principle of transforming harmful energy. I visualized what Crum had instructed, and we tried again. This time, I was much stronger, and she wasn’t able to push my arm down. The more she pushed, the stronger I felt.

“Were you really trying as hard this time?” I asked.

Crum beamed. She had just demonstrated the single idea that motivates all her research: How you think about something can transform its effect on you.

I was meeting Crum in her basement lab at the Columbia Business School to talk about her research on stress. For a young scientist, Crum has an unusual track record of high-profile findings. Her work gets attention because it shows that our physical reality is more subjective than we believe. By changing how people think about an experience, she can change what’s happening in their bodies. Her findings are so surprising that they make a lot of people scratch their heads and say, “Huh? Is that even possible?”

This reaction—Is that even possible?—is a familiar one to researchers who study mindsets. Mindsets are beliefs that shape your reality, including objective physical reactions (like the strength of my arm as Crum pushed on it), and even long-term health, happiness, and success. More important, the new field of mindset science shows that a single brief intervention, designed to change how you think about something, can improve your health, happiness, and success, even years into the future. The field is full of remarkable findings that will make you think twice about your own beliefs. From placebos to self-fulfilling prophecies, perception matters. After this crash course in the science of mindsets, you’ll understand why your beliefs about stress matter—and how you can start to change your own mind about stress.

The Effect You Expect Is the Effect You Get

“Thinking Away the Pounds” and “Believe Yourself Healthy” were just two of the headlines that heralded the publication of one of Alia Crum’s earliest studies. Crum had recruited housekeepers at seven hotels across the United States for a study of how beliefs affect health and weight. Housekeeping is strenuous work, burning over 300 calories an hour. As exercise, that puts it on par with weight lifting, water aerobics, and walking at 3.5 miles per hour. In comparison, office work—such as sitting in meetings or working on a computer—burns roughly 100 calories an hour. And yet, two-thirds of the housekeepers Crum recruited believed they weren’t exercising regularly. One-third said they got no exercise at all. Their bodies reflected this perception. The average housekeeper’s blood pressure, waist-to-hip ratio, and body weight were exactly what you’d expect to find if she were truly sedentary.

Crum designed a poster that described how housekeeping qualified as exercise. Lifting mattresses to make beds, picking towels off the floor, pushing heavily loaded carts, and vacuuming—these all require strength and stamina. The poster even included the calories burned while doing each activity (for example, a 140-pound woman would burn 60 calories cleaning bathrooms for fifteen minutes). At four of the seven hotels, Crum communicated this information to the housekeepers in a fifteen-minute presentation. She also hung copies of the poster, in both English and Spanish, on the bulletin boards in the housekeepers’ lounges. Crum told them that they were clearly meeting or exceeding the surgeon general’s recommendations for physical exercise and should expect to see the health benefits of being active. The housekeepers at the other three hotels were a control group. They received information about how important physical exercise is for health, but they were not told that their work qualified as exercise.

Four weeks later, Crum checked in with the housekeepers. Those who had been informed that their work was exercise had lost weight and body fat. Their blood pressure was lower. They even liked their jobs more. They had not made any changes in their behavior outside work. The only thing that had changed was their perception of themselves as exercisers. In contrast, housekeepers in the control group showed none of these improvements.

So, does this mean that if you tell yourself that watching television burns calories, you can lose weight? Sorry, no. What Crum told the housekeepers was true. The women really were exercising. Yet when she met them, they didn’t see their work that way. Instead, they were more likely to view housekeeping as hard on their bodies.

Crum’s provocative hypothesis is that when two outcomes are possible—in this case, the health benefits of exercise or the strain of physical labor—a person’s expectations influence which outcome is more likely. She concluded that the housekeepers’ perception of their work as healthy exercise transformed its effects on their bodies. In other words, the effect you expect is the effect you get.

