This is the 2007 version. Click here for the 2017 chapter 09 table of contents.

Satiety Defects

The VMH rat shown on the previous page had a satiety defect. In other words, the normal mechanism that shuts off eating (food lingering in the stomach, producing a "full" feeling) was not working correctly. In humans, a complete breakdown of satiety regulation occurs in connection with a genetic disorder called the Prader-Willi syndrome. People with Prader-Willi syndrome simply do not stop eating, given a choice. They can die from overeating.

When her mother, Amanda Kavanaugh, went off to mass one recent Sunday, she forgot, despite years of practice, to padlock the refrigerator. When she returned, Helen (her daughter with Prader-Willi syndrome) had eaten the top two inches of a gallon pot of chicken soup, congealed fat included, four or five pudding pops from the freezer and several scoops of peanut butter. Mrs. Kavanaugh said Helen denied doing it.

What are symptoms of Prader-Willi syndrome?

Denial, deceit, connivance, stubbornness and temper tantrums in the face of rejected food demands are all traits of the syndrome, along with short stature, small hands and feet, incomplete sexual development, and mild retardation.

Typically, the victims do not realize how difficult they make life for their families. "It's hard for me," Helen said, with her unchanging smile, "but not for them."

But in reality, for the parents, all other aspects of life become subordinated to the unremitting battle with a child who may be 30 years old, weigh 300 pounds and be determined to eat. (Clendinen, 1985)

Television programs about morbidly obese individuals are now commonplace. A few titles from 2007 include I Eat 33,000 Calories a Day and World's Heaviest Man. A clinic specializing in morbid obesity (Brookhaven Clinic) has a series, and a surgical team specializing in stomach reduction has a series (Big Medicine). People featured on these programs are commonly in the 400-700 pound range. Remarkably, two of the topics most salient to weight loss are conspicuously absent from such programs.

What two topics seem to be missing from TV programs about morbidly obese people?

1. Techniques for monitoring calorie intake are seldom mentioned. The morbidly obese patients on the TV shows are interviewed and scenes from their daily life are shown, including meal scenes. However, they are never shown keeping records or punching data into a handheld device or in any other way keeping track of calories, the key variable in weight loss.

2. Satiety regulation is seldom if ever mentioned as such, although the shows often provide documentary evidence of satiety defects in their subjects. The morbidly obese do not get full as quickly as other people do. Some of them, including adults with Prader-Willi syndrome, say they never experience the sensation of fullness at all. So they keep eating.

It should be no surprise that ordinary diets fail, when a person lacks the mechanism that halts eating, and when calories are not being measured. The only treatments that work, given those limitations, are stomach-size reduction techniques, because they are the only treatments that physically prevent binge eating.

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