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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Weight Loss Running Machine: UK Prescription Options
Running is excellent for weight management, but many UK adults find combining regular exercise with prescription medication more effective. If you're considering weight loss alongside a running routine, prescription options like Mounjaro and Wegovy may be available depending on your BMI and health profile. This guide explains UK-licensed weight loss medications, eligibility criteria, and how to discuss options with your GP or a licensed prescriber to support your fitness and weight management goals.
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Calculate Your BMI Instantly
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 Weight Loss Medications
Three prescription-only medications are licensed in the UK for weight management:
- Mounjaro (tirzepatide) — dual GIP and GLP-1 receptor agonist, once weekly injection. Clinical trials showed average weight loss of 15–21% of body weight over 72 weeks alongside reduced-calorie diet and increased physical activity.
- Wegovy (semaglutide) — GLP-1 receptor agonist, once weekly injection. Average weight loss of approximately 15% body weight in clinical trials at the maximum 2.4mg dose.
- Saxenda (liraglutide) — GLP-1 receptor agonist, daily injection. Approved for weight management in UK adults with BMI 30 or above, or 27–29.9 with weight-related health conditions.
All three work by reducing appetite, helping you feel fuller after smaller meals, and supporting sustainable weight loss. Individual results vary significantly. These medications are most effective when combined with a reduced-calorie diet and regular exercise—including running—not as replacements for lifestyle change.
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care — from a UK-regulated online pharmacy.
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 Access and Eligibility
In the UK, weight loss medication access is typically through NHS specialist tier 3 weight management services following GP referral, though waiting lists vary significantly by region (ICB). You may be eligible if:
- BMI is 30 or above, OR
- BMI is 27–29.9 with a weight-related health condition (type 2 diabetes, high blood pressure, sleep apnoea, or cardiovascular disease).
- Lower thresholds apply for South Asian, Chinese, Black African, or Black Caribbean adults due to higher health risks at lower BMI.
Alternatively, prescription weight loss medication is available privately through a licensed prescriber following an online clinical assessment. Your GP can advise which route is best for you and discuss combining medication with your running routine safely.
- 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 take weight loss medication if I run regularly?
Yes. In fact, combining GLP-1 or GIP/GLP-1 medication with regular exercise like running is recommended for best results. Always inform your prescriber about your exercise routine. They may adjust timing or offer hydration and nutrition guidance to support your running performance while on medication.
How quickly will I lose weight with medication and running?
NHS guidance recommends losing 0.5–1 kg per week for sustainable results. Clinical trials showed Mounjaro and Wegovy users lost 15–21% of body weight over 72 weeks alongside diet and exercise. Your individual results will depend on the dose, your baseline weight, diet quality, and exercise frequency.
What's the difference between Mounjaro and Wegovy for weight loss?
Mounjaro is a dual GIP and GLP-1 agonist (doses 2.5–15mg weekly), while Wegovy is a GLP-1 agonist only (doses up to 2.4mg weekly). Clinical trials suggest Mounjaro may produce slightly higher average weight loss, but results vary by individual. Your prescriber will recommend which is most suitable for you.
Do I need to change my running routine if I start weight loss medication?
Not necessarily, but discuss your exercise plan with your prescriber. You may need to adjust hydration, nutrition, or timing depending on side effects. Most people continue regular exercise alongside medication. Use MyWeightCheck's progress tracker to monitor your weight loss and running improvements together.
How do I find out if I'm eligible for NHS weight loss medication?
Start by calculating your BMI using the free BMI calculator on this page, then speak to your GP. They can assess your health profile, review weight-related conditions, and refer you to a specialist weight management service if appropriate. Private options are also available following an online clinical assessment with a licensed prescriber.
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.