Crum’s next headline-making study pushed this idea further. The “Shake Tasting Study” invited hungry participants to come to the laboratory at eight in the morning after an overnight fast. On their first visit, participants were given a milkshake labeled “Indulgence: Decadence You Deserve,” with a nutritional label showing 620 calories and 30 grams of fat. On their second visit, one week later, they drank a milkshake labeled “Sensi-Shake: Guilt-Free Satisfaction,” with 140 calories and zero grams of fat.

As the participants drank the milkshakes, they were hooked up to an intravenous catheter that drew blood samples. Crum was measuring changes in blood levels of ghrelin, also known as the hunger hormone. When blood levels of ghrelin go down, you feel full; when blood levels go up, you start looking for a snack. When you eat something high in calories or fat, ghrelin levels drop dramatically. Less-filling foods have less impact.

One would expect a decadent milkshake and a healthful one to have a very different effect on ghrelin levels—and they did. Drinking the Sensi-Shake led to a small decline in ghrelin, while consuming the Indulgence shake produced a much bigger drop.

But here’s the thing: The milkshake labels were a sham. Both times, participants had been given the same 380-calorie milkshake. There should have been no difference in how the participants’ digestive tracts responded. And yet, when they believed that the shake was an indulgent treat, their ghrelin levels dropped three times as much as when they thought it was a diet drink. Once again, the effect people expected—fullness—was the outcome they got. Crum’s study showed that expectations could alter something as concrete as how much of a hormone the cells of your gastrointestinal tract secrete.

In both the housekeeping and the milkshake studies, when people’s perceptions changed, their bodies’ responses changed. And in each study, one particular belief seemed to enhance the body’s most adaptive response: Viewing physical labor as exercise helped the body experience the benefits of being active. Viewing a milkshake as a high-calorie indulgence helped the body produce signals of fullness.

As interesting as weight loss and hunger hormones were, Crum was curious what other outcomes might be influenced by how we view things. Is there a perception that shapes our health in even bigger ways? She began to wonder about stress. She knew that most people view stress as harmful, even though it can also be beneficial. That’s two possible effects. Could the effect that stress has on your well-being be determined, in part, by which effect you expect? And if Crum could change how a person thought about stress, would that change the way the person’s body responded?

—

THAT QUESTION is why I found myself in Alia Crum’s laboratory on a sunny morning in April. After I took the stairs down to the windowless basement and exchanged some pleasant introductions with the lab team, one of Crum’s graduate students strapped me into what an outside observer might suspect was torture equipment. Two bands of metallic tape were wrapped tightly around my rib cage, and two around my neck. The bands were attached to an impedance cardiography machine that measured the activity of my heart. One blood pressure cuff squeezed my left bicep, while another gripped the index finger of my left hand. Electrodes on my inner elbow, fingertips, and leg measured blood flow and sweating. A thermometer attached to my right pinkie finger kept track of my body temperature. Then a lab assistant asked me to drool into a tiny test tube so that my saliva could be analyzed for stress hormones.

I was here to experience for myself what participants in Crum’s most recent study had gone through. The goal of the study was to manipulate participants’ views of stress and then watch how their bodies responded to a stressful situation.

The stress I was about to face was a mock job interview. To help me get better at interviewing, the mock interviewers would give me feedback as we went along. But this wasn’t ordinary role-play. To make it extra stressful, the interviewers were trained to give me (and every other participant) negative feedback no matter what I said or did. My eye contact was poor. I picked a bad example. I uttered too many “uhs” and “ums.” My posture suggested that I lacked confidence. They asked tough questions, like “Do you think gender inequality at the workplace is still a problem?” No matter what I or any participant said, the evaluators criticized the answers. Even though I knew that the whole thing was a carefully scripted experiment designed to throw me off balance, it was still stressful.

Before the mock job interview, every study participant was randomly assigned to view one of two videos about stress. The three-minute video I got opened with the message, “Most people think that stress is negative . . . but actually research shows that stress is enhancing.” The video went on to describe how stress can improve performance, enhance well-being, and help you grow. The other video, which half the participants in the study watched, started with the ominous announcement, “Most people know that stress is negative . . . but research shows that stress is even more debilitating than you expect.” The video went on to describe how stress can harm your health, happiness, and performance at work.

