While enduring hunger pangs and engaging in grueling exercise regimens have their adherents among those seeking a longer life span, a study described in an article published online this week in the Proceedings of the National Academy of Sciences reveals a possible survival benefit for simply being happy. For their research, Andrew Steptoe and Jane Wardle of University College London analyzed data from 3,853 participants aged 52 to 79 years in the English Longitudinal Study of Aging, a cohort of older men and women living in England. Positive affect was assessed by having the subjects rate their feelings of happiness or anxiety four times during the course of a day, a method that avoids reliance on the ability to recall past emotions. The participants were followed for five years, during which any deaths were ascertained. Positive affect among the participants was categorized as high, medium or low. Among those who rated themselves happiest, 3.6 died over follow-up, compared with 4.6 percent of the medium-rated group and 7.3 percent of those who rated themselves least happy. Those in the highest group had a 35 percent adjusted lower risk of dying compared with those who reported feeling least happy. Anxiety appeared to have little impact on survival. Although those with a higher positive affect reported better self-rated health and less depression, there were no significant differences in the incidence of serious diseases, alcohol intake, ethnicity, employment or education compared with those in the other groups. "Momentary positive affect may be causally related to survival, or may be a marker of underlying biological, behavioral, or temperamental factors, although reverse causality cannot be conclusively ruled out," the authors write. "The results endorse the value of assessing experienced affect, and the importance of evaluating interventions that promote happiness in older populations." |