The Role of Positive Psychology in Lifestyle Medicine

Abstract

Lifestyle medicine leverages six pillars—a predominantly plant-based diet, physical activity, sleep, avoiding risky substance, stress management, and social connection. Facilitating behavior change represents the crux of success with each of these pillars. Positive emotions and positive psychology constructs are shown to drive behavior change in the upward spiral theory of lifestyle change. Moreover, positive psychology interventions serve as additional, independent protective health factors. This paper offers a brief review of the empirical evidence for these roles of positive psychology and makes the case for explicitly adding positive psychology to the foundational lifestyle medicine pillars.

“Positive interventions can be relatively low-cost with significant potential benefits for health outcomes and lowering health care costs.”

Positive psychology constructs and approaches present powerful opportunities for lifestyle medicine practices to improve health outcomes. Outcomes can be improved through both enhancements in health behavior change approaches and direct effects on health which play a key role in the six pillars of lifestyle medicine—a predominantly plant-based diet, physical activity, sleep, avoiding risky substance, stress management, and social connection. This paper highlights results from meta-analyses of positive psychology interventions, as well as prospective studies linking these six pillars and positive psychology. When the latter are limited, we refer to cross-sectional studies and make a call for further research. We also provide brief practical tips for clinical implementation.

Health Behavior Change and Positive Psychology

The upward spiral theory of lifestyle change explains that positive affect can promote long-term achievement and maintenance of healthy behaviors by triggering nonconscious motivation for those behaviors. Individuals tend to make decisions to repeatedly engage in behaviors associated with positive emotions. Positive emotions also build additional social and other resources which reinforce the positive experience, further boosting motivation for behavior change. ¹

Health Outcomes and Positive Psychology

Health outcomes can be improved through the application of positive psychology in health care. Mediating mechanisms may include biological, behavioral, and psychosocial pathways. For example, empirical studies robustly show the link with cardiovascular disease (CVD), one of the most commonly treated conditions in lifestyle medicine practices. CVD may serve as a model for other conditions on how positive psychology constructs are linked with these diseases. One review of ten prospective studies with 136,265 participants found a 17% decrease in all-cause mortality and a 17% decrease in cardiovascular events for those with a higher purpose in life. ² Additional studies corroborated this significant association for CVD, ³ as well as for stroke. ⁴ Optimism is one specific construct shown to be prospectively associated with cardiovascular health. ⁵

The National Health and Nutrition Examination Survey I (6025 US men and women aged 25 to 74 years without CHD at baseline who were followed for a mean 15 years) reported that those with high baseline levels of emotional vitality had adjusted relative risk 19% lower for CHD than those with low emotional vitality. A dose-response relationship was demonstrated and remained significant after controlling for health behaviors and other potential confounders, including depressive symptoms. ⁶ More importantly for health care is that intentional positive psychology interventions demonstrate an impact on CVD. ⁷

Studies also indicate an impact of subjective well-being on health more broadly. After controlling for demographic and baseline health variables, subjective wellbeing, positive feelings, global life satisfaction and domain life satisfaction significantly predicted lowered risks of all-cause and natural-cause mortality in one general population study. Additionally, the first three significantly predicted lowered risk of unnatural-cause mortality. ⁸ Leading positive psychology researcher, Ed Diener, and colleagues reviewed seven types of evidence and concluded that high subjective well-being, such as life satisfaction, optimism, and positive emotions causes better health and longevity, controlling for health and socioeconomic status. ⁹

One meta-analysis that has particular relevance to medical community is a meta-analysis of 30 randomized, controlled trials of positive psychology interventions (PPIs) of 1864 adult participants with psychiatric (primarily depressive and anxiety disorders) or somatic disorders (primarily cancer, cardiac disease). The results showed a small, but significant effect of PPIs, including gratitude, kindness, and meaning-making interventions, on well-being and depression and a moderate effect on anxiety. The researchers concluded that PPIs are not just for patients with diseases that are primarily psychological in nature; they also can improve well-being for patients with somatic disorders. ¹⁰

Lastly, lifestyle medicine focuses on disease remission by addressing underlying inflammatory and pathologic processes caused by unhealthy lifestyle factors, including unhealthy eating and sedentary lifestyle. These detrimental inflammatory processes may be countered by positive psychology constructs independently of increasing healthy behaviors. For example, the experience of awe has been observed as a strong predictor of lower levels of proinflammatory cytokines, even when controlling for different personality and health variables. ¹¹

The Six Pillars of Lifestyle Medicine and Positive Psychology

The six pillars of lifestyle medicine have a reciprocal relationship with positive emotions. Positive psychology constructs can also be harnessed to address and coach for these healthy behaviors.

