- By James Gallagher
- Presenter of Inside Health, BBC Radio 4
You can’t escape the hype surrounding weight loss injections.
Social media is full of before and after pictures. They are the source of wild gossip about Hollywood stars and now the UK’s National Health Service will pay for them.
You can understand the appeal. Being overweight affects our health and carries a stigma – and the “diet and exercise” mantra has simply failed for most people.
But should we call semaglutide, the drug in question, a “miracle” or a “sleazy shot” when some doctors think it’s as controversial as the treatments? Does the advertisement match the reality? Or are we failing to address the causes of obesity and simply forcing people to take medication for life?
Ian, from Kent, was one of the first people in the world to take part in the semaglutide trials. It is sold as Wegovy for weight loss and as Ozempic for diabetes, although some people buy this version to lose weight.
We all know someone like Jan who has tried all kinds of diets and struggled with their waistline their whole life.
Semaglutide mimics a hormone that is released when we eat. It tricks the brain into thinking we are full and reduces appetite so we eat less.
After Jan began injecting herself, her relationship with food was so transformative that she told me it was either the drug or “I was abducted by aliens.”
For the first time, she could walk into a coffee shop, see a millionaire’s pastry and not have her body scream “I need it”.
Instead, it was, “I don’t feel hungry … my body was telling me you don’t want it, I wasn’t using my willpower,” she says.
The results of semaglutide are undeniable – at least for a while.
On average, obese people lost about 15% of their body weight when they took semaglutide along with healthy lifestyle advice in a study. Note that this is not a “weak hit” – 15% takes you from 20 stone to 17.
This study showed that weight decreased during the first year and then stabilized during the remaining three months of the trial. We don’t know what happens when people take the drug for years.
Jan lost 28kg (more than four stone). It meant she could finally enjoy her 60th birthday present of a Tiger Moth flight after previously being over the weight limit. “I’ve flown in more ways than one and I’ve really enjoyed it.”
The results seem more convincing than your typical diet, which often starts well, but then your depleted fat stores signal the brain to look for food. This is why diets ultimately fail.
“More than 90% of people tend to return to the weight they were before they started their diet journey,” says Prof Sir Stephen O’Rahilly, director of the Metabolic Diseases Unit at the Medical Research Council.
He sees these drugs as “the beginning of an exciting era” in which drugs can help people who “struggle for a long time” with weight that is damaging their health.
Jan’s trial ended and she could no longer take semaglutide. Without the drug, her brain was no longer tricked into thinking she was full.
“I was pretty upset because the weight was coming back,” she told me — and she was “promising the world” to anyone who could give her the drug.
She tried other weight loss injections, but ultimately opted for major surgery and a gastric sleeve to reduce the size of her stomach so she would feel full faster.
Jan has “no regrets” and still describes the drug as “the best thing that ever happened to me”.
The weight is coming back
However, her experience is far from unique, and weight gain after stopping semaglutide is rapid. The best long-term data we have shows that people regain two-thirds of the weight they lost within two years of stopping.
“It’s a drug that seems to have to be kept on to make sure the weight doesn’t come back, and that’s a big problem for me,” says Dr Margaret McCartney, GP and advocate for evidence in medicine .
The NHS only offers semaglutide for two years, which is how long people can access weight loss clinics. Given the weight gain after stopping the drug, it’s fair to ask – what’s the point?
“It’s really quite terrible for a lot of people who want to lose weight and have usually struggled for years. If you get something that ends up working for you and then the NHS goes and withdraws it again, it really seems to me to be a bit unfair,” says Dr McCartney.
There are, of course, circumstances where temporary weight loss can be beneficial. Some operations and treatments are only available to people below a certain threshold, for example.
This is a new drug and long-term safety is unknown. Side effects include vomiting, fatigue, and an inflamed pancreas.
Medical victory or societal failure?
Personally, I can’t figure out whether we should be celebrating that medicine has created such a drug, or whether it’s actually the opposite—that we’ve failed so badly to deal with obesity in society as a whole that we now need drugs.
“Many of us struggle with this,” says Naveed Sattar, professor of metabolic medicine at the University of Glasgow.
He is on the side of pragmatism. Half the planet is predicted to be overweight or obese by 2035, and obesity is linked to type 2 diabetes, heart disease and some cancers. Cheap calories have “entered the human biology of food temptation and overeating,” he says.
And many NHS patients “have four or five diseases as a result of being overweight and we’re paying lip service to that at the moment”, he says.
Dr McCartney argues that we need to address how the world we live in fuels obesity, rather than “waiting” for people to gain weight “and then accepting medical intervention to treat it”.
Professor O’Rahilly says that even if we address the societal causes of obesity, “there will be obese people and they will get sick”, so he believes drugs will move us into a world of treating obesity “properly as a medical condition”. .
But these drugs remain controversial—and we’ve only discussed their health-enhancing uses.
Further concerns are raised about the impact on people, often young women, who are pressured to look a certain way when ‘beautiful’ is often equated with ‘thin’.
The role of celebrity culture, the availability of semaglutide privately through online consultations, and the impact on eating disorders also fuel questions.
Whatever you think of semaglutide, the debate surrounding this drug and the hype is clearly not going to go away.