A 5-foot-9, 22-year-old man who weighs only 101 pounds eats as much as 6,500 calories a day.

"I'm a medical mystery," said Matt Chaffee

Chaffee, who has a 26-inch waist, had several health problems as a newborn. One of them, pyloric stenosis, prevents food from emptying out of the stomach. The condition and ulcers he developed in his esophagus reduced his ability to gain weight.

His mother, Kelley Chaffee, told the Post Register that since turning 18 his goal has been to go over 100 pounds. He achieved that on a diet that included 5,000 calories a day in protein shakes.

Matt Chaffee is an Eastern Idaho Technical College student and WinCo Foods cashier who works out five days a week and can bench press 130 pounds.