Right now, miracle fat cure just isn't
CHICAGO -- Preliminary findings indicate the weight-regulating hormone leptin isn't the miracle fat cure some hoped it would be. Still, it shows some promise in helping achieve weight loss when combined with diet and exercise.
In the first trials on humans, some people lost as much as 35 pounds after six months of daily injections, with no serious side effects, while others lost no weight and some even got pudgier.
"It's a disappointment," said an outside expert, Dr. Roger Unger of the University of Texas Southwestern Medical Center in Dallas.
One of those involved in the study was slightly more enthusiastic.
"I'm guardedly optimistic," said Dr. Andrew Greenberg, who presented the findings yesterday at the American Diabetes Association's annual meeting in Chicago.
Though the first study did not involve diabetics, obesity is strongly linked to the disease.
Leptin is a protein produced by fat cells. It is supposed to signal the brain to stop eating, but the signal does not get through properly in some overweight people.
Scientists believe that most fat people produce high levels of leptin but their bodies are somehow resistant. By injecting synthetic leptin, they'd hoped to produce a response similar to what happens in adult-onset diabetics, whose bodies are resistant to the high levels of insulin they produce. Many do respond to injected insulin.
The study examined leptin's impact on obese subjects with a body mass index of 27.5 to 36, a measure of weight in relation to height. For example, someone who is 5-feet-10 and 207 pounds has a BMI of 30.
Subjects, mostly white males, were given either a placebo or a daily injection of synthetic leptin in varying doses. They were also placed on weight-reduction diets providing 500 calories less than their basic energy needs and were advised to exercise.
There were no significant adverse side effects, excluding mild to moderate skin reactions such as redness, itching or swelling at the injection site.
For subjects receiving the highest dose, the average weight loss was 16 pounds. Six of the eight people on the highest dose lost weight.
But overall, about 30 percent of those studied gained weight, including about half of the placebo subjects.