Both videos cited real research, so in this sense they were both true. But each video was designed to activate a specific perception of stress—one that Crum hoped would influence how participants’ bodies responded to the stress that followed.

I went through this mock experiment months after Crum had finished conducting the study. That meant that as soon as I finished the job interview and the electrodes came off, I got to hear the preliminary results. One finding blew me away.

The saliva I had drooled into the test tube provided a sample of two stress hormones: cortisol and dehydroepiandrosterone (DHEA). These hormones are both released by your adrenal glands during times of stress, but they serve different roles. Cortisol helps turn sugar and fat into energy and improves the ability of your body and brain to use that energy. Cortisol also suppresses some biological functions that are less important during stress, such as digestion, reproduction, and growth. DHEA, on the other hand, is a neurosteroid, which is exactly what it sounds like: a hormone that helps your brain grow. In the same way that testosterone helps your body grow stronger from physical exercise, DHEA helps your brain grow stronger from stressful experiences. It also counters some of the effects of cortisol. For example, DHEA speeds up wound repair and enhances immune function.

You need both of these hormones, and neither is a “good” nor “bad” stress hormone. However, the ratio of these two hormones can influence the long-term consequences of stress, especially when that stress is chronic. Higher levels of cortisol can be associated with worse outcomes, such as impaired immune function and depression. In contrast, higher levels of DHEA have been linked to a reduced risk of anxiety, depression, heart disease, neurodegeneration, and other diseases we typically think of as stress-related.

The ratio of DHEA to cortisol is called the growth index of a stress response. A higher growth index—meaning more DHEA—helps people thrive under stress. It predicts academic persistence and resilience in college students, as well as higher GPAs. During military survival training, a higher growth index is associated with greater focus, less dissociation, and superior problem-solving skills, as well as fewer post-traumatic stress symptoms afterward. The growth index even predicts resilience in extreme circumstances, such as recovering from child abuse.

Crum wanted to see if changing people’s perceptions of stress could modify this measure of resilience. Could a three-minute video about stress alter this key ratio of stress hormones?

The answer, amazingly, is yes.

The videos had no effect on cortisol levels. Everyone’s cortisol went up during the mock interview, as expected. However, participants who had watched the stress-is-enhancing video before the interview released more DHEA and had a higher growth index than participants who had watched the stress-is-debilitating video. Viewing stress as enhancing made it so—not in some subjective, self-reported way, but in the ratio of stress hormones produced by the participants’ adrenal glands. Viewing stress as helpful created a different biological reality.

From Placebo to Mindset

One way to think about Crum’s stress study is that it demonstrated a placebo effect. The positive stress video changed participants’ expectations of how stress would affect them and, like a sugar pill, produced the expected response.

The placebo effect is a powerful phenomenon, but it’s also a manipulation. Someone is telling you how to think about something. Often, they are giving you something you don’t have any preconceived notions about. They hand you a pill and say, “This will help,” so you believe them. But when it comes to stress, everyone already has a point of view. Every time you experience stress, your beliefs about it come to mind. Think about how many moments of your day you would describe as stressful. How often do you say, “This is so stressful” or “I’m so stressed”? In each of these moments, how you think about stress can alter your biochemistry and, ultimately, how you respond to whatever has triggered the stress.

A belief with this kind of power goes beyond a placebo effect. This is a mindset effect. Unlike a placebo, which tends to have a short-lived impact on a highly specific outcome, the consequences of a mindset snowball over time, increasing in influence and long-term impact.

As we’ve seen, a mindset is a belief that biases how you think, feel, and act. It’s like a filter that you see everything through. Not every belief can become a mindset. Some beliefs simply aren’t that important. You might believe that chocolate is better than vanilla, that it’s rude to ask somebody’s age, and that the world is round, not flat. Those beliefs, no matter how strongly you hold them, have relatively little consequence for how you think about your life.

