The UK's most complete GLP-1 guide
Every Question Answered. Every Side Effect Explained.
- How GLP-1 medications work
- Mounjaro vs Wegovy compared
- Injection instructions
- Side effects & solutions
- What to eat on treatment
- FAQs answered
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Women's Fitness Programs for Weight Loss — Medication Options in the UK
Women's fitness programs work best when combined with evidence-based approaches to weight management. In the UK, prescription weight loss medications like Mounjaro and Wegovy are now available for eligible adults alongside exercise and lifestyle changes. This guide explains how prescription options fit into a comprehensive weight loss strategy, eligibility criteria, and how to discuss these options with your GP. Whether you're starting a new fitness routine or looking to enhance results, understanding all available support—including medication—helps you make informed decisions about your health.
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Enter your height and weight below. Supports both imperial (stone & lbs) and metric (kg). Results include NHS category, healthy weight range, and ethnicity adjustments.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is the most widely used screening tool for assessing whether your weight falls within a healthy range. Used by the NHS, GPs, and weight management services across the UK, BMI provides a quick snapshot of your weight relative to your height. The formula is simple: your weight in kilograms divided by your height in metres squared (kg/m²).
While BMI isn't a perfect measure — it doesn't account for muscle mass, bone density, or fat distribution — it remains the standard first step in identifying potential weight-related health risks including type 2 diabetes, cardiovascular disease, high blood pressure, and certain cancers.
The NHS also recommends adjusted thresholds for people of South Asian, Chinese, or Black African heritage — a BMI of 23 or above is classified as overweight, and 27.5 as obese. Our calculator includes this adjustment as a one-click toggle.
UK-Licensed Prescription Weight Loss Options for Women
If you're looking to combine fitness programs with additional support, three prescription-only weight loss medications are currently licensed in the UK:
- Mounjaro (tirzepatide) — a dual GIP and GLP-1 receptor agonist, injected once weekly. In clinical trials, women taking Mounjaro lost an average of 15–21% of their body weight alongside reduced-calorie diet and exercise.
- Wegovy (semaglutide) — a GLP-1 receptor agonist, injected once weekly. Clinical trials showed average weight loss of around 15% of body weight in women over 68 weeks.
- Saxenda (liraglutide) — a GLP-1 receptor agonist, injected daily. Produces slightly more modest weight loss than weekly injections.
All three medications work by reducing appetite and helping you feel fuller after smaller meals. They are not replacements for fitness programs—they work best alongside exercise, dietary changes, and lifestyle adjustments. Individual results vary significantly. Your GP or a licensed prescriber will assess whether you're eligible based on your BMI and health profile.
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How It Works
Three simple steps to understand your weight and take action.
Enter your height and weight in our free calculator. Get your BMI, NHS category, healthy weight range, and ethnicity-adjusted thresholds instantly.
If your BMI suggests you're overweight or obese, explore our GLP-1 calculators to project potential weight loss on Mounjaro or Wegovy.
Use our progress tracker to log your weight weekly, visualise your journey with charts, and stay motivated — all stored privately in your browser.
Free Weight Loss Tools & Guides
Everything you need to understand your weight, explore medication options, and track your progress — completely free.
NHS vs Private Access and Next Steps
In the UK, you can access prescription weight loss medication through two routes:
- NHS: Referral to a specialist tier 3 weight management service through your GP. Availability varies by region and waiting times can be lengthy in many areas.
- Private: Online consultation with a UK-licensed prescriber, followed by dispensing through a GPhC-registered pharmacy. Available without NHS referral.
To find out if you're eligible, calculate your BMI using our free BMI calculator above. Women with a BMI of 30 or above, or 27–29.9 with weight-related health conditions (such as type 2 diabetes, high blood pressure, or sleep apnoea), may be eligible. For those of South Asian, Chinese, Black African, or Black Caribbean heritage, lower BMI thresholds apply. Start by discussing weight management options with your GP—they can assess your individual circumstances and guide you toward the right approach for combining fitness with medical support.
