Fullness Hormone May Boost Weight Loss
Symlin, a Synthetic Version of the Hormone Amylin, May Curb Appetite
June 7, 2007 -- A fullness hormone called amylin may help obese people eat
less and lose weight without feeling hungry, a new study shows.
The study, published online in the American Journal of Physiology --
Endocrinology and Metabolism, focuses on a diabetes drug called Symlin.
Symlin is a synthetic version of the fullness hormone amylin.
The researchers included Steven Smith, MD, of the Pennington Biomedical
Research Center in Baton Rouge, La.
They studied 88 obese men and postmenopausal women. First, participants
weighed in and spent four days in a lab. During that time, they ate as much as
they wanted of prepared breakfasts, lunches, dinners, and snacks.
On the Menu
Most of the meals served at the lab were healthy and moderate in calories or
fat. Menu items included bagels, fruit, and cereal at breakfast; sandwiches and
cookies at lunch; a casserole and pudding at dinner; and
peanut-butter-and-jelly sandwiches as snacks.
However, one lunch was particularly fatty and sugary, featuring deep-dish
pizzas, ice cream, and soft drinks sweetened with high-fructose corn syrup.
Participants ate by themselves so they weren't influenced by what others
were eating. The researchers encouraged them to focus on their food and avoid
distractions, eating until they were comfortably full.
The researchers also weighed participants' servings and calculated their
Fullness Hormone Shots
During the first two days of the study, all participants got an inactive
shot (placebo) 15 minutes before each meal.
After that, the researchers switched some of the participants to Symlin
shots on the same dosing schedule.
When participants finished their four days at the lab, they went home with
instructions to inject themselves with Symlin or placebo 15 minutes before each
At home, participants were free to eat anything. They were told not to start
exercising or make any other lifestyle changes that might lead to weight
Using handheld electronic devices, participants rated their feelings of
fullness, hunger, and nausea. Finally, they returned to the lab at the end of
the six-week study for another meal of pizza and ice cream.
Throughout the study, participants didn't know whether they were taking
Symlin or the placebo.
During the study, participants in the Symlin group lost 4.5 pounds. Those in
the placebo group maintained their weight.
Both groups cut back on their daily calories. However, the Symlin group
trimmed more calories and didn't report more hunger than those in the placebo
Early in the study, the Symlin patients shaved 990 calories off their daily
calorie intake, while the placebo group cut 243 calories out of their daily
intake. That gap narrowed somewhat by the end of the study, but the Symlin
group still cut more calories than the placebo group.
Compared with the placebo group, the Symlin group was better able to resist
the final pizza-and-ice-cream meal at the end of the study than they had been
at the study's start.
Mild nausea was a common side effect in both groups, but that didn't explain
the Symlin group's weight loss, note the researchers.
One of the researchers, Christian Weyer, MD, is the executive director of
clinical research at Amylin Pharmaceuticals, which makes Symlin and funded the
The study appears online in the American Journal of Physiology --
Endocrinology and Metabolism.
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