From the Radford Files archives:

There’s an interesting new twist in the quest to lose weight: fake gastric banding surgery. These patients want the benefit of the surgery—in which a band is placed around the stomach to prevent overeating—but don’t want the risk of complications (or the scars). The solution? Pay a hypnotist to convince them that they actually had the surgery so that their bodies would be fooled into eating less.

A piece on ABC News profiled a woman named Lindley, who “said she lost 70 pounds in the first five months after her $1,077 mock surgery and hypnosis sessions, and is pleased with the results—at the very least she gained confidence that she could lose weight. According to a representative from the Elite Clinic about 470 mock gastric banding procedures have been done to date with 70 percent of the clients achieving some weight loss. Hypnotists Martin and Marion Shirran started what’s called gastric mind band hypnosis process in Spain three years ago, but hypnotists on this side of the Atlantic were keen to start on the project too.”

If this all sounds somewhat dubious, it should. The hypnotists seem to be relying on the well-known placebo effect, in which a fake treatment can (temporarily and under limited circumstances) have a real effect on health. But the placebo effect only works if the patient believes it is effective.

Neither the placebo effect nor hypnosis can “convince the body” that it had undergone gastric banding surgery, chemotherapy, or anything else. The stomach does not have a mind of its own and can’t be convinced, bribed, or fooled into doing anything. Lindley knew full well that she had not in fact had the fake surgery; she requested and paid for the procedure. Trying to fool a stomach into eating less makes no more sense than trying to fool nearsighted eyes into thinking they don’t need corrective lenses.

So what accounts for the weight loss by Lindley and others who have undergone this procedure (assuming it’s true and not just promotional claims)? The patients were paying more attention to what foods they ate, and in what quantities. It’s as simple as that. Most people don’t pay a lot of attention to what they snack on, and when people are asked to begin keeping a record of what they eat, they tend to eat less and lose weight. If these patients can change their lifestyles, eating less and exercising more, then the weight loss will be permanent. Of course, they could have done it with or without hypnosis and the fake surgery.

This piece originally appeared in the Briefs Briefs column in the June 2010 Skeptical Briefs newsletter.

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