Weight Loss Medications – what you need to know
Written by Nutrition Student Freya Torkildsen, reviewed by Niamh Dunne (RNutr)
Introduction
Originally developed to treat Type 2 Diabetes, weight-loss medications such as Wegovy and Monjaro, known scientifically as Glucagon-like peptide-1 receptor agonists (GLP-1s), have become increasingly popular in recent years as treatments for people struggling to lose excess weight. Between 2024 and 2025, an estimated 1.6 million adults in the UK used GLP-1 medications to support weight loss (Pumper, 2025). GLP-1 medications are licensed in the UK for specific medical conditions, including Type 2 diabetes and obesity. But should you take this medication for weight loss and cosmetic purposes?
Maintaining a healthy weight, which supports overall health, is associated with a lower risk of developing numerous obesity related health conditions and cardiovascular disease, for example, heart failure. However, it’s not always as simple as eating less or moving more; for some people, weight-loss medications may be the safest or most accessible option.
As the use of GLP-1’s for weight-loss continues to grow, some questions remain: what are they and how do they work in the body? What are the potential benefits or risks associated with the drug? This blog explores the scientific mechanisms behind GLP-1 medications and the potential benefits and risks associated with the drugs.
What are GLP-1s and how do they work?
GLP-1 drugs work by mimicking one of the natural hormones released after eating, glucagon-like peptide-1 (Morgan, 2024). This hormone helps to reduce appetite, slow digestion, and supports stabilisation of blood sugar levels (Pumper, 2025). By mimicking this hormone, GLP-1s help patients to feel fuller for longer and improve the body’s response to insulin, which can support fat loss (Health 360, 2025; Morgan, 2024).
GLP-1’s are most often pre-filled injectables or in tablet form, taken once a week (Cleveland Clinic, 2023). In the UK, the typical prescribed treatment duration when being used for weight loss is limited to two years (Bolt Pharmacy, 2026).
As prescription only medications, GLP-1s should only be offered following an assessment from a healthcare professional. However, due to an increase in demand, the online market for the medications have increased, where some providers fail to carry out adequate assessments and others selling the medications illegally without a valid prescription.
Current trends indicate that less than 200,000 patients are accessing GLP-1s through prescription from the NHS, compared to over 1.4 million accessing them privately (Namboowa, 2025). This increase in private access highlights the importance of ensuring that these medications are accessed safely and from legitimate sources.
Before starting GLP-1 medications, it’s important to be well informed before accessing the medication as it’s common for unregulated sellers, for example from beauty salons or on social media, to offer the drug without any medical oversight. This is risky as people may be given fake or unsafe versions of the medication, or they may be given it despite having no clinical need for it. These situations can lead to serious health consequences, which is why proper medical guidance and prescriptions are non-negotiable before taking GLP-1s.
It’s important to note that these medications don’t switch off hunger; they simply make it easier to feel satisfied with less food. GLP-1s should be used as a catalyst for lifestyle change and therefore good nutrition alongside regular exercise is essential when seeking long term health benefits and preventing nutritional deficiencies (University of Cambridge, 2026).
Because these medications suppress appetite, some people may find it harder to consume enough food to meet their daily nutrient requirements. This makes it especially important to prioritise nutrient dense foods while maintaining good dietary habits alongside treatment. There is still some stigma around GLP-1 use due to the common notion that taking the medication is ‘the easy way out’ compared to traditional diet and exercise approaches to weight loss (Jensen et al., 2025). However, these drugs work by targeting biological pathways which affect appetite, satiety and blood glucose regulation, mechanisms which lifestyle changes can’t always target alone.
Additionally, exercise and dietary changes may not be the most accessible option for everyone, for example if someone has a physical disability or food allergies they may find they are unable to fully change their lifestyle, taking weight-loss medication to be the most effective option for achievable results.
Benefits of GLP-1s
GLP-1s are well established for their benefits for Type 2 Diabetes treatment and obesity; however, research has shown that their benefits expand beyond weight loss and blood sugar control. Studies have linked GLP-1s to reduced rates of heart failure, stroke, myocardial infarction, diabetic kidney disease, metabolic liver disease, osteoarthritis peripheral vascular disease, and obstructive sleep apnea (Gonzalez-Rellan and Drucker, 2025).
Alongside these clinical benefits, many people see improvements in confidence, ability to be physically active, and motivation to maintain a healthy lifestyle. These changes can make someone’s everyday life more accessible and empowering.
Risks associated with taking GLP-1s
While GLP-1s can be very effective, there are potential risks which are important to be aware of:
- Weight regain is common after ceasing treatment, with research suggesting that many individuals regain most, if not all, the weight they lost with GLP-1s within 1.5 to 2 years after stopping the medication (University of Oxford, 2026).
- Gastrointestinal side effects, including nausea, vomiting, diarrhea, and constipation, may affect 1 in 10 users. This can result in dehydration, which if severe, may lead to other serious health conditions such as kidney damage.
- Hypoglycemia or low blood sugar is a risk for non-diabetic patients using GLP-1s for weight loss.
- Serious but less common side effects of GLP-1s include acute gallstone disease, pancreatitis, and severe allergic reactions.
- Pregnancy-related risks are another important consideration. It is advised to avoid taking the drug during pregnancy – it’s important to discuss treatment with a healthcare professional if you are planning to conceive.
Alongside physical risks, some people may experience mental-health-related side effects such as increased body dissatisfaction, body dysmorphia, or development of an increased focus on food and weight, which can lead to disordered eating patterns. These side effects are not likely for everyone, but it’s important to consider in a culture where weight loss is often idealised.
Cost is another important consideration. For individuals accessing GLP-1s privately, treatment can be expensive, often exceeding those of maintaining a nutritious and balanced diet.
