The last weeks were very cold in Europe. Gradually it is getting warmer. Perfect conditions for catching a cold. What can you do in order to stay healthy? Eat fruit? Stay warm? Exercise? Might be beneficial. But something completely different might help: being optimistic.
In a study with students who were preparing for exams (and thus experiencing a stressful time), Claus Vögele from Roehampton University in London and his colleagues Heiko Schulz (Techniker Krankenkasse, German Health Insurance) and Björn Meyer (Medical Center Hamburg-Eppendorf) found that optimists suffered less from upper respiratory track infections than their pessimistic peers. This was the case during the exam preparation and after the exam. Thus, optimism is likely to protect from the adverse influence of heightened stress. The reason for this seems to be that optimists perceived the exam preparation as less stressful than the pessimists. The original study was published in the German Zeitschrift für Gesundheitspsychologie (abstract is available in English).
Optimism even seems to have an impact on longevity. In a longitudinal study, Matthias Bopp from the University of Zurich and his colleagues found that people who described their health condition as good lived longer than those who were more pessimistic about their health. Now one might argue that people who are in poor health will certainly judge their condition in a pessimistic way and die earlier, but not because of their pessimism, but because of their physical condition. However, the study was longitudinal, following the study participants during 30 years. The researchers controlled for risk factors like smoking, high blood pressure and chronic diseases. Matthias Bopp gives an example for this: Optimistic smokers live longer than pessimistic ones. He thinks that optimism builds up resources that are beneficial for getting old. The original study was published in the journal PLoS One.
These results are in line with the findings Sonja Lyubomirski from the University of California and her colleagues Laura King and Ed Diener report in their meta-analysis on the benefits of frequent positive affect. For example, optimists are less likely to suffer from a heart attack, live longer and have less mental health problems. Optimism seems to be beneficial for health and longevity! This means that when it is the season for colds, maintain a good diet, stay warm, and exercise. But also be optimistic!