A row has erupted over Britain’s booming use of weight-loss jabs, as experts clash over calls to prescribe the drugs for life – despite concerns over side effects, and dramatic weight regain when treatment stops.
The controversy follows a high-profile obesity conference in Venice, where experts claimed breakthrough research could justify keeping patients on anti-obesity drugs like Wegovy and Ozempic for life — comparing them to statins for cholesterol. This showed that patients on the drugs not only lost weight, but had a 20 percent reduced risk of heart attack or stroke.
Dr Simon Cork, an expert in obesity at Anglia Ruskin University said: “People with medical problems associated with obesity will need to take these drugs for life – just as a patient might take a blood pressure drug – because for most people, once you come off these drugs the weight goes back on.”
But last night critics hit back, warning that pushing powerful drugs for long-term use increases the risks of dangerous side effects and also masks the real issue — a national health system in crisis, failing to address diet, exercise and prevention.
Dr Adrian Heald, an expert in obesity at Manchester University said: “Obesity is not an illness. The notion of having a lifelong drug intervention given to a significant proportion of the population for something that is based on lifestyle has never been done before and is not evidence based.”
Professor Carl Heneghan, Director of Oxford University’s Centre of Evidence Based Medicine said: “These jabs are being handed out as a miracle fix, but they are not a long term solution. The longer someone is on them, the more chance there is of side effects which can include inflammation of the pancreas, kidney damage, and thyroid cancer as well as severe digestive problems. Given the rapid and widespread use of these drugs there are likely more side effects that have yet to be discovered and we do not know what happens when people are on them for decades.”
He added: “Two thirds of adults are now overweight or obese – level of unhealthiness in the population is unsustainable and there is not enough money to treat a population which is increasingly obese – including children. We need a radical new approach and we should not drift into mass medication without fully understanding the consequences.”
Recent data has shown most people put all their weight back on within a year of stopping the weight loss drugs – often faster than after dieting.
This research, led by Oxford University, found patients regained 13kg of the 16kg lost within 12 months of coming off the jab.
Critics say this proves the drugs are not a long-term solution, and should only be used alongside serious lifestyle support.
Sandra Roycroft-Davis, behavioural change specialist and author of ‘The Weight’s Over: Take Back Control, said: “Weight is never just about food — it’s about behaviour, emotion, and identity…most dieters self-sabotage their weight loss without even realising it. The moment someone stops the jabs — and they have to stop eventually — the weight begins to come back , because nothing has really changed. You’ve done the equivalent of putting on noise-cancelling headphones in a crowded room, the sound is still there when you take them off. The long term effectiveness of these drugs is uncertain. People’s health has to be the first priority.”
A spokeswoman for the National Obesity Alliance said: “We cannot outsource public health to a pharmaceutical company,” she added. “Obesity is a chronic, relapsing condition. It won’t vanish with a jab.”
And Baroness Jenkin, Chair of the All Party Parliamentary Group on Obesity said: “The food industry is making us ill but using the drugs industry to fix the problem will make people ill again due to side effects. We need a solution to prevent obesity in the first place.”
The row came after Britain’s drug regulator, the MHRA, issued an urgent alert to women of childbearing age following dozens of reports of unexpected pregnancies among patients on the jabs.
It believes the drugs may interfere with oral contraception by slowing digestion or may increase natural fertility – leading to pregnancies even while on the pill.
Alarmingly it also highlighted animal studies have linked semaglutide to miscarriages, birth defects and low birth weight, prompting its warning for women to stop treatment at least two months before trying to conceive.
Last week the Sunday Express unveiled research which showed up to 40 percent of the weight lost on the ‘fat jabs’ was muscle or bone, raising fears of an increased risk of deadly fractures, particularly in older people.
Up to 500,000 people are taking weight loss drugs in the UK – used by celebrities such as presenter Oprah Winfrey and businessman Elon Musk. Most – 95 percent – are buying the medication privately – sometimes through beauty salons or online pharmacies – so experts say for many the drugs may be doing more harm than good as they are not getting the right advice or support.
The government health regulator, the National Institute for Health and Care Excellence NICE, says weight loss injections should only be used for up to two years together with specialist weight management services, along with a reduced-calorie diet and increased physical activity, for adults with obesity and weight-related illnesses.
It states: “These medications are not a quick fix and should be used with ongoing support and monitoring.”