If the self-care movement has taught us anything, it’s that happiness sells. That explains, at least in part, why meditation apps are becoming household names and self-care accounts are collecting millions of followers on Instagram. The allure of doing something—or, considering the man who swears by squeezing ice cubes, anything—to nurture happiness is too strong to pass up. But what does happiness actually deliver? The internet is home to enough articles, some peer-reviewed and others not quite, on links between happiness and mental health. And in some ways, it’s clear that being happy is generally good for the head. What’s less obvious, however, is the relationship between happiness and physical health. In study after study, researchers have found that happiness translates to big gains for patients’ overall well-being—but there’s no shortage of limitations. Here’s a glimpse of what the research says and what it means for physicians and patients alike. Does happiness really help health? The first thing to understand about happiness and health is that their relationship isn’t confined to any single area of the body or disease. In fact, the authors of a January 2019 literature review on this topic, published in the Annual Review of Psychology article, note that happiness, or positive affect, “is an essential component to our understanding of physical health.” The article goes on to examine measurements for health outcomes and their ties to happiness, along with 15 years’ worth of research into the biological, social, and behavioral components that could bridge positive affect and physical wellness. Mortality, particularly the length of life among healthy people, emerged as the most-studied outcome related to happiness, according to the review. Several analyses found that positive affect appeared most beneficial for older, healthy adults, but its effects were less apparent among middle-aged and young participants. People who experienced “high arousal” positive affect, meaning they were more excited and vigorous, appeared to swing the mortality studies in this direction, the authors noted. What about morbidity? The review authors found “impressive” diversity in associations among happiness and the onset of disease and incidence of injury, from cardiovascular disease and infection to physical decline. But the researchers argued that data sets on morbidity and positive affect were sometimes inconsistent, and some results couldn’t be replicated. That last point is the kicker: Time and again, meta-analyses and systematic reviews spotlight results suggesting that happiness is linked with mortality and morbidity in very real ways. But these same articles point out flaws, gaps, and inconsistencies in the body of research. “Happiness is generally associated with reduced mortality in prospective observational studies, albeit with several discrepant results,” writes the author of an April 2019 paper published in the Annual Review of Public Health. “Confounding and reverse causation are major concerns.” How does happiness boost health? Still, promising evidence exists. Here’s a look at some of the findings that researchers consider particularly worthy of hope. The authors of the aforementioned literature review point to cardiovascular outcomes as the most-examined area of happiness and health research. They cite large, well-controlled epidemiological studies of positive affect and heart disease, noting that some have found links between happiness and reduced stroke and lower hospital readmission rates after a cardiovascular event. (Still, the authors argue that certain studies use questionable assessment techniques, meaning we need more research.) Conversely, depression and distress have been linked to coronary heart disease, stroke, and type 2 diabetes, according to the Annual Review of Public Health article. What’s more, studies from across the globe have revealed associations among various kinds of mental well-being and lower incidence of coronary heart disease, the author wrote. Then there’s the study of 70,021 women, spanning 8 years, that found that people who were most optimistic saw a 38% reduction in heart disease mortality risk and a 39% drop in stroke mortality risk. Happiness and the fight against infectious diseases In fact, the authors of the aforementioned Annual Review of Psychology literature review argue that related studies centered on the cold and flu provide some of the best evidence in the space. In such experiments, in which participants were exposed to a respiratory virus, lower levels of positive affect prior to the exposure were tied with more signs of illness. “Furthermore, higher [positive affect] predicted resistance to both flu and cold, even after accounting for an array of related positive (optimism, extraversion, esteem, purpose), negative (NA), demographic, and health variables, replicating past similar work,” the authors wrote. Patients with HIV, meanwhile, saw slower disease progression and greater odds of suppressing viral load when they experienced positive feelings, according to the review. Compassionate love and other indicators of positive affect, such as meaning and altruism, were critical in this regard. But the review’s authors warned that these “promising” findings required some degree of skepticism. Research into disability and happiness appears encouraging, too. The author of the Annual Review of Public Health article pointed to a study that occurred over 8 years and found that people who reported higher levels of enjoyment of life benefited from a smaller number of impaired activities during daily life. Even the walking speed of participants who reported greater well-being decreased less, according to the review. In other studies, people with disabilities and a sense of purpose saw greater walking speeds and less intrusion into their daily activities. Can happiness aid clinical care? If these snapshots from the field are intriguing, so too is the chance that researchers might use insights into happiness and health to develop interventions. Don’t get too excited, though. Just as researchers are still working to understand the precise links between happiness and any number of health conditions, they have much to learn and do before interventions enter the clinic. Any intervention will likely need to be proven capable of fostering happiness for months, if not years, before it finds a place in medicine. Source