In a perfect world, overweight people could take a pill to stay slim and continue to eat whatever they want.  But this is reality and for years health experts have delivered the same old message --  “stay away from fattening foods and exercise regularly.”  But as VOA's Melinda Smith reports, a new vaccine might provide some hope for those who need more than an extra helping of willpower.

At least one billion people around the world are considered overweight or obese. So, trimming the fat has become a global problem.  

The target of the vaccine is a hormone called ghrelin. It stimulates the body to gain weight and store fat by slowing down the metabolism.  That's a problem for dieters because, when the body is deprived, it responds by producing higher levels of the hormone. That makes it harder to keep the weight off.

Many overweight people, such as Della Moreno, know this syndrome all too well. It's called "yo-yo" dieting. "I work too hard here and nothing seems to work."

Kim Janda

Researchers at the Scripps Research Institute of La Jolla, California have developed an anti-obesity vaccine that works on mice.  The rodents injected with the vaccine ate the same kind of food as other mice, but showed an increase in energy. 

Dr. Kim Janda is the author of the study. "In a nutshell what the vaccine does is -- it slows weight gain.  It also impacts metabolism, in particular fat storage."

The mice had fewer food choices than most humans have. They ate a low-energy, low-fat, less-tasty food than what's commonly available to people.  The researchers are still not certain whether the vaccine against ghrelin would prevent the development of obesity in humans who prefer a high-fat Western style diet. 

So, until that time comes, the message remains the same, says Fabio Comana of the American Council on Exercise. "We've got to control what we eat. We've got to be physically active. And we also have to incorporate some sort of lifestyle and behavior modification into our daily lives."