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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Best Fitness Regime For Weight Loss in the UK
Finding the best fitness regime for weight loss involves combining regular physical activity with dietary changes — and for eligible adults, prescription weight management options are also available in the UK. The most effective approach combines cardiovascular exercise, strength training, and sustainable lifestyle changes. However, evidence shows that for some people, adding prescription medication like GLP-1 injections alongside exercise and diet can significantly improve results. This guide covers proven fitness strategies, eligibility for medication support, and how to access NHS weight loss services.
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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.
Effective Fitness and Weight Loss Medication Options in the UK
A sustainable fitness regime for weight loss typically combines three elements: cardiovascular exercise (150 minutes moderate activity per week), strength training (2–3 sessions weekly), and dietary changes (500 kcal daily deficit for ~0.5 kg weekly loss). The NHS recommends losing weight at a rate of 0.5 to 1 kg per week for best results.
For eligible adults, prescription weight loss medication is now available in the UK:
- Mounjaro (tirzepatide) — once-weekly injection; clinical trials showed average weight loss of 15–21% body weight alongside diet and exercise
- Wegovy (semaglutide) — once-weekly GLP-1 injection; average weight loss approximately 15% body weight in trials
- Saxenda (liraglutide) — daily injection; also approved for weight management
These prescription medications may help reduce appetite and support fuller feelings after meals, making it easier to stick to your fitness and dietary goals. Individual results vary significantly.
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 Private Options for Weight Loss Support
In the UK, access to prescription weight loss medication differs between NHS and private routes. NHS access is through tier 3 specialist weight management services — your GP can refer you, though waiting lists vary significantly by region and availability can be limited. Private access is available through UK-licensed prescribers following an online clinical assessment; no NHS referral required.
Eligibility typically requires 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. Your GP can assess whether medication is suitable for you. Use our free GLP-1 weight loss calculator to estimate potential results, and our BMI calculator to check if you fall within typical eligibility ranges. Combining medication with regular fitness activity and healthy eating delivers the best outcomes.
- 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.
What is the best fitness routine for weight loss?
The most effective routine combines cardiovascular exercise (150 minutes weekly at moderate intensity), strength training (2–3 sessions weekly), and a 500 kcal daily calorie deficit through diet. The NHS recommends losing 0.5–1 kg per week. Consistency matters more than intensity — sustainable routines you can maintain long-term produce better results than crash approaches.
Can prescription weight loss medication replace exercise and diet?
No. Prescription medications like Mounjaro and Wegovy are designed to work alongside dietary changes and increased physical activity, not replace them. They may reduce appetite and support you in sticking to your fitness goals, but lifestyle changes remain essential. Clinical trials show best results when medication is combined with exercise and healthy eating.
Am I eligible for weight loss medication in the UK?
You may be eligible if you have a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes, high blood pressure, or sleep apnoea. For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, lower thresholds may apply. Your GP or a licensed prescriber can assess your individual eligibility.
What's the difference between NHS and private weight loss medication?
NHS access is through specialist tier 3 weight management services by GP referral; availability varies by region and waiting lists can be long. Private access is available through UK-licensed prescribers following online clinical assessment, without NHS referral. Both routes require a prescription and clinical assessment; costs and timeframes differ.
How much weight can I lose with prescription weight loss medication?
Clinical trials show average weight loss of 15–21% body weight with Mounjaro and approximately 15% with Wegovy over 12–18 months, alongside diet and exercise. However, individual results vary significantly — some people lose more, others less. Results depend on your starting weight, adherence, fitness regime, and dietary changes. Use our weight loss calculator for personalised estimates.
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.