WEIGHT-LOSS JABS COULD HAVE HIDDEN SIDE-EFFECT FOR MENOPAUSAL WOMEN

Menopausal women with a disease that weakens their bones are at risk of making it worse if they take weight-loss jabs, experts have warned.

Dr Jack Mosley, the son of the late broadcaster and health advocate Michael Mosley, sounded the alarm over drugs such as Wegovy, Mounjaro and Ozempic, saying they could have a hidden side-effect for women.

The treatments work by mimicking the body’s natural GLP-1 hormone, which increases insulin production, slows digestion, and reduces appetite.

Their spectacular results in clinical trials have led to a worldwide surge in demand, but rapid weight-loss could compound problems for menopausal women with osteoperosis, Dr Mosley said. The disease makes bones more fragile, making them more likely to break, even from a minor fall or bump.

Speaking on the latest episode of The Dr Louise Newson Podcast, Dr Mosley said: “We know one of the risks of GLP1-s is that a significant amount of the weight you lose is muscle or lean body mass… 25-40 per cent of the weight you lose is body mass. And a main component of that is muscle. And muscle is so important for longevity and living healthy independent life in later age.

“I do also have some concerns it could, in certain people who aren’t eating the right nutrition, it could actually potentially exacerbate things like osteoporosis in menopausal women.

“That period around menopause and perimenopause, your hormones completely change and the decline in oestrogen and testosterone and progesterone can have big effects on you, especially in body composition…muscle loss can accelerate and other things like osteoporosis. So we really need to approach them with knowledge and care.”

Dr Mosley said GLP-1 drugs were “powerful” and “not magic bullets” in the battle against obesity. Common side effects include nausea and diarrhoea, and some people have suffered serious side effects such as pancreatitis and allergic reactions.

Case of reducing bone density ‘not proven’

Dr Martin Whyte, associate professor of metabolic medicine at the University of Surrey, told The i Paper it was “not proven” that GLP-1s themselves reduce bone mineral density.

However, he added that rapid weight loss could affect bone health.

“In fact, some studies suggest these drugs may have protective effects on bone,” he said. “Major trials found no increased risk of fractures. However, a key complicating factor is that weight loss – regardless of the cause – can increase the risk of low bone density, especially when it occurs rapidly.

“This happens because weight loss reduces the mechanical load on bones and alters the hormonal signals that regulate bone maintenance. Regular exercise, by increasing mechanical load, can help counteract the effects of weight loss on bone health.”

Some 1.5 million Britons are now paying for weight loss jabs privately as the NHS struggles to roll out treatments for those who qualify.

They have been endorsed by various celebrities, with former tennis champion Serena Williams becoming the latest famous figure to do so in a new advertising campaign.

Dr Mosley raised particular concern about the lack of awareness regarding the risks associated with GLP-1s, adding: “People are not provided with information about these medications… They are very effective but a lot of people don’t understand the risks and rewards, the side effects and how to manage them.”

‘Powerful medical tools with clear benefits for some’

Stephen Lawrence, a GP and Associate Clinical Professor at the University of Warwick, said GLP-1 drugs were “powerful medical tools with clear benefits for some, but also real risks, especially muscle loss and potential nutritional problems, if used without lifestyle changes or medical oversight”.

He told The i Paper: “They are much more than magic bullets and should be approached thoughtfully, respecting both their potential and their limits.

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“Menopause is a time of significant metabolic change, and while GLP-1 medications and hormone therapy both have roles in managing weight and health for women in this phase, they are most effective and safest when used as part of a broader lifestyle plan that includes exercise and nutritional support.

“Individualised care and evidence-based medical advice should always guide choices around these medications.”

Professor Lawrence added that women accessing the drugs on the black market were at greater risk of harm.

Dr Mosley clarified that he was “not for or against” weight-loss jabs. “They can be really beneficial for certain people, who are living with obesity and have tried a lot of these other dietary options. It is very difficult for some people,” he said.

2025-09-03T05:42:02Z