As with all diets, there comes a point where you stop losing weight – and you plateau. With weight-loss drugs, this usually occurs around 72 weeks of starting them, says Dr Foteini Kavvoura, a consultant endocrinologist at the Royal Berkshire NHS Foundation Trust.
The body has achieved a new metabolic ‘set point’, explains Dr Mamta Joshi, an endocrinologist at Epsom and St Helier University Hospitals NHS Trust.
‘It’s at this point that people often come off the drugs, thinking they’ve lost the weight they need to and that drugs are no longer helping them lose more weight and thus are not necessary,’ explains Carel Le Roux, a professor of metabolic medicine at Ulster University.
‘However, the main problem with diets is that once people stop doing them, they tend to regain weight – and weight-loss drugs are no different.’
In an analysis of studies on both old and new GLP-1 medications earlier this year, researchers at the University of Oxford found that patients typically lost 1st 3lbs (8kg) on weight-loss medication but returned to their original weight within ten months of stopping them.
There are some people who have dramatically changed their lifestyle through diet and exercise and manage to keep the weight off, but this is only around 2 to 5 per cent of people.
For everyone else, the weight-loss drugs are nothing more than brakes on the appetite centre and once they’ve been removed a decent amount of weight will return if alternative strategies are not put in place, says Dr Joshi.
‘Microdosing’ – taking smaller doses of the medications than prescribed – has become increasingly popular, particularly in the US, where the cost of the new GLP-1 drugs is much higher than in the UK
So why can’t I stay on them for ever?
On the NHS, semaglutide (Wegovy) is prescribed for a maximum of two years only for weight loss; this is based on Nice recommendations and certainly due to cost implications, says Dr Joshi.
This two-year cap currently doesn’t apply to Mounjaro, but guidelines may change as data evolves. Privately, these drugs aren’t bound by these restrictions.
‘In coming years, if we are able to demonstrate no significant increase in risk of pancreatitis events and thyroid cancer then it’s likely we’ll be more relaxed about using GLP-1 drugs for longer periods,’ adds Dr Joshi.
Can I microdose to save money and reduce side effects?
‘Microdosing’ – taking smaller doses of the medications than prescribed – has become increasingly popular, particularly in the US, where the cost of the new GLP-1 drugs is much higher than in the UK.
‘The main reason people do it is to save money, although some do it to lessen side effects,’ says Professor Alex Miras of Ulster University.
Others are also doing it to take that edge off hunger pangs and to lose smaller amounts – 11lbs (5kg) to 1st 8lbs (10kg) – of weight, too.
Essentially when you administer the jab you first attach the needle to a ‘pen’ cartridge containing the drug – you then turn the dose knob on the pen to obtain the amount (viewable in the dose counter window). With microdosing you would turn the knob fewer times to administer 1mg instead of a standard starting dose of 2.5mg. Or you would inject less frequently than advised, so every two weeks instead of every week, explains Professor Miras.
However, using the drugs this way is off-label, meaning different from its intended use.
‘While it’s generally safe and already practised in some private clinics in the UK – there have been no clinical trials that have tried it in real patients,’ he adds.
‘Microdosing for reduced side effects such as nausea does make some sense but shouldn’t be necessary on the lowest starting doses – and for losing weight, we know from the research that it’s dose dependent; the higher the dose the higher the weight loss with all the medications.
‘It makes no sense to take lower doses because you will lose less weight. It is as simple as that.’
[Notigroup Newsroom in collaboration with other media outlets, with information from the following sources]
