“A wise man should consider that health is the greatest of human blessings and learn how by his own thought to derive benefit from his illnesses.”

—Hippocrates (Greek philosopher and physician, father of modern medicine)

It is now well known that stress can make you sick. At the same time, stress is a necessary part of life, unavoidable for us mere humans. So, the real question is not how to avoid stress, but how to live with it and stay healthy while coping with the stressors of life. In this chapter we discuss some of the research showing that hardiness, and the coping strategies that high-hardy people use in dealing with stress, is a big part of the answer.

In his fascinating book Why Zebras Don’t Get Ulcers, Robert Sapolsky outlines the many ways that stress can make us sick (Sapolsky, 2004). As we discussed in Chapter 8, the body’s stress response is healthy and adaptive when we are facing a true crisis or challenge. But it gets us into trouble when it’s not appropriate for the situation, when it goes on for too long, or when it’s triggered too often by events that don’t really call for a crisis response.

For example, if your blood pressure shoots up and you find yourself getting angry every time you’re in the slow checkout line at the grocery store, you’re probably having a stress response that is out of proportion to the situation. If this happens often enough, you’re probably putting yourself at risk for developing some stress-related health problem, which includes cardiovascular disease, high blood pressure, stroke, and diabetes. Stress, or how you handle stress, can also damage other parts of your body, such as the immune system, and increase your vulnerability to colds and flu as well as more serious diseases like arthritis and cancer.

Hardiness and Heart Disease

Heart disease and stroke are the number one causes of death around the world, killing around 18 million people a year. And stress is a major contributor (Castelli et al., 1986). One of the earliest studies looking at hardiness and heart disease was done by Howard and colleagues in 1986 (Howard, Cunningham, & Rechnitzer, 1986). They found that highly stressed managers who were low in hardiness developed high blood pressure and triglycerides over time, two markers for heart disease. But the managers who were high in hardiness did not develop these problems, despite their high stress levels. A similar study found that hardiness was a buffer against blood pressure rises in people exposed to a stressful laboratory task (Contrada, 1989).

Another study looked at adult students at the National Defense University in Washington, DC. These were mid-career professionals, both military and civilian, enrolled in a one-year intensive master’s degree program. All students received free health checks including cholesterol and blood glucose screenings. For this study, students also completed the Dispositional Resilience Scale, an earlier version of the Hardiness Resilience Gauge.

The study results showed that students who were high in hardiness had more of the good cholesterol (high density lipoprotein— HDL) and less of the bad (low density lipoprotein—LDL) in their bloodstreams (Bartone, Valdes, & Sandvik, 2016). Once again, this points to hardiness as a protective factor against heart disease and its precursors.

Another interesting study was done in Iran, comparing a group of coronary heart disease patients with a group of normal, healthy people (Hamid, 2007). Here, the healthy group showed significantly higher hardiness levels, and were also higher in social support, while also reporting lower levels of stress. So once again we see that hardiness appears as a protective factor, and that social support from family and friends can also act as a buffer against the ill effects of stress. This underscores an issue that we discussed more in Chapter 8, that people high in hardiness tend to appraise situations as less stressful to begin with, and so don’t experience the same kinds of stress reactions as low-hardy people do.

Stroke is also a serious consequence of heart disease. An interesting study on hardiness and stroke was done by Irene Hartigan for her doctoral dissertation research in Cork, Ireland. She studied 100 stroke survivors and wanted to see what factors distinguished those who adapted and were coping well after the stroke from those who were not. Hartigan measured hardiness with an earlier version of the Hardiness Resilience Gauge and also looked at physical functioning, living arrangements, and length of hospital stay as predictors.

What she found was that hardiness and physical functioning were the best predictors of positive adjustment in the post-stroke recovery period (Hartigan, 2015). So not only is hardiness a protective factor, but if you do end up with some kind of heart problem, being high in hardiness can help you recover and adjust better in the aftermath.

Hardiness and Diabetes

Diabetes is a serious illness that is on the rise, currently affecting over 135 million people worldwide, including many children (Moore, Zgibor, & Dasanayake, 2003). While many factors, including family background, can contribute to diabetes, stress is a major cause and can make diabetes worse for those who have it (Sapolsky, 2004). While there have not yet been studies of hardiness as a potential protective factor against diabetes, there are several studies on hardiness in diabetic patients.

