It may be the most effective anti-obesity drug yet – but even Wegovy is no ‘wonder cure’
In my 30 years as an obesity researcher, I’ve seen all kinds of “wonder cures” come and go. Some were withdrawn due to serious side-effects; most have had only a relatively modest effect on people’s body mass.
But now a new generation of medications has arrived, based on a better understanding of the biological underpinnings of obesity. While previous pharmaceutical treatments resulted in weight loss of 5-10%, clinical trials of this new wave of drugs are reporting initial weight loss of 15-20%. They work by suppressing appetite and slowing down digestion so we feel full for longer. One of these medications – semaglutide, sold under the brand name Wegovy – will soon be available in UK chemists in the form of a weekly, self-administered injection.
Social media users who have tried semaglutide (which is sold in the
US under the brand name Ozempic) rave that the drug instantly changed their relationship with food – “flicking a switch” to turn off their hunger and cravings. Elon Musk has used it, and rumours abound about that other celebrities have too. It sounds revolutionary, right? Potentially, yes – but only up to a point.
These drugs are so effective because they address one of the many complex causes of obesity. When we eat, our bodies usually release “satiety hormones” to make us feel full. But in people living with obesity this doesn’t always happen, which can result in uncontrolled hunger and a heightened responsiveness to food. Prolonged restriction of food – also known as dieting, something most people livingwith obesity will face pressure to do – can further weaken that satiety hormone response. Wegovy contains the satiety hormone GLP1, which steps in where the body’s hormones may have failed, boosting sensations of fullness, suppressing reward-driven eating and increasing feelings of control.
However, caution is needed. Semaglutide side-effects can include nausea, bloating, diarrhoea and wind, and close medical supervision is needed as the dose is increased over the first four weeks.
While there is no doubt that these drugs are an important tool in the management of obesity, they are only that – one tool. The drug fulfils a biological function, but it doesn’t provide