(CBS News) On Wednesday, the Food and Drug Administration approved the first new diet drug in more than a decade. America is fighting a so-far losing battle against obesity. More than 1 out of 3 adults -- 78-million -- are obese. Here is how this new drug works.
Fifteen years ago, Lisa Sutter started putting on weight. Then in 2007, she took part in a trial of the new diet drug Lorcaserin.
"Honestly it was like a switch was flipped in my brain," said Sutter. "The very first day I took it, I was able to stick to the number of calories that I was supposed to eat every day. I didn't feel an urge to overeat.
The drug, which will be marketed as Belviq, works by fooling the brain so patients feel fuller sooner. Sutter lost 40 pounds -- 20 percent of her body weight.
Most of the 8,000 patients in the trial didn't have the same results as Sutter. On average, those who took Belviq along with diet and exercise lost 5.8 percent of their body weight.
The drug was rejected in 2010 over concerns about tumors in animal studies and worry about damage to heart valves. On Wednesday, the FDA recommended patients who have congestive heart failure to use Belviq with caution.
Dr. Jeanmarie Perrone, who reviewed data on the drug for the FDA's advisory committee, still has her doubts about it.
"The benefit of the drug doesn't really outweigh the risks of the drug," she said, "in terms of the benefit being so modest in most of the patients who were exposed to it."
But for Sutter, the drug was life changing. She said, "Whatever went wrong 15 years ago in my body that started me on the path of gaining weight is fixed with this medicine."
After the trial, Lisa Sutter regained all the weight she had lost and now worries about developing diabetes. The latest tool in the difficult battle against obesity may be on the market by early next year.