(GOV.UK, 2025)
GLP-1s have also been described as a ‘lifelong treatment’, mainly because weight regain is common once the medication is stopped (Celletti, Farrar, and De Regil, 2025). This reflects how the body is trying to return to its previous weight as appetite comes back.
Finally, it’s important to consider that the risks and benefits of GLP-1 medications can vary widely between individuals, and the research is still evolving. The long-term effects are still not fully confirmed yet as it is only recently that this weight loss drug has been accessible.
Precautions to take + key takeaways
Before starting the treatment, it’s important to consider your diet to maximise the benefits and minimise any risks. Nutrient-dense foods should be the focus especially those rich in protein and fibre. Protein helps to protect your body against muscle loss instead of fat loss, and fibre supports digestion and helps reduce constipation, another possible side effect of treatment.
Some supportive food choices include:
- Fruits and vegetables
- Lean proteins, such as fish, chicken or tofu
- Whole grains, such as oats or quinoa
Choose nutritious recipes
Staying hydrated is also important. Drinking plenty of fluids throughout treatment can help reduce risks of dehydration, especially if you are experiencing gastrointestinal side effects.
(Clinic, 2025)
Overall, GLPs can be an extremely helpful tool to make weight loss more accessible for those living with obesity or type 2 diabetes when paired with supportive habits, realistic expectations and guidance from a medical professional and ensuring you are aware of the risks involved in the treatment. It is important that you are only taking the medication to treat one of these issues, not just to lose weight for cosmetic purposes.
References
Bolt Pharmacy (2026). Do You Have to Take a GLP-1 Forever? UK Treatment Duration Guide – Bolt Pharmacy. [online] Boltpharmacy.co.uk. Available at: https://www.boltpharmacy.co.uk/guide/do-you-have-to-take-a-glp-1-forever [Accessed 21 June 2026].
Celletti, F., Farrar, J. and De Regil, L. (2025). World Health Organization Guideline on the Use and Indications of Glucagon-Like Peptide-1 Therapies for the Treatment of Obesity in Adults. JAMA. [online] doi:10.1001/jama.2025.24288.
Cleveland Clinic (2023). GLP-1 agonists. [online] Cleveland Clinic. Available at: https://my.clevelandclinic.org/health/treatments/13901-glp-1-agonists [Accessed 21 June 2026].
Clinic, C. (2025). GLP-1 Diet Guidance. [online] Cleveland Clinic. Available at: https://my.clevelandclinic.org/watch/glp-1-diet [Accessed 24 June 2026].
Gonzalez-Rellan, M.J. and Drucker, D.J. (2025). The expanding benefits of GLP-1 medicines. Cell Reports Medicine, [online] 6(7), p.102214. doi:10.1016/j.xcrm.2025.102214.
GOV.UK (2025). GLP-1 medicines for weight loss and diabetes: what you need to know. [online] GOV.UK. Available at: https://www.gov.uk/government/publications/glp-1-medicines-for-weight-loss-and-diabetes-what-you-need-to-know/glp-1-medicines-for-weight-loss-and-diabetes-what-you-need-to-know [Accessed 21 June 2026].
Health 360 (2025). Your friendly guide to GLP-1 weight loss: what works, what doesn’t and what’s next. [online] Intermountainhealthcare.org. Available at: https://intermountainhealthcare.org/blogs/article/your-friendly-guide-to-glp-1-weight-loss-what-works-what-doesnt-and-whats-next?ref=glp-1tribe.com [Accessed 21 June 2026].
Jensen, S.D., Gualano, B., Andreassen, P., Scagliusi, F.B., SturtzSreetharan, C. and Brewis, A. (2025). Beyond the prescription: Global observations on the social implications of GLP-1 receptor agonists for weight loss. PLOS Global Public Health, [online] 5(12), pp.e0005516-e0005516. doi:10.1371/journal.pgph.0005516.
Morgan, K.K. (2024). Mounjaro, Ozempic, Wegovy, Zepbound: What’s the Difference? [online] WebMD. Available at: https://www.webmd.com/obesity/mounjaro-ozempic-wegovy-zepbound-difference [Accessed 21 June 2026].
Namboowa, D. (2025). GLP-1 drugs on the NHS: Can and should we roll them out at scale? | The king’s fund. [online] The king’s fund. Available at: https://www.kingsfund.org.uk/insight-and-analysis/blogs/glp-1-drugs-nhs-should-roll-them-out-at-scale [Accessed 19 July 2026].
Pumper, C. (2025). How to activate GLP-1 naturally. [online] Osu.edu. Available at: https://health.osu.edu/wellness/exercise-and-nutrition/activiating-glp-1-naturally [Accessed 21 June 2026].
UCL (2026). 1.6 Million UK adults used weight loss drugs in past year. [online] UCL news. Available at: https://www.ucl.ac.uk/news/2026/jan/16-million-uk-adults-used-weight-loss-drugs-past-year [Accessed 18 July 2026].
University of Cambridge (2026). Lack of support for people on weight loss drugs leaves them vulnerable to nutritional deficiencies, say experts. [online] University of Cambridge. Available at: https://www.cam.ac.uk/research/news/lack-of-support-for-people-on-weight-loss-drugs-leaves-them-vulnerable-to-nutritional-deficiencies [Accessed 21 June 2026].
University of Oxford (2026). New study finds that stopping weight-loss drugs is linked to faster regain than ending diet programmes | university of Oxford. [online] Ox.ac.uk. Available at: https://www.ox.ac.uk/news/2026-01-08-new-study-finds-stopping-weight-loss-drugs-linked-faster-regain-ending-diet [Accessed 18 July 2026].