It turns out that if you already have diabetes, and if your hardiness levels are high then you’re more likely to stick with the treatment regimen and manage the disease better over the long term (Ross, 1991). This means you can expect a better outcome. Along these same lines, insulin-dependent diabetes patients (also called type 1 diabetes) who are higher in hardiness show better physiological adaptation to the illness, better regulation of their blood sugar levels, and fewer eye and kidney problems (Pollack, 1989a).

Of course, it’s best not to get diabetes in the first place. Sticking to a healthy diet and exercising regularly can certainly help. But if you do end up with some form of diabetes, your hardiness mindset can help you deal with it in a more constructive and healthy way.

Hardiness and the Immune System

The immune system provides the body’s defenses against infection and disease. Ever since the 1960s, it’s been recognized that stress can damage the immune system and so increase our vulnerability to disease. Some of the earliest studies in this area found that when mice are stressed by exposing them to electric shock or loud noises, they are more susceptible to infection by viruses such as herpes simplex and poliomyelitis (Rasmussen, 1969).

Humans also show stress-related declines in immune system functioning. For example, studies have found that exposure to a variety of life stressors such as caring for the chronically ill or the death of a spouse is associated with impaired immune system responses (Kiecolt-Glaser & Glaser, 1991; Bartrop, Lazarus, Luckherst, & Kiloh, 1977). It’s even been shown that stress can increase your susceptibility to the common cold and flu (Cohen, Tyrell, & Smith, 1991).

Once again, not everyone reacts the same way to the stressors of life, and that’s true for the immune system too. It turns out that if you’re high in hardiness, your immune system seems to be not so bothered by stress. Researchers at the University of Texas-Austin were among the first to report on this, finding that blood samples from high-hardy individuals showed more robust immune responses when exposed to a variety of infectious agents (Dolbier et al., 2001).

A similar study drew blood samples from high-hardy and low-hardy students under examination stress and analyzed them for several markers of immune system functioning. Results showed that the high-hardy group had stronger and more balanced immune system responses (Ghafourian, Shiravi, Hamid, Hemmati, & Kooti, 2013). And a study in Norway found that navy cadets who were high in all three hardiness facets—challenge, control, and commitment—had healthier immune systems than those who were low in at least one of these elements (Sandvik et al., 2013).

So, what’s the bottom line? While there is more yet to learn about how hardiness may influence your immune system, the evidence to date points to a clear link between hardiness and better immune system functioning under stress. By cultivating a hardiness mindset of challenge, control, and commitment, you are likely keeping your immune system strong at the same time.

Hardiness and Cancer

As with heart disease and diabetes, stress is one of the factors that can increase your risk of getting some kind of cancer, although the evidence here is somewhat mixed. For example, a recent review of studies on stress and breast cancer found 26 studies that did identify a link. However, 18 studies in the review did not find any connection between stress and getting cancer (Chiriac, Baban, & Dumitrascu, 2018).

On the other hand, stress has definitely been found to be a factor in how fast cancer progresses. Multiple studies show that psychological stress contributes to cancer proliferation and tumor growth (Moreno-Smith, Lutgendorf, & Sood, 2010). And as with several other diseases, a major culprit seems to be an impaired immune system. For most people, the immune system just doesn’t work as well when they’re under a great deal of stress. When this happens, it’s easier for cancer to hide from the protective cells in your immune system, and then spread to other parts of your body (Calcagni & Elenkov, 2006).

Can hardiness play a role here? While there are not many studies bearing directly on this question, we know that hardiness contributes to a healthier immune system under stress. So, we can infer that hardiness may provide some protection against aspects of cancer that are stress related.

Other studies have been done that do show hardiness makes a positive difference for people who have been diagnosed with cancer, contributing to better adaptation, coping, and well-being (Seiler & Jenewein, 2019). For example, one study of Iranian women with breast cancer found that hardiness, as well as marital satisfaction, helped these women adjust positively to their condition, and even derive benefits from the experience (Aflakseir, Nowroozi, Mollazadeh, & Goodarzi, 2016).

