Fat-fighting jab fends off weight gain

7 August 2006

A new anti-obesity vaccine could help dieters stop piling on the pounds. The jab's just been through successful animal trials and its makers hope that in the future it could help fat-fighters eat as much as normal and still lose weight.

Antenna digs in...
Brain experts at the Scripps Research Institute in California have come up with a novel strategy for shedding excess flab. They've created a vaccine that joins forces with a dieter's own immune system.
The vaccine works just like a normal jab, but instead of telling your immune system to attack a disease molecule it targets a stomach hormone called ghrelin. This hormone is an appetite amplifier, but Scripps scientists think that it also slows down metabolism and encourages weight gain and fat build-up.
Drug co-developer Eric Zorrilla explains: 'Vaccinated rats gained less weight and became less fat, even though they ate the same amount of food. This suggests that they stored less of the food they ate as fat, probably because of the way ghrelin affects metabolic rates or fat storage.'

Eric Zorrilla, drug co-developer, Scripps Research Institute

But the jab won't be a quick fix - it will work best if combined with a controlled diet and exercise. It could make weight loss much easier though, and help dieters avoid other weight-loss drugs and their nasty side effects.
'The idea is that a dieting body thinks it is in "famine" mode and releases ghrelin to slow down metabolism, decrease fat burning and increase appetite,' says Zorrilla.
'We hope the vaccine can counter this response to perceived famine. It could mean an end to "yo-yo" dieting by blunting the regain that normally follows weight loss.'
But obesity expert Ian Macdonald, from the University of Nottingham, is cautious about the vaccine's potential: 'We now know there are many different hormones involved in regulating eating and there is no guarantee that interfering with one will do what we expect.
'A major aspect of preventing weight regain after weight loss will always be making sure people pay attention to what they are eating.'
Ian Macdonald, obesity expert, University of Nottingham
It will be several years before this vaccine is ready for testing on humans. But researchers in California may be one step closer to finding a reliable alternative to today's diet drugs.
.