“It could be triggering for clients with eating disorders to see this approved,” said Deanna James, a spokeswoman for Castlewood Eating Disorder Treatment Center in St. Louis County.

Sullivan said the patients in the trial did not exhibit any bingeing or other abnormal eating behaviors, and in fact ate fewer calories because it takes longer to chew food into the desired consistency to aspirate it out of the stomach.

“Patients eat less. You have to chew food until it disintegrates. They have to chew so much they just get sick of chewing,” she said.

Candidates for the device cannot have a diagnosed eating disorder and should have a body mass index of 35 to 55, which is considered severe obesity. For a woman who is 5 feet 4 inches, that’s a range of about 205 to 320 pounds. In a 5-foot-10 inch tall man, it translates to 245 to 385 pounds. The average patient in the clinical trials went from a body mass index of 50 to 35 after the therapy, researchers said.

Eric Wilcoxon, 44, received the device in the clinical trial at Washington University in October 2013. At 6 feet 3 inches, he has gone from 389 pounds to his current weight of 270 and still uses the device three times daily.