Another study of breast cancer patients reported similar results, with women high in hardiness showing greater life satisfaction, despite the cancer (Taheri, Ahadi, Kashani, & Kermani, 2014). For Israeli survivors of malignant melanoma cancer, hardiness was positively related to well-being and level of functioning, and negatively related to distress (Hamama-Raz, 2012). Thus, the high-hardy survivors adjusted more positively to the cancer.

So, what does this mean for you? Hardiness is certainly no magic bullet. It won’t prevent you from getting cancer. However, if you should get cancer, being high in hardiness will help you to adjust and cope in a positive, healthy way.

Hardiness and Arthritis

Arthritis is a crippling disease that involves a breakdown of cartilage in the joints, leading to swelling, stiffness, and pain. Rheumatoid arthritis is a special type that is brought about by a disorder of the immune system. It’s known as an autoimmune disease, since the immune system is attacking its own bodily tissues. Of the various factors that can influence the severity and intensity of arthritis, psychological stress is a well recognized one (Walker, Littlejohn, McMurray, & Cutolo, 1999). Can hardiness provide any protection against this disease?

There are a few studies that have looked into this question. Researchers at the Arizona State University studied 33 women with rheumatoid arthritis, measuring hardiness and several indicators of health and immune system functioning (Okun, Zautra, & Robinson, 1988). They found that hardiness, and especially hardiness-control, was related to better perceived health and also a healthier immune system (circulating T cells). So, the women higher in hardiness control were adjusting better and maintaining better health than those low in hardiness control.

A similar study examined another, larger group of women (N = 122) with rheumatoid arthritis, looking at their hardiness, illness severity, and psychological well-being (Lambert, Lambert, Klipple, & Mewshaw, 1989). The results showed hardiness was a significant predictor of well-being in these patients, no matter the severity of the disease. So, in the case of rheumatoid arthritis, a hardiness mindset can not only help you cope with the disease, but appears to also influence how fast the disease progresses. This makes sense, since we know that hardiness is linked to a healthier immune system.

Health, Hardiness, and Social Support

In their study of arthritis patients, Vickie Lambert and her colleagues (1989) at Case Western Reserve University and Walter Reed Army Medical Center also found that social support was an important predictor of well-being for these patients. And patients who were high in hardiness were also high in social support. This suggests that arthritis patients high in hardiness may be better at developing and making use of support from friends and family in confronting stressful situations such as serious illness.

Of course, it’s also possible that social support, at least the right kinds of support, can help to increase your hardiness attitudes. When the social support you are getting encourages you to take steps to deal with problems, that is just the kind of coping that hardy people engage in. It’s known as “transformational coping” because it involves viewing the stressful situation as something you can manage by taking action and making use of the resources available (Kobasa & Puccetti, 1983). In so doing, you transform the event from a potentially damaging stressor into an opportunity to demonstrate and build up your capabilities.

Social support can also work in a negative way, if it encourages you to avoid dealing with your problems. For example, if you’re having a conflict with your boss at work, and your spouse offers sympathy while encouraging you to just not think about it and have another drink, that is avoidance coping. It’s not likely to solve anything, and the same problems will be there when you go to work the next day. It’s much better to think about ways to resolve the problem, perhaps by talking with your boss, or even changing jobs if necessary. This is the kind of active, problem-solving coping that people high in hardiness tend to use when dealing with stressful situations.

Hardiness and Sleep

Sleep is one of the most important things we can do to maintain our health, and one of the simplest. And most of us don’t get enough of it. According to the National Sleep Foundation, adults 26 to 64 years old need a minimum of seven hours of sleep a night in order to maintain good health (Hirshkowitz et al., 2015). And yet on average, over half of Americans (53%) report less sleep than that during the work week (National Sleep Foundation, 2013). Young people and teenagers need even more sleep, with a recommended 8–10 hours per night. However, most are getting only 7 to 7.5 hours on weeknights (Hansen, Janssen, Schiff, Zee, & Dubocovich, 2005). Lack of sleep can definitely make you sick, as well as degrade your well-being and performance.

For example, a study of high school students in Rhode Island found that those who were getting less sleep reported more illnesses including cold and flu, sore throat, muscle pain, fatigue, stomach problems, and (for women) menstrual pain (Orzech, Acebo, Seifer, Barker, & Carskadon, 2014). Many other studies have documented that poor quality sleep, or not enough sleep, increases your risk for a variety of illnesses including heart disease, obesity, and diabetes (Alvarez & Ayas, 2004). Sleep deprivation even makes you more vulnerable to the common cold (Cohen, Doyle, Alper, Janicki-Deverts, & Turner, 2009).

