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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Resistance Training and Weight Loss in the UK
Resistance training is one of the most effective ways to support weight loss, helping build muscle, increase metabolism, and improve body composition. But for many UK adults, combining exercise with prescription weight management medication can accelerate results. This guide explains how resistance training works with weight loss treatment options available in the UK, including NHS-funded and private routes to access Mounjaro, Wegovy, and other GLP-1 medications.
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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 Weight Loss Medication Options for Active Adults
Three prescription weight loss medications are currently licensed in the UK for adults who meet eligibility criteria:
- Mounjaro (tirzepatide) — A dual GIP and GLP-1 receptor agonist, administered once weekly. Clinical trials showed average weight loss of 15–21% of body weight over 72 weeks when combined with lifestyle changes, including exercise.
- Wegovy (semaglutide) — A GLP-1 receptor agonist, once-weekly injection. STEP trials demonstrated average weight loss of approximately 15% of body weight at the maximum dose (2.4 mg).
- Saxenda (liraglutide) — A GLP-1 agonist requiring daily injection. May support weight loss as part of a reduced-calorie diet and increased physical activity.
All three are prescription-only medicines. You may be eligible if your BMI is 30 or above, or 27–29.9 with weight-related health conditions such as type 2 diabetes, high blood pressure, or cardiovascular disease. Use our free GLP-1 weight loss calculator to explore potential outcomes at different doses, and our BMI calculator to check your current BMI in the context of NHS guidelines.
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 — How to Get Started
In the UK, prescription weight loss medication is available through two routes. NHS access is via specialist tier 3 or tier 4 weight management services, typically requiring a GP referral. Availability varies significantly by region and ICB (Integrated Care Board), and waiting lists can be substantial in many areas. Private access is through online consultations with UK-licensed prescribers, where a clinical assessment determines eligibility without needing an NHS referral.
Whichever route you choose, weight loss medication works best alongside resistance training and dietary changes. Start a conversation with your GP about whether prescription weight management treatment might be suitable for you, and consider tracking your progress with our free progress tracker to monitor both weight and fitness improvements over time.
- 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 weight loss injections if I do resistance training?
Yes. Weight loss medication like Mounjaro and Wegovy is designed to work alongside lifestyle changes, including exercise. Resistance training supports muscle retention during weight loss and improves body composition, making it an ideal complement to GLP-1 medication. Always discuss your exercise routine with your prescriber.
Which prescription weight loss medication is best with exercise?
Individual responses vary. Mounjaro (tirzepatide) showed slightly higher average weight loss in trials (15–21%) compared to Wegovy (approximately 15%), but both can support weight loss when combined with resistance training. Your prescriber will assess which is most suitable based on your health profile.
How long does it take to see weight loss results with medication and exercise?
Most people begin noticing changes within 4–8 weeks of starting Mounjaro or Wegovy, though individual timelines vary. Resistance training may show body composition improvements (increased muscle, decreased fat) before significant weight changes appear on the scale.
Do I need to be referred to the NHS to access weight loss medication?
Not necessarily. NHS access requires a GP referral to a specialist weight management service, which can involve waiting lists. Private online prescribing allows you to access these medications following an online clinical assessment without an NHS referral, though costs apply.
What BMI do I need to be eligible for weight loss medication in the UK?
You may be eligible if your BMI is 30 or above, or 27–29.9 with weight-related health conditions (diabetes, hypertension, cardiovascular disease). Use our free BMI calculator to check your current BMI and discuss eligibility with your GP or 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.