- Dual GIP/GLP-1 receptor agonist
- Up to 22.5% body weight loss (SURMOUNT-1)
- Weekly injection, dose escalation over 20+ weeks
- Available via private prescription in the UK
- Doses: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
- GLP-1 receptor agonist
- Up to 15–17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg
Mounjaro vs Wegovy: Head-to-Head
A side-by-side comparison of the two most popular GLP-1 weight loss medications available in the UK.
| Feature | Mounjaro | Wegovy |
|---|---|---|
| Drug class | Dual GIP/GLP-1 agonist | GLP-1 agonist |
| Active ingredient | Tirzepatide | Semaglutide |
| Avg. weight loss | 15–22.5% | 12–17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20–32 weeks | 16–20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | £150–£250/month | £150–£300/month |
| Common side effects | Nausea, diarrhoea, constipation | Nausea, vomiting, diarrhoea |
Data sourced from SURMOUNT-1 and STEP 1 clinical trials. Costs are approximate and vary by provider. Always consult a prescriber.
Am I Eligible for Weight Loss Medication?
In the UK, eligibility for GLP-1 weight loss medications like Mounjaro and Wegovy is based on your BMI and overall health profile.
- BMI of 30 or above (obese)
- Age 18 or over
- No contraindicated conditions
- Committed to lifestyle changes
- BMI of 27 or above
- Plus type 2 diabetes
- Or high blood pressure
- Or obstructive sleep apnoea
Use our BMI calculator to check whether your BMI falls within the eligible range.
How We Built These Tools
Every calculator and guide on myweightcheck is built with accuracy and transparency in mind. Our BMI calculator uses the standard WHO formula with NHS-aligned category thresholds. Our GLP-1 projections are modelled on published clinical trial data from SURMOUNT and STEP studies.
All data stays on your device. We don't require sign-ups, and we don't store your health information on any server. Your progress tracker saves data locally in your browser using localStorage, so only you can see it.
We're based in the UK and our tools are designed specifically for UK users — supporting stone & lbs by default, referencing NHS guidelines, using NICE-approved medication data, and linking to GPhC-registered pharmacies.
Frequently Asked Questions
Common questions about BMI, weight loss medications, and our free UK tools.
Can I use prescription weight loss medication instead of exercise?
No. Prescription weight loss medications like Mounjaro and Wegovy are most effective when combined with fitness programs, dietary changes, and increased physical activity. They support your efforts—they don't replace them. The NHS recommends medication as part of a comprehensive weight management strategy, not as an alternative to lifestyle changes.
How do I know if I'm eligible for weight loss medication on the NHS?
You're potentially eligible if you have a BMI of 30 or above, or a BMI of 27–29.9 with weight-related health conditions. Lower thresholds apply if you're of South Asian, Chinese, Black African, or Black Caribbean heritage. Use our free BMI calculator to check your BMI, then discuss options with your GP, who can assess your individual health profile and refer you to specialist services if appropriate.
How long does it take to see results with weight loss medication?
Results vary between individuals. In clinical trials, most women saw noticeable weight loss within the first 8–12 weeks, with continued loss over several months. However, results depend on your starting weight, dose, adherence to the medication, and lifestyle changes. Your prescriber can discuss realistic timelines based on your circumstances.
What's the difference between Mounjaro and Wegovy?
Both are once-weekly injections but work differently. Mounjaro (tirzepatide) activates two hormone pathways (GIP and GLP-1), while Wegovy (semaglutide) activates one (GLP-1). In trials, Mounjaro produced slightly higher average weight loss (15–21%) compared to Wegovy (around 15%). Both require prescription and clinical assessment. Your prescriber can advise which suits your needs.
Can I track my progress while using weight loss medication?
Yes. Track your weight loss journey using our free progress tracker alongside your fitness routine. Monitoring progress—whether through measurements, weight, or fitness milestones—helps you stay motivated. Remember that weight loss is not always linear; some weeks you'll see progress, others less so. Your GP or prescriber can also monitor your health markers alongside weight loss.
Ready to take control of your weight loss journey?
Start with a free BMI check, explore your GLP-1 options, or begin tracking your progress today. No sign-up. No cost. Just results.