The beliefs that become mindsets transcend preferences, learned facts, or intellectual opinions. They are core beliefs that reflect your philosophy of life. A mindset is usually based on a theory about how the world works. For example, that the world is getting less safe, that money will make you happy, that everything happens for a reason, or that people cannot change. All of these beliefs have the potential to shape how you interpret experiences and make decisions. When a mindset gets activated—by a memory, a situation you find yourself in, or a remark someone makes—it sets off a cascade of thoughts, emotions, and goals that shape how you respond to life. This, in turn, can influence long-term outcomes, including health, happiness, and even longevity.

Take, for example, how you think about growing older. As I mentioned before, having a positive view of aging adds an average of almost eight years to one’s life. It predicts other important health outcomes, too. For example, the Baltimore Longitudinal Study of Aging, which tracked adults ages eighteen to forty-nine for an impressive thirty-eight years, found that those with the most positive views of aging had an 80 percent lower risk of heart attack. Beliefs about aging also influence recovery from major illnesses and accidents. In one study, adults who associated growing older with positive stereotypes such as “wise” and “capable” recovered from a heart attack more quickly than those who endorsed negative stereotypes such as “useless” and “stuck in their ways.” In another study, a positive view of aging predicted faster and more complete physical recovery from a debilitating illness or accident. Importantly, both studies measured recovery in objective outcomes, such as walking speed, balance, and ability to perform daily activities. (By the way, if these findings make you want to adopt a more positive view of aging, consider this: Studies consistently show that people get happier as they get older, even though younger adults find this difficult to believe.)

How exactly does a belief about aging—sometimes measured decades earlier—affect heart attack rates, disability, and the risk of dying? The studies all controlled for important factors such as initial health status, depression, and socioeconomic status, so these do not explain the effects.

Instead, one likely answer is health behaviors. People with a negative view of aging are more likely to view poor health as inevitable. Because they feel less capable of maintaining or improving their health as they age, they invest less time and energy in their future well-being. In contrast, people with a positive attitude toward growing older engage in more health-promoting behaviors, like exercising regularly and following their doctor’s advice. Changing a person’s mind about aging can even promote healthy behaviors. For example, an intervention designed to increase positive views of aging also increased participants’ physical activity. When you have a positive view of growing older, you’re more apt to do things that will benefit your future self.

Beliefs about aging have an especially big impact on behaviors following a major health challenge. Researchers at the German Centre of Gerontology in Berlin followed older adults over time to examine the impact of a serious illness or accident, such as a broken hip, lung disease, or cancer. Those with a positive view of aging responded to the crisis by increasing their commitment to their health. They were more proactive and dedicated to their recovery. In contrast, older adults who had a more negative view of aging were less likely to take actions to improve their health. These choices, in turn, influenced recovery. Participants with a more positive view of aging ended up reporting greater life satisfaction, as well as better physical health and physical function, after their illness or accident.

How you think about aging can even influence your will to live as you grow older. People who hold negative views of aging when they are middle-aged report less of a will to live later in life. As older adults, they are more likely to view their lives as empty, hopeless, or worthless. In one study, Yale psychologists tested the effects of beliefs about aging on the will to live by subliminally priming older adults with either negative or positive stereotypes about aging. The researchers then asked the older adults to make hypothetical medical decisions. Older adults who had been primed with positive stereotypes were more likely to agree to a life-prolonging intervention for a potentially fatal illness. In contrast, those exposed to negative stereotypes were more likely to reject treatment.

Findings like this suggest that how you think about aging affects health and longevity not through some mystical power of positive thinking but by influencing your goals and choices. This is a perfect example of a mindset effect. It is more powerful than a placebo effect because it doesn’t just alter your present experience but also influences your future.

It turns out that how you think about stress is also one of those core beliefs that can affect your health, happiness, and success. As we’ll see, your stress mindset shapes everything from the emotions you feel during a stressful situation to the way you cope with stressful events. That, in turn, can determine whether you thrive under stress or end up burned out and depressed. The good news is, even if you are firmly convinced that stress is harmful, you can still cultivate a mindset that helps you thrive.

What Is Your Stress Mindset?