Are weight loss drugs really 'miracle' medicines?
8 min read
With new weight-loss drugs hailed as ‘miracle’ medicines, Harriet Symonds explores whether their increasing popularity should be treated with more caution
They seem too good to be true: a new generation of weight-loss drugs developed to treat type 2 diabetes are effective in achieving weight loss. These drugs could finally turn the tide on obesity, with potentially transformative outcomes for the health service and economy.
What’s more, the drugs may offer new treatments for other conditions, including dementia, heart disease and some cancers.
Wes Streeting, the new Health Secretary, secured extensive media coverage recently when he proposed that the new drugs could be routinely prescribed as part of efforts to get obese people off benefits and into work. The “jabs for jobs” headlines were inevitable.
But some parliamentarians worry that ‘wonder drugs’ like Ozempic, Wegovy and Mounjaro are not a public policy panacea – and they are calling for a wider debate about the consequences of their mass uptake.
Whoever’s advising him hasn’t really looked at what it means to be overweight
Ozempic and Wegovy are a class of new medication, semaglutide, while Mounjaro contains tirzepatide. Both work by mimicking the hormone GLP-1 that helps regulate blood sugar and curb appetite.
Obesity related illnesses cost the NHS £11bn a year and waiting lists for weight management services are routinely reaching three to five years. The government argues there is a clear economic and health case for ‘jabs for jobs’, making it easier for people to get back to work and reduce reliance on an already overstretched NHS.
But not everyone agrees with jabbing our way out of the obesity crisis without properly addressing what is making people sick in the first place.
“I was shocked,” one Labour MP says of Streeting’s plans. “Whoever’s advising him hasn’t really looked at what it means to be overweight; how complicated the issue can be. It’s not just because you’re eating too much, there are other factors that bring you to this situation.”
“If you’ve got depression, no self-confidence and you’re struggling to get up in the morning, you’re not suddenly going to have the wherewithal to feel like you can get dressed and go to a job and do your best,” says another Labour MP.
“There are lots of reasons people don’t have a job. It’s not just loads of fat people sitting around waiting to work and hoping to be skinny. That’s not how it works.”
The weight-loss drug Mounjaro, recently approved by the National Institute for Health and Care Excellence (Nice), will be rolled out to 250,000 severely obese NHS patients over the next three years. There is also a five-year clinical trial of the drug now underway in Greater Manchester to discover its effectiveness at weight loss and getting people back to work.
“I find it kind of depressing. This is about poor people who just want to get back to work. It’s like dishing out some drug to make that happen rather than looking at the conditions of worklessness and the depression that goes with it.
“The lack of opportunity, the inequalities of income, all the other stuff that surrounds it and that there’s something rather but just slightly unpleasant about it all,” says Baroness Boycott.
“Given the obesity crisis, I can see why the Health Secretary might reach for it, but I think it’s slightly short-sighted. It scares the bejesus out of me, actually, because you can see this becoming a long-term idea.”
Sceptics argue that, unless the drug is rolled out alongside mental health support, exercise and dietary advice, it only solves half the problem. “Just giving someone a shot abdicates some of the responsibility to lead a healthy lifestyle,” says one Labour MP.
But new data suggests obesity rates could now be in decline after stubbornly climbing for decades. In the US, rates of adult obesity fell by around two percentage points between 2020 and 2023, according to the FT. This shift coincides with the uptake in weight-loss drugs.
Demand for the drugs shows little sign of slowing down. Profits for rival manufacturers Novo Nordisk and Eli Lilly were up at the start of this year but have since slowed due to market competition, coupled with manufacturing costs to keep up with growing demand.
Still, sales of Mounjaro totalled $3.1bn for the third quarter of 2024, more than double what they were a year ago. Third-quarter sales for Wegovy were $2.5bn and $4.3bn for Ozempic.
Estimates indicate that the weight-loss drug market could grow as large as $130bn by the end of this decade.
There are plenty of politicians with first-hand experience of taking the drugs – and not all the reports are positive. Common side-effects of taking the drug include nausea, vomiting and extreme tiredness.
Former cabinet minister Nadine Dorries reported losing an incredible two stone in three months taking Mounjaro, but decided to come off it because she wasn’t “firing on all cylinders” and was suffering from “continuous burping, nightmares and stomach cramps”.
Boris Johnson said he tried Ozempic but stopped after several weeks as the injections started making him feel ill.
Coming off the drug is often a challenge for patients: with appetites rapidly returning, many struggle to keep the weight off. Former MP Andrea Jenkyns described taking a weight loss drug for five months, then stopping, only to have an “insatiable appetite” that left her ravenous. It led her to caution against long-term use of the injections.
Shadow justice secretary Robert Jenrick said he “didn’t particularly enjoy” the drug when he tried it for six weeks last year, and ultimately returned to traditional methods to keep the weight off.
“It’s not about being a size 10 or size 20, it’s about eating the right food and being healthy for your body,” insists a Labour MP. “It’s not a solution – you want people to have a lifelong change.”
Around 40 per cent of people in Wegovy trials lost muscle as well as fat, according to the Obesity Health Alliance (OHA), which presents a problem if patients fail to exercise while taking the drug.
“It seems to me that some people will stay on it for 10 years, 20 years, 30 years and God knows what that is going to do,” says Boycott.
While both Ozempic and Wegovy are not recommended for use beyond two years, the drug Mounjaro can be used indefinitely in certain situations.
One Labour MP describes rolling out the drug at pace, without knowledge of the long-term implications, as “very irresponsible”.
“To some degree it is a miracle drug. It can be extremely useful to help people shift the pounds, but if it becomes a dependency drug, that is a whole other ball game,” warns Boycott.
“My fear and many other people’s fear is that that’s exactly what will happen because the health service is in such a bind.”
One MP on the Health Committee says that in cases where patients are medically obese, taking the drug can be justified, but opposes the idea of using it to shed a few pounds.
And after years of work on an obesity strategy, long-term solutions to the obesity crisis must not be forgotten in favour of this new drug. “They are not a replacement for the need to prevent obesity in the first place. There is no such thing as a silver bullet for obesity,” says Alfie Slade of the OHA.
There are also concerns that uptake of these drugs could lead to a rise in eating disorders. “We are very concerned about the potential harm it could cause to people with eating disorders and also the risk of them developing,” says Tom Quinn from eating disorder charity Beat.
To access the drug, some users have gone to extreme lengths, such as fabricating their BMI, the charity claims. Online pharmacies are another route to the drug, where people have changed their weight and digitally altered their photo to appear larger.
“People will really try anything to restrict their weight,” says Quinn. “It’s pretty unarguable that people are getting hold of this drug that shouldn’t be.”
The side-effects of the drug – nausea and vomiting – may be a trigger too. The charity says people with existing disorders should not be allowed access to any weight-loss drugs at all:
“We want to make sure that there is proper screening in place to make sure that those that are vulnerable or already have an eating disorder shouldn’t get the drug.”
This would be difficult to police given the hidden nature of eating disorders, however. And with eating disorder services already struggling to cope, any increase in demand could push these services over the edge.
There are no calls for weight-loss drugs to be banned, given their potential, but there is a sense that they ought to be treated with more caution. “It has to be used very carefully and I’m worried that it’s not going to be,” says Boycott.
PoliticsHome Newsletters
Get the inside track on what MPs and Peers are talking about. Sign up to The House's morning email for the latest insight and reaction from Parliamentarians, policy-makers and organisations.