08/27/2007 at 01:00 AM EDT
The transformation happened so quickly. Nick Jonas, 14, the youngest member of the Jonas Brothers band—and the mildest-mannered of the family—began barking orders at his brothers like "Pizza. NOW!" That wasn't the only change: He began guzzling water, as many as 36 water bottles a day, and, in two weeks, lost 15 lbs. from his lean, 115-lb. frame. When he took his shirt off, "he looked like a prisoner of war," says his mom, Denise. "There was no muscle, just bones."
Why the drastic change? A simple blood sugar test cleared up the mystery. Nick has Type 1 diabetes. His body no longer produces insulin, the hormone needed to utilize sugar in the bloodstream for energy. Unlike Type II diabetes, more common in adults and often managed with diet, exercise and medication, Type I typically occurs first in kids and adolescents—roughly 1 in 500 has it—and requires daily insulin injections to maintain blood sugar within safe limits. Failure to keep that under control can quickly lead to serious problems. "If your blood sugar gets too low," says pediatric diabetes nurse Carolyn Gershenson, who has worked with Jonas, "you can become unconscious." If it stays high for too long, as Nick's was at the time of his diagnosis—700 milligrams per deciliter versus a normal premeal blood sugar count of between 70 and 120—you can fall into a coma.
At the time Jonas, then 13, had no idea what his diagnosis meant, except that it scared him. "Am I going to die?" he asked his doctor. The answer was no, but Jonas had a lot to learn. Coping with diabetes, a lifelong illness that puts one at increased risk for heart disease, blindness and kidney damage, can't be shrugged off or forgotten for an afternoon. "Knowing your child will have to think about this every day, at every meal, for the rest of his life, is overwhelming at times," says Jonas's father, Kevin, 42, a minister turned manager who never lets a rolling suitcase stocked with emergency supplies leave his side. "But if anyone can handle this, it's Nick."
Mature beyond his years—he appeared in four Broadway shows before the age of 10 and was signed to a record deal with his brothers by age 11—Nick admits it sometimes bothers him when people comment without thinking. Flight attendants, for example, will hassle him about drinking diet soda on planes—"They'll say you're thin enough," he says—although regular soda sends his blood sugar soaring. Before he switched to an insulin pump, he used syringes and pen injectors to give himself from 6 to 10 shots a day. "Once I was in the bathroom at a Fall Out Boy concert and some guy comes in, sees the syringe and goes, 'Cool!,'" recalls Nick. "He had no idea!"
Rather than hide it, Nick announced his condition to fans at a Diabetes Research Institute concert earlier this year, lifting up his shirtsleeve to show off his new pump, known as an OmniPod. The device attaches directly to the skin and drips insulin into the body. Before meals, Nick uses a remote control to increase the dose—based on blood sugar readings and how many carbs he intends to eat. "The only time you feel it is when you first put it on. It gives you a little prick, which is like a little needle," he says. "I want people to know I am not going to let this slow me down."
It doesn't seem to. Nick and his brothers Kevin, 19, and Joe, 18, are in the middle of a cross-country tour to promote their second album, Jonas Brothers, and appeared on the Disney Channel's Hannah Montana
with Miley Cyrus
, to whom Nick has been linked in real life. (He declines to comment, but Cyrus has called Jonas her boyfriend.) Home-schooled and wearing a "purity ring" on his finger to signify his commitment to sexual abstinence before marriage, Nick says he loves to hang out with his brothers, including Frankie, 6, the "Bonus Jonas." Oh, and he doesn't mind being a heartthrob. "It's any guy's dream," he says, "and the fact I am able to live it is awesome."
For more information on dealing with diabetes, go to DIABETES.ORG