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The nocebo effect – belief and biology – part III

by Jon Robison, Phd, MS

Decades of research on the placebo effect support that people’s perceptions and expectations about their health can positively influence physiological parameters as well as the course and outcome of treatment. But, is the opposite also true? Can negative expectations adversely affect our biology? The answer to this question is yes and the phenomenon is called the nocebo effect.

The word nocebo comes from the Latin nocere (to do harm) and is defined as “the causation of sickness or death by expectations of sickness and death and by associated emotional states.” People most commonly equate the nocebo effect with Voodoo, a concept well-documented in so-called “Traditional Societies” throughout the world. There is, however, substantial scientific evidence that the nocebo effect is alive and well in contemporary Western Cultures.  Here are a few examples from the research over the last 4 decades:

When individuals with asthma were told they were taking a drug that would make their breathing more difficult, airway resistance increased even though the drug was composed simply of saline solution.

People who were susceptible to poison ivy developed rashes when given a harmless look-alike plant and told it was the real thing

25% of people with food allergies developed symptoms when injected with a benign substance and told that it contained the foods to which they were allergic.

The suggestion that a mild electric current was being passed through the head of healthy volunteers caused headaches in about 2/3 of the people in spite of the fact that there was actually no electric current.

 A recent study in the journal Pain clearly demonstrates the power that people’s perceptions can have on their physiology. The authors reviewed 73 clinical trials from 1988 through 2007 involving comparison of the efficacy of 2 different anti-migraine medications (non-steroidal anti-inflammatories, and anticonvulsants) vs. sugar pills (placebos).  Non-steroidal anti-inflammatory drugs are known to cause stomach problems. Side effects from anticonvulsants include paresthesia (burning, itching, and numbness) and memory loss. In each study, participants were told they were going to be taking either one of the two drugs or a placebo. In all cases, people who were taking the placebo had side effects that were related to the drugs they thought they might be taking. No one who thought they might be taking an NSAID reported tingling or memory problems, and only people who thought they might be taking NSAIDS reported experiencing stomach problems.

Negative thoughts, feelings and expectations on the part of health care professionals can translate into potentially dangerous and even life threatening consequences for the people they are trying to help. In his excellent book, The Placebo Response, Dr. Howard Brody says that anytime a patient “feels less listened to, without a good explanation, uncared for, and less in control, then we’d predict that a nocebo effect is possible.” He goes on to say: “in our complex and often too impersonal health care system, nocebo effects must be rather common.”

In fact, the literature is replete with stories of individuals who appear to have suffered serious untoward consequences as a result of nocebo effects or what Dr. Andrew Weil refers to as medical “hexing.” In Spontaneous Healing, Dr Weil relates the story of a woman in her early 40’s who came to see him from Finland after being diagnosed with multiple sclerosis. Although the symptoms to that point had been limited to muscle weakness in one leg, she was depressed and related her story almost without emotion, as if it was all happening to someone else. It turns out that, as can be the case with this type of disease, the initial diagnosis had taken a long time to make and involved many tests. After finally sitting her down in his office and delivering the bad news, her neurologist excused himself and left the room only to return a moment later with a wheelchair that he invited her to sit in to “practice” for when she was totally disabled.

In a study at Massachusetts General Hospital, patients about to undergo surgery were randomly assigned to control and experimental groups that were matched for age, gender, underlying disease, severity of disease and type of operation. Those in the control group were addressed by anesthesiologists in a cursory manner. The anesthesiologist gave them his name and told them that he would be giving them the anesthesia the next day and that everything would be fine. The same anesthesiologists spoke warmly and sympathetically to those in the experimental group, sitting on the bed, holding the patients hand and discussing exactly what they should expect in the way of pain and suffering. The operations were performed the next day by surgeons and nurses who were not aware of which patient belonged to which group. The patients who experienced that simple 5-minute act of compassion needed only half the pain killing medication and were released from the hospital 2.6 days sooner than those in the other group!

Contrary to the traditional dogma of the separation of the mind from the body and of psychology from physiology, the literature on placebo and nocebo clearly demonstrates that thoughts, beliefs and emotions can powerfully affect our physical health. In all therapeutic encounters, treatment is delivered within a psychosocial context based on the expectations of the patient which is strongly influenced by her/his relationship with the involved provider. Every interaction has the potential to detract from or promote the healing process. Furthermore, the beliefs that people hold prior to entering into the therapeutic process can influence the outcome in either direction.

For the work that we do around size acceptance and weight and health, this information has particular significance. It helps us to begin to understand the devastating damage that can result from oppression, weight stigma, discrimination, marginalization, labeling, bullying, etc. even when they are done in the name of health. With the accumulated knowledge of the powerful effects that perceptions and expectations can have on our physiology it is time to realize that it is not only sticks and stones that can hurt us.

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