What you expect is often what you get, and the placebo effect is at work! We have noted elsewhere that one possible account for the engagement of the placebo effect is the wish to ‘please the physician’, to be a ‘good patient’. According to this Stanford study, this might come as only a few positive words. “… When a health care provider offers a few encouraging words about their patient’s recovery time from an allergic reaction, symptoms are significantly reduced.”

Similarly expectations about the benefit of exercise can be seen to actually impact on life expectancy outcomes. In this study “the team looked at death rates. They used statistical models to account for other factors linked to death, such as age, chronic illnesses, and body mass index (BMI). Even accounting for these risk factors, those who saw themselves as less physically active were 71% more likely to die in the 21 years following the original survey.”