The Power of Placebo

An astonishing new twist to placebo research came in a 2010 pilot study led by Harvard’s Ted Kaptchuk, that showed that placebos worked even when people knew they were taking a placebo. In the study, Kaptchuk and his colleagues gave 40 patients with irritable bowel syndrome a placebo. Each patient received a bottle clearly labeled “placebo pills” and was told it contained “placebo pills made of an inert substance, like sugar pills, that have been shown in clinical studies to produce significant improvement in IBS symptoms through mind-body, self-healing processes.” A second group of 40 IBS patients, given no pills, served as a control group.

After three weeks, the group taking the placebos reported twice as much symptom relief as the no-treatment group—a difference that Kaptchuk noted is comparable to the performance of the best real IBS drugs. These patients hadn’t been tricked into healing themselves. They knew full well that they weren’t getting any medication—and yet after hearing the suggestion that the placebos could relieve their symptoms and believing in an outcome independent of the cause, their bodies were influenced to make it happen.

Meanwhile, a parallel track of studies that examines the effect of attitude, perceptions, and beliefs is leading the way in current mind-body research, showing that even something as seemingly concrete as the physical benefit of exercise can be affected by belief. A 2007 study at Harvard by psychologists Alia Crum and Ellen Langer involving 84 hotel maids is a perfect example.

At the start of the study, none of the maids knew that the routine work they performed in their jobs exceeded the Surgeon General’s recommendation for a healthy amount of daily exercise (30 minutes). In fact, 67 percent of the women told the researchers that they didn’t exercise regularly, and 37 percent said they didn’t get any exercise. After this initial assessment, Crum and Langer divided the maids into two groups. They explained to the first group how their activity related to the number of calories they burned and told the maids that just by doing their jobs, they got more than enough exercise. They didn’t give any such information to the second group (who worked in different hotels from the first group and so wouldn’t benefit from conversations with the other maids).

One month later, the researchers found that the first group lost an average of two pounds, lowered their percentage of body fat, and lowered their systolic blood pressure by an average of 10 points—even though they hadn’t performed any additional exercise outside of work or changed their eating habits in any way. The other group, doing the same job as the first, remained virtually unchanged.

This echoed similar research done earlier in Quebec, where a group of 48 young adults participated in a ten-week aerobic exercise program, attending three 90-minute exercise sessions per week. The group was divided into two. The instructors told the first half, the test subjects, that the study was specifically designed to improve both their aerobic capacity and their psychological well-being. They mentioned only the physical benefits of aerobics to the second half, who served as the control group. At the end of the ten weeks, the researchers found that both groups increased their aerobic capacity, but it was only the test subjects, not the controls, who also received a significant boost in self-esteem (a measure of well-being).

As these studies show, our awareness alone can have an important physical effect on our bodies and our health. What we learn, the language that’s used to define what we’ll experience, and how we assign meaning to the explanations that are offered all affect our intention—and when we put greater intention behind what we’re doing, we naturally get better results.

In short, the more you learn about the “what” and the “why,” the easier and more effective the “how” becomes.