A new British study entitles “Smile — it might save your life” has found that people who are in a happy mood on the day of their annual flu jab develop stronger antibody defenses than patients who merely feel so-so. What’s more, they only have to feel happy on the day they received the vaccination and not the moment they’re given it, say the Nottingham University researchers according to the British Daily Mail newspaper. Scientists have previously fixated on the harm that negative emotions wreak on our bodies. They can significantly increase our risk of high blood pressure and cardiovascular disease. Positive moods have largely been ignored by comparison. But emerging evidence suggests that being positive-minded may boost our health in numerous ways. Kavita Vedhara, a professor of health psychology who led the Nottingham University study, had previously looked at how being stressed can damage our defenses, specifically people who were under significant stress from caring for loved ones. ‘We found that they fared worse than normal when given flu vaccines: they produced fewer flu antibodies,’ she says. Vaccines contain an inactive version of a virus that trains our immune systems to recognize the live virus and attack it. The more antibodies we produce, the more powerful our defense against infection becomes. Moreover, UK expert in psychoneuro-immunology Dr. Neil Harrison said that comedy could not only reduce inflammation, but also boost the immune system; referring to the relationship between emotion and our immune responses. ‘It is not fanciful to suggest that our emotions can influence our immune systems positively,’ says Dr. Harrison, head of the Psychoneuroimmunology Lab at Brighton & Sussex Medical School. ‘Research already shows that our emotional states can alter the activity of the vagus nerve, which links brain and body and is involved with many of the internal organs, as well as with our immune systems. ‘This shows that our emotional brains can alter the behavior of the immune system — and hopefully this can happen in a positive way to boost its response.’