There is a vaccine that Scripps Research Institute in California researchers are working with that shows positive results in slowing down a key hunger hormone that keeps rats from gaining weight regardless of how much the rats ate -- although they caution that just because it works in rats does not mean it will work the same way in humans or that it will be a safe vaccine for humans.

This is all relatively new science, as the hormone, called Ghrelin, the researchers are testing the vaccine on was just discovered about seven years ago. The researchers do know that the hormone controls appetite in animals and humans and the current research might prove valuable in discovering more about the connections between hunger and weight gain; how the body stores fat and how to influence the hunger hormone.

At this point in time, if you are a rat concerned about controlling your weight, it's good news. Long-term, if it does show the same benefit for humans, the researchers speculate a vaccine might be developed that helps people who struggle with weight gain and loss maintain a steady and healthy weight. You know it is only a matter of time before they discover and develop something along this line, as obesity is a major threat to health for a number of diseases including cancer.