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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Running Plan For Weight Loss — UK Prescription Options
Running is an excellent way to support weight loss, but for many UK adults, combining exercise with prescription weight management medication can help achieve better results. If you're considering a running plan for weight loss and want to explore all available options, prescription medications like Mounjaro and Wegovy are available through the NHS and private prescribing in the UK. This guide explains how weight loss injections work alongside your fitness routine and whether you might be eligible for treatment.
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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 Prescription Weight Loss Options
Three prescription medications are licensed in the UK specifically for weight management: Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide). Both Mounjaro and Wegovy are once-weekly injections, while Saxenda is a daily injection.
These GLP-1 medications (and Mounjaro's dual GIP/GLP-1 mechanism) work by helping reduce appetite and supporting feeling fuller after meals. Clinical trials showed that adults taking these medications while following a reduced-calorie diet and increasing physical activity like running experienced significant weight loss—Mounjaro users lost an average of 15–21% body weight, while Wegovy users lost approximately 15% on average.
Eligibility in the UK: You may qualify if your BMI is 30 or above, or 27 or above with weight-related health conditions like type 2 diabetes, high blood pressure, or sleep apnoea. For South Asian, Chinese, Black African, or Black Caribbean adults, lower BMI thresholds apply (27.5+). Try our free BMI calculator above to check where you stand, then speak to your GP about whether prescription weight loss medication is right for you.
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 vs Private Access in the UK
NHS access: Weight loss medications are available through specialist tier 3 and tier 4 weight management services. You'll need a referral from your GP, though availability and waiting times vary significantly by region. Some ICBs (Integrated Care Boards) have longer waiting lists than others.
Private access: You can access prescription weight loss treatment through a GPhC-registered online prescriber without an NHS referral. A clinical assessment is required to ensure the medication is suitable for you. Costs typically range from £129–£320 per month depending on the dose.
Whichever route you choose, prescription weight management works best when combined with lifestyle changes—including your running plan—and a reduced-calorie diet. Track your progress using our free progress tracker to monitor your weight loss journey alongside your fitness routine.
- 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 injections if I'm already running regularly?
Yes. Prescription weight loss medications like Mounjaro and Wegovy are designed to be used alongside lifestyle changes, including exercise. In fact, clinical trials showed best results when medication was combined with reduced-calorie diet and increased physical activity. Always tell your prescriber about your running routine.
How long does it take to see weight loss results with medication?
Most people begin noticing changes within 2–4 weeks, though individual responses vary. Doses are increased gradually over weeks to find your effective maintenance dose. Significant weight loss typically becomes visible over 3–6 months when combined with diet and exercise like running.
Will I need to keep running if I start taking weight loss medication?
Prescription medications work best alongside lifestyle changes. Running supports cardiovascular health, mental wellbeing, and sustainable weight maintenance. Many people find they can run more comfortably as their weight decreases—another benefit of combining medication with exercise.
What's the difference between Mounjaro and Wegovy for weight loss?
Both are prescription-only and once-weekly injections. Mounjaro (tirzepatide) is a dual GIP/GLP-1 agonist with slightly higher average weight loss (15–21%) compared to Wegovy's GLP-1 mechanism (approximately 15%). Your GP or prescriber will help determine which is more suitable based on your health profile.
How do I find out if I'm eligible for weight loss medication on the NHS?
Start by speaking to your GP. They can check your BMI using our free calculator above and assess whether you have weight-related health conditions. If eligible, they can refer you to your local specialist weight management service. Private online prescribers also offer eligibility assessments if you prefer that route. ```
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.