Researchers say a new drug - found to cut body weight by up to 20% - is a "game changer" in the fight against obesity.

Semaglutide works by hijacking the body's own appetite regulating system in the brain, leading to reduced hunger.

The average weight loss in the study was almost 2-and-a-half stone.

But Professor Jill Pell, Director of the Institute of Health and Wellbeing at the University of Glasgow, thinks people should be given additional help to stay healthy.

"It's good to have a lot of tools in the armour, and in some people drugs and bariatric surgery are appropriate.

"However I don't think we should see it as a solution for the whole population gradually becoming obese - we can't rely on medications and surgery."