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Adolescents with high positive affect may have improved physical and mental health as adults, according to a study published April 2 in the open-access journal PLOS Medicine by Eric Kim and Renae Wilkinson from Harvard University, US, and colleagues.
Positive affect is the experience of pleasurable emotions, such as happiness, joy, excitement, and calm. Research on adults has shown that positive affect is associated with healthier behaviors and decreased risk of chronic diseases, but data are limited in adolescents. Given that adolescence is a critical time for establishing healthy mindsets and behaviors, it represents a key period for interventions aimed at setting people on a healthier life course.
In this study, researchers used data from a prospective, representative sample of approximately 10,000 U.S. adolescents in grades 7-12 (aged about 15-18) in the mid-1990s who were followed into adulthood. Participants reported on aspects of their background, health, and well-being at several time points throughout the study.
The researchers grouped participants based on how much their positive affect increased over one year during adolescence. They then assessed whether adolescents with a higher increase in positive affect had healthier outcomes as adults based on 41 outcomes related to physical health, healthy behavior, mental and psychological well-being, and prosocial behavior.
The results show that adolescents with higher increases in positive affect scored higher on several outcomes within each of these categories, even after controlling for demographic and other variables that may bias the results. One of the biggest effects was seen in mental health, where positive affect was associated with a lower likelihood of ADD/ADHD, anxiety, depression, and stress.
The study suggests that interventions designed to improve positive affect may have enduring impacts into adulthood, though the researchers note the limitations in using self-reported data and the possibility of additional confounding factors that they didn’t consider.
The authors add, “Several prominent organizations like the OECD, WHO, and UN are advocating for nations to integrate well-being indicators alongside economic indicators when sculpting policies. Emerging evidence from randomized controlled trials aimed at individuals, and case studies of successful policies aimed at entire populations, suggest positive affect can be enhanced. Our findings suggest that targeting positive affect during adolescence, a critical developmental phase for acquiring health assets and establishing healthy mindsets, is a promising point of intervention that might enhance the trajectory of health/well-being in adulthood.”