Healthy Eating

Eating healthy food, such as vegetables and fruits, is associated with positive affect and happiness.^12,13 At least 7-8 servings of fruit or vegetables per day are needed to see meaningful changes. ¹² Inversely, studies also reveal that feeling more positively can help individuals eat more healthfully.^14-18 One explanation is that positive emotions may increase the perceived importance of long-term goals such as health and also healthy eating can lead to more immediate feelings of wellbeing, reinforcing the desire to eat healthy foods.^12,19

Physical Activity

The empirical literature strongly supports the impact of physical activity on mood and mental health for both populations with and without mental illness. In fact, physical activity is as effective in treating depression as traditional treatments.^20-26 Physical activity increases positive moods; improvements in healthy adults can be seen with as little as 10 minutes of exercise. ²⁷ Both exercise and daily movement can contribute to mood improvement. ²⁸ As with healthy eating, physical activity has a reciprocal link with positive affect. ²⁹ Interventions that lead to positive emotions, especially those experienced during physical activity, and address factors that lead to negative affect, have the potential to effectively increase physical activity. ³⁰

Sleep

The average healthy adult requires between seven and seven and a half hours with a range of 7 to 9 hours to gain sleep’s physiologic and emotional benefits of sleep.^31,32

Sleep and emotions interact, as observed in empirical studies. Feelings of anxiety and sadness can interrupt sleep, and in turn, poor quality and inadequate sleep are associated with sadness, anger, and lower positive affect and psychological wellbeing.^33-36 Sleeping one and a half to two hours less than usual can lead to experiencing less positive affect. ³⁷ Inversely, both positive affect and eudaimonic well-being are shown to be associated with good sleep. ³⁴ However, empirical data is limited and more high-quality research is needed. ³⁸

Reducing Harm from and Avoiding Risky Substance Use

A healthy lifestyle includes avoidance of risky substance use to prevent and reverse physical and mental sequalae. Substance use, such as alcohol, has been linked with physical and mental health consequences. ³⁹ Lifestyle medicine practitioners can offer brief evidence-based interventions for risky substance use and mild to moderate substance use disorders, including motivational interviewing. Such interventions can leverage positive psychology. Having the capacity to envision a positive future with life purpose, pleasant experiences, and good relationships can support an individual in lowering substance use. Small steps of change may include reframing to see what is going well in one’s life and practicing gratitude. Leveraging character strengths has also been successfully implemented in managing substance use and in recovery for alcohol use, smoking and other addictions. ⁴⁰

Stress Management

Stress plays a role in unhealthy behaviors which underlie the conditions treated by lifestyle medicine. Positive psychology interventions have been shown to be effective in countering stress.^41,42 Savoring, planning positive activities, and pursuing meaningful goals are examples of positive psychology approaches that can help improve coping with life stressors, including major illnesses and caregiving. ⁴³ However, more research is needed to sort out which PPIs are effective in diverse populations and circumstances.

Social Connection

Social isolation has been associated with greater morbidity and mortality. ⁴⁴ Inversely, social connection is associated with improved health outcomes, including control of blood sugars, better cancer survival, decrease cardiovascular mortality, improved overall mental health and physical health, and greater happiness and longevity.^45,46 The Harvard Adult Development Study of more than eight decades of follow-up, after controlling for a wide range of cofounders, demonstrates that the single most important factor in health, wellbeing, happiness, and longevity is social connection. ⁴⁷ A key mechanism of action by which social connection promotes wellbeing is increases in vagal tone. Moreover, those with initially higher vagal tone levels increased their connectedness more rapidly than those with lower initial levels. These results suggest that social connection and well-being have a reciprocal relationship.^48,49 Weak social ties with acquaintances can also contribute to wellbeing. In one study, on the days students interacted with more classmates than usual, greater happiness and feelings of belonging were reported. ⁵⁰ High quality social connections can be developed through application of positive psychology-based activities, such as acts of kindness, shared laughter, expression of gratitude for the other, shared celebration of success, and more.^51-56

Conclusion

This brief review supports the significant role that positive psychology can play in lifestyle medicine.^57,58 Positive interventions can be relatively low-cost with significant potential benefits for health outcomes and lowering health care costs. To increase effective applications, more research is needed on the utilization of these positive psychology approaches in lifestyle medicine and traditional health care settings. For example, research is needed to identify which interventions are more beneficial for specific subpopulations.

While such studies are being conducted, lifestyle medicine practitioners can make simple and practical changes to harness lessons from the field of positive psychology. They can conduct brief assessments of positive emotions and life satisfaction, help patients notice and savor positive experiences during desired health behaviors, conduct health coaching that leverages positive future visioning and character strengths, inquire about patient interest in PPIs, and prescribe PPIs. Review of detailed clinical applications is beyond the scope of this paper and can be found in dedicated resources. ⁵⁹

Changes in clinical practice to harness positive psychology may help patients achieve positive health by promoting additional protective factors, as well as addressing traditional risk factors, to boost emotional, mental, and physical health outcomes and increase the capacity to fully thrive. In recognition of the important role that positive psychology can play in behavior change and health outcomes, lifestyle medicine leaders may consider including positive emotion-inducing activities to nudge behavior changes in all of the healthy lifestyle pillars and expanding the social connection pillar—or adding a new pillar—to emphasize positive psychology interventions as important elements of wellbeing.