Obesity remains one of the most pressing, and preventable, health challenges of our time. The UK is one of a number of countries undoubtedly struggling with it.
Author
- Dan Baumgardt
Senior Lecturer, School of Physiology, Pharmacology and Neuroscience, University of Bristol
It affects nearly every organ system in the body, contributing to cardiovascular conditions like coronary heart disease; musculoskeletal issues such as osteoarthritis and gout; and even the development of certain cancers , including of the breast, uterus and colon. Its impact on mental health is also significant.
A few years ago, injectable weight-loss drugs entered clinical use and quickly captured public attention for their ability to promote rapid fat loss. Ozempic is available on the NHS, but only for managing type 2 diabetes. Wegovy is authorised for weight loss and cardiovascular risk reduction and is also available on the NHS, though access is currently limited to specialist weight management services.
Now, a new option has emerged: Mounjaro , which is approved for both type 2 diabetes and weight loss. This dual-purpose drug is now available on the NHS, offering another potential tool in the fight against obesity.
Demand is expected to be high . However, access will be limited at first, with strict eligibility criteria for NHS prescriptions.
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What is Mounjaro?
Mounjaro (tirzepatide) is a once weekly injectable medication designed to help control blood-sugar levels. It works by boosting the secretion and effects of insulin, improving glycaemic control in people with Type 2 diabetes . It also slows gastric emptying - the process by which food leaves the stomach - and enhances feelings of fullness by acting on the brain. This combined effect reduces appetite and helps support weight loss.
Compared to similar medications like Ozempic and Wegovy (both brand names for semaglutide), clinical trials found Mounjaro more effective, with some participants losing up to 20% of their body weight over a 72-week period.
Who is eligible for Mounjaro on the NHS?
The NHS has introduced specific criteria to prioritise patients most in need.
First, patients need a BMI of 40 or more (classified as morbid obesity). People from certain ethnic backgrounds, such as South Asian communities, may be eligible at a lower BMI due to higher clinical risk of health conditions.
Second, at least four obesity-related health conditions must be diagnosed, including type 2 diabetes, hypertension (high blood pressure), dyslipidaemia (abnormal cholesterol or triglyceride levels), cardiovascular disease and obstructive sleep apnoea. (Some of these conditions often occur together; for example, high blood pressure and cholesterol.)
Patients are encouraged to check their BMI and confirm their diagnoses before contacting a GP. This helps ensure appointments are used effectively and discussions remain focused.
While the current criteria are strict, there is optimism that eligibility will broaden in the coming years to include people with lower BMIs and fewer co-morbidities.
Not eligible? Don't despair
The NHS continues to offer a comprehensive weight-loss programme , tiered according to BMI and previous attempts at weight loss. Don't underestimate the value of group-based programmes or community referrals - when a healthcare professional refers a patient to a community-based health service for further care or support - many of which can be accessed via your GP.
These services, such as the NHS digital weight management programme , support both individuals and families and can be highly effective for sustainable fat loss.
GPs may also refer patients to online courses and structured exercise programmes. Lifestyle interventions, including increased physical activity and healthier eating, remain cornerstones of obesity treatment and are critical for long-term success, even when medications are used.
Higher tier interventions may be considered if lifestyle changes fail or if the patient has significant co-morbidities. This is where medications like Mounjaro, or private prescriptions, may become relevant - albeit that the cost of the latter may be a limiting factor for some.
Other treatments include Orlistat , a medication that reduces fat absorption in the gut. This can be effective for some but often causes unpleasant side effects , such as oily stools and gastrointestinal upset
Gastric banding or surgery may also result in significant, sustained weight loss, but they come with risks, can lead to surgical complications , and recovery can be demanding
It's also important to recognise that drugs like Mounjaro aren't suitable for everyone. They can cause side effects significant enough for people to stop using them, and in some cases, they may not work at all.
In this new era of faster, medication-assisted weight loss, we must remember that long-term change is about more than quick fixes. Sustainable success comes from consistent effort, willingness to change and methods that are both practical and lasting.
Medications can help , sometimes dramatically, but they're not the only answer. A return to basics, with tailored support and realistic goals, remains as relevant as ever.
So whether you qualify for Mounjaro, are trying lifestyle changes, or are exploring other options, remember this: the journey to better health is personal, gradual and worth it.
Dan Baumgardt does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
