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Measuring the Placebo Effect

When Bonnie Anderson’s water purifier sprang a leak, she slipped on the wet tiles in her kitchen and cracked a bone in her spine. The 75-year-old, formerly an avid golfer, was crippled by pain and insomnia. In desperation, she volunteered for an experimental procedure called vertebroplasty, in which medical cement is pumped into the fracture. The treatment succeeded beyond all expectations: Bonnie walked out of the hospital and soon returned to the golf course. “Except,” as science journalist Jo Marchant writes in “Cure,” “there’s something Bonnie didn’t know when she took part in the trial: she wasn’t in the vertebroplasty group. The surgery she received was fake.” The operating team went through all the motions without actually injecting the cement.

Ms. Marchant’s “Cure” is a cautious, scrupulous investigation of how the brain can help heal our bodies. It is also an important look at the flip side of this coin, which is how brains damaged by stress may make bodies succumb to physical illness or accelerated aging.

The best known brain-body interaction in medicine is the placebo effect. Ms. Marchant documents some rather astonishing examples: In a laboratory on a cliff in the Alps, fake oxygen prevents an attack of altitude sickness; tremor and rigidity in a patient with Parkinson’s disease abate with a phony infusion of dopamine; an autistic child becomes more interactive after a sham medication. Some patients respond to placebos even when they know they are taking placebos.

The more drastic the placebo, the greater the response. Capsules are better than pills, injections trump capsules and placebo surgeries work best of all. The favored remedies of the 19th century, such as toxic doses of mercury and copious bloodletting by lancet and leech, were especially ferocious placebos, abetted by the plausibility and charisma of their practitioners.

Ms. Marchant cautions that placebos have limitations: “Any effects caused by belief in a treatment are limited to the natural tools that the body has available.” Fake oxygen can fool the brain into responding as if it had been exposed to real oxygen, but it cannot actually raise the levels of oxygen in the blood. In fact, the effects of placebos “tend to be limited to symptoms—things that we are consciously aware of, such as pain, itches, rashes or diarrhea.” According to Ms. Marchant, “placebo effects also seem to be particularly strong for psychiatric disorders such as depression, anxiety and addiction. In fact, they may be the main mode of action for many psychiatric drugs.”

One of the more intriguing chapters in “Cure” deals with fatigue. Ms. Marchant cites the English psychiatrist Peter White, who believes that tiredness is a purely mental phenomenon. Dr. White’s research suggests that graded exercise therapy can help the brains of some patients with chronic fatigue syndrome reset their fatigue threshold. This notion is more controversial than Ms. Marchant lets on; the methodology and validity of Dr. White’s work have been harshly criticize.

The opposite of the placebo effect is the nocebo effect. Injections hurt more when the patient is told to expect a little bee sting, compared with simply being told that the needle is going in. Similarly, patients have more side effects from a new medication when their doctor warns them that they may occur.

To minimize nocebo effects connected to medical and surgical procedures, Boston radiologist Elvira Lang has devised an approach that she calls Comfort Talk. Patients are warned of potential harms well in advance of the procedure, not immediately before. Staff soothe the patient, encouraging him or her to relax and focus on positive imagery. Dr. Lang has shown that Comfort Talk reduces claustrophobia in patients undergoing MRI, often eliminating the need for sedation and anesthesia. “It’s kind of crazy,” one radiology technician told Ms. Marchant, “but it really does work.”

Ms. Marchant travels to rural Georgia to investigate the relationship between income and well-being. As she writes, “there’s a linear health gradient through the entire socioeconomic spectrum.” This is especially true in the United States, where those in the top 10% of income live about 10 years longer than those in the bottom 10%. This effect holds up even after controlling for health behaviors such as alcohol, tobacco and drug use. Poverty and lack of control leads to chronic stress, which damages the cardiovascular system and hinders the immune system. Chronic stress even affects our ability to maintain the integrity of our chromosomes. According to Ms. Marchant, “feeling stressed doesn’t just make us ill. It ages us.”

In the last chapters of “Cure,” Ms. Marchant examines the possible benefits of a variety of stress-reduction techniques, including meditation and mindfulness training, compassion training, biofeedback, and a rewarding social life. She even travels to Lourdes to investigate the health effects of spirituality and religion. Regular churchgoers seem to live longer than non-churchgoers, an effect that may be mediated by stress reduction and stronger social networks rather than divine intervention. When it comes to health outcomes here on Earth, a God who is mild and forgiving might be preferable. As Ms. Marchant notes, belief in “an angry or judgmental God seems to make people more stressed, with subsequent effects on their health.”

Mainstream practitioners often regard alternative medicine as, at best, an outlet for patients such as Mrs. Renfrew in “Middlemarch,” for whom “the fullness of professional knowledge might need the supplement of quackery.” Conversely, patients may turn to alternative therapies because conventional physicians sometimes do a lousy job of providing attention and empathy. But “Cure” points a way toward a future in which the two camps might work together. After all, any medicine that makes a patient better, whether conventional, alternative, or placebo, is simply medicine.

By  JOHN J. ROSS

Dr. Ross, a physician, is the author of “ Shakespeare’s Tremor and Orwell’s Cough.”