Ultimate guide to weight-loss jabs: Top experts answer every question, from what REALLY happens to your body, the upsides and downsides, to how to pick the right one for you

They've been dubbed 'game-changers' in the world of obesity, making the seemingly impossible, possible – significant weight loss with minimal effort. 'Why this happens we don't know,' says Professor Miras, 'but if you haven't lost at least 5 per cent of your body weight after taking the full dose for three to six months, you'll probably need to change the treatment or look to other ways to lose weight.' In a study presented at the European Renal Association Conference in Sweden this year, patients with kidney disease taking semaglutide had a 24 per cent lower risk of needing dialysis or dying over the three-and-a-half-year trial – possibly due to its effect on inflammation..And the downside NAUSEA Around 30-40 per cent of people taking GLP-1 drugs experience nausea, says diabetes expert Dr Fareeha Rizvi – this may be because of their effect on brain areas that control appetite. HOW MUCH YOU MAY LOSE IN A YEAR: The average weight loss is 8 per cent of your body weight on the maximum dose. Another drug, retatrutide, is showing similar results, an average 24 per cent weight loss – but in just 24 weeks, reported the New England Journal of Medicine last year.