Can hardiness provide any protection against the ill effects of sleep loss? There is at least indirect evidence that it can, to some degree. We know from other studies that people high in hardiness tend to have stronger, more robust immune systems. Sleep deprivation disrupts the immune system, leaving us more susceptible to all the health problems mentioned above and more (Bryant, Trinder, & Curtis, 2004). So, to the extent hardiness contributes to a healthy, balanced immune system, the high-hardy person will be more tolerant of sleep loss.

There is some research support for this idea, and it comes from the world of shift workers. Shift workers, such as nurses, typically experience frequent sleep loss due to irregular hours and the disruption of their normal day/night circadian body clocks. You experience this yourself as jet lag whenever you have to travel across time zones. For example, in one study of shift work nurses in Norway, nurses who were high in hardiness showed greater tolerance and less fatigue, depression, and anxiety on the job than those low in hardiness (Natvik et al., 2011).

Similar findings come from another study of Norwegian nurses, this time looking at effects of shift work over a longer two-year period. Again, nurses high in hardiness showed less fatigue, anxiety, and depression over time. This study also looked at the three facets of hardiness and found that commitment and challenge had the strongest protective effects (Saksvik-Lehouillier, Bjorvatn, Magerøy, & Pallesen, 2016).

Are you a morning person or a night person? Some people are naturally more alert and active in the mornings. We call these early chronotypes, or larks. Others are more active later in the day and at night. These people are called late chronotypes, or owls. A growing body of research shows that compared to owls, larks are more resistant to the ill effects of shift work and sleep deprivation (Juda, Vetter, & Roenneberg, 2013; van de Ven et al., 2016).

A recent study looked at hardiness and chronotype in over 1,000 West Point military academy cadets. Life at West Point, which was discussed in Chapter 13, can be quite stressful for cadets, and sleep deprivation is common. In this study, cadets who were high in hardiness (especially control and commitment) tended to be larks, and they also performed better in their physical and military leadership programs (Kelly, Matthews, & Kelly, 2019). So, here is more evidence that being high in hardiness contributes to better sleep and provides some protection against the damaging effects of sleep deprivation.

Hardiness and Health Habits

One of the ways that hardiness can help to keep you healthy is by encouraging you to take up healthy practices, such as exercising, eating healthier foods, and even sleeping more. Being high in hardiness-commitment means in part being more plugged-in and engaged with the world around you. High hardy people are likely to be more aware of the value of exercise and other practices for maintaining their health. Being high in commitment also means you are more attuned to and interested in yourself, your own body and mind.

Being high in commitment means you are more aware of how different things in your environment, and your own choices and behaviors, can impact you. So, the person high in hardiness may choose to do things, like exercise, that help him or her stay healthy. And they may be more inclined to avoid the things, like smoking or eating high-sugar foods, that can make them sick. Likewise, being high in hardiness-control means you believe you can influence outcomes, so are more willing to make the choices and do the things that lead to good health, like exercising and not smoking.

An early study with Chicago executives found that both hardiness and exercise were valuable resources in buffering the ill effects of stress, as was social support from friends and family (Kobasa, Maddi, Puccetti, & Zola, 1985). In this study, hardiness and exercise were largely unrelated. This shows that you could be low in hardiness and still be a big exerciser or be high in hardiness and not much of an exerciser.

Still, there is plenty of evidence that hardiness is linked more directly to exercise and other healthy habits. For example, researchers at the University of Alabama tested out hardiness and a variety of health practices as possible buffers in the relation between stress and illness for undergraduates. In this study, health practices included exercise, diet, personal hygiene, and substance abuse (Wiebe & McCallum, 1986). The results showed that hardiness had a direct effect on health and also an indirect effect through health practices. In other words, students high in hardiness were engaging in more healthy practices (and fewer unhealthy ones), which in turn was leading them to better health outcomes (less illness). A more recent study in Japan looked at 468 college students and found that those who exercised regularly were also higher in hardiness (Monri, Tajima, & Matsueda, 2014). Interestingly, students who engaged in group exercise (as opposed to solo activities) were the highest of all in hardiness. This may relate to that aspect of commitment that involves engagement and interest in other people—the social world.

