Hearing that your mood can affect your health is not new news. It has long been recognized that one’s emotional, psychological, and mental state can have an impact on your physical well-being. Laughing has been found to lower blood pressure. Laughing, according to one study, “is associated with a substantially reduced risk of heart attack and stroke” (How your attitudes affect your health: A positive view of life and aging may help you live longer. May, 2016, Harvard Health Publishing, Harvard Medical School). Depression and other mental health conditions have been found to contribute to heart disease and digestive issues (https://www.health.harvard.edu/topics/mind-and-mood). And chronic diseases are also affected. Patients with heart failure who are also depressed have a higher death rate than those who don’t have depression (https://www.health.harvard.edu/heart-health/your-emotions-and-your-heart).
Now there is evidence that if you’re in a good mood — happy, positive and upbeat — when you have your flu shot, your antibody response is better. In other words, a good mood has an impact on the efficacy of your vaccination. A recent study, “Positive mood on the day of influenza vaccination predicts vaccine effectiveness: A prospective observational cohort study,” published in Brain, Behavior, and Immunity (September 2017) tested the psycho-behavioral influences on the influenza vaccine. Although researchers were aware that behavioral and psychological factors can be “immune modulators” influencing vaccination outcomes, little was known about specific factors. This study found that the only factor that explained high response levels (i.e., greater antibodies) was a positive mood.
This result is especially important because influenza vaccinations are estimated to be effective only 17-53% in older adults. So when you get your flu shot this year, think happy thoughts! It makes a difference!