Other research shows that hardiness is related to healthy habits. For example, among adult patients suffering from a chronic illness, those who were high in hardiness were more involved with a variety of health promotion activities (Pollack, 1989b). Along the same lines, a study of older adults found that hardiness was linked with more exercise, healthy nutrition, relaxation practices, and general health promotion (Nicholas, 1993). Looked at another way, a study found that college students who were low in hardiness were more likely to engage in unhealthy habits, including smoking, doing drugs, poor diet, and lack of exercise (Nagy & Nix, 1989).

So, the evidence is pretty clear that if you’re high in hardiness, one of the ways you stay healthy under stress is by maintaining good health habits. Hardy people are more aware of how what they do can affect their health. And they are willing to make lifestyle choices that lead to better health. If you are high in hardiness, most likely you are paying attention to your diet, exercising, and looking for other ways to keep up your health.

Using the Three Cs of Hardiness to Stay Healthy

In this chapter we’ve covered some of the major health problems and areas where having a hardiness mindset can make a difference in keeping you healthy despite stressful life experiences. To be sure, many factors besides stress contribute to poor health or illness, including family history and exposure to infection and toxins in the environment. But being high in hardiness can help you deal with stress in ways that raise your resistance to illness and help you ward off many health problems. And if you should be unlucky enough to develop a major illness, a hardy outlook can help you adjust and cope more positively with the situation.

Sometimes, no matter what you do to stay healthy, illness knocks on your door. A few years ago, one of us (Paul) was diagnosed with late-stage throat cancer. Of course, this kind of news comes as a shock, and so I spent some time wondering if the doctors maybe had it wrong. But once I accepted the reality, I began to think about what I could do about it. My wife and I spent a lot of time researching different treatment options and went to several medical centers getting second and third opinions before settling on a treatment plan and hospital. As best we could, we took control of my medical care.

I also made choices throughout the treatment that I thought would lead to a better outcome. For example, the doctors recommended that I reduce my coffee intake, since caffeine can interfere with the effectiveness of treatment. Although I’d been a heavy coffee drinker for years, I quit drinking coffee completely at that point. I trusted the doctors’ advice and was fully committed to giving the treatment my best effort, regardless of the final result. Curiously enough, I came to see the cancer as an interesting challenge. It was certainly a new experience for me and provided an unusual and dramatic learning opportunity. Although like most of us I’d cared for family members with cancer, this was my first chance to experience it for myself on the patient side. It really gave me a new understanding and appreciation for what cancer patients go through. When you have cancer, no matter how good the treatment, you never know if you’ll live to tell the tale. It brings you face to face with your own death.

Sitting in the radiation oncology waiting room, or in the chemotherapy infusion center, I had a chance to observe and talk with other cancer patients, many of them worse off than I was. On an almost daily basis, I was amazed and humbled by the courage and dignity I saw in people of all ages who were struggling with some type of cancer. I also learned a lot about myself in going through it. While I wouldn’t wish it on anyone, I’m truly glad that I had this life experience.

So, what steps can you take to improve your odds of staying healthy? Your sense of hardiness-commitment involves an interest in yourself, as well as family, friends, and work. Use that commitment to yourself to examine your lifestyle and see if there are areas where you can shift your habits in a more healthy direction. This could involve exercise, diet, sleep, or something else. You’re worth it!

Your sense of hardiness-challenge also comes into play, reminding you that change is good, a chance to learn and get better. In this case, challenge yourself into some healthier habits. Maybe you need to exercise more or eat less or differently. Where can you make a change? Take the stairs instead of the elevator. Eat a more balanced diet. Have a salad now and then instead of that burger or pizza. Drink more water instead of sugary drinks. Go to bed earlier. You can try different things until you find the ones that fit in with your lifestyle and that you can keep up.

In making these changes, you’re also applying your sense of hardiness-control. You have the power to choose how you are going to live, how you spend your time, what you eat and drink. Control is never absolute, of course. We all have to accommodate to various demands and requirements of the society we live in. However, most of us have more control than we realize. Look around you and find something in your life that may be affecting your health in a bad way. Then think about what you can do to fix it!