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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Hypnotherapy for Weight Loss in the UK
Hypnotherapy is a complementary therapy some people explore for weight management in the UK, though scientific evidence for its effectiveness remains limited. If you're interested in weight management support, it's worth knowing that evidence-based prescription options are also available for eligible adults in the UK. This guide explores hypnotherapy alongside medically-supported approaches to weight loss, helping you understand all your options for achieving a healthier weight.
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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.
Prescription Weight Loss Options in the UK
If you're interested in evidence-based weight management support, the UK has several prescription weight loss medications available. These are recommended for adults with a BMI of 30 or above, or 27 or above with weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea.
UK-licensed options include:
- Mounjaro (tirzepatide) — a once-weekly injection that acts as a dual GIP and GLP-1 receptor agonist. Clinical trials showed participants lost an average of 15–21% of their body weight over 72 weeks alongside diet and exercise.
- Wegovy (semaglutide) — a once-weekly GLP-1 injection. Evidence suggests average weight loss of around 15% of body weight in clinical trials.
- Saxenda (liraglutide) — a daily GLP-1 injection option, though less commonly prescribed than the once-weekly alternatives.
All three are prescription-only medicines requiring clinical assessment. A prescriber will evaluate your individual health profile to determine suitability. Use our GLP-1 weight loss calculator to explore potential outcomes at different doses.
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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 for Weight Loss Medication
NHS access: Prescription weight loss medications are available through specialist tier 3 and tier 4 weight management services. Speak to your GP about referral, though availability varies significantly by region and waiting times can be lengthy.
Private access: Available through GPhC-registered online prescribing services following an online clinical assessment. Faster access than NHS waiting lists, though costs range from approximately £129–£320 per month depending on medication and dose.
Your GP can discuss which route is most appropriate for you and help you understand eligibility. To check your current BMI and baseline health context, use our free BMI calculator above. Whichever approach you choose, weight loss medications work best alongside a reduced-calorie diet and increased physical activity.
- 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.
Is hypnotherapy effective for weight loss?
Research on hypnotherapy for weight loss shows mixed results. Some studies suggest modest benefit when combined with other weight management approaches, but evidence is not as strong as for lifestyle changes or prescription medications. Results vary considerably between individuals. Speak to your GP about all available weight loss options.
What prescription weight loss options are available on the NHS in the UK?
Mounjaro, Wegovy, and Saxenda are all available on the NHS through specialist weight management services. Access is typically via tier 3 services following GP referral. Availability depends on your local integrated care board (ICB). Your GP can discuss referral options and whether you're likely to be eligible.
How quickly do GLP-1 weight loss injections work?
Weight loss with GLP-1 medications typically begins within the first few weeks as doses are gradually increased. Most significant results are seen after 12–16 weeks of treatment at therapeutic doses. However, individual results vary substantially. Clinical trials show average weight loss of 15–21% over 72 weeks alongside diet and exercise changes.
Can I access prescription weight loss medication privately without waiting for the NHS?
Yes. Private GPhC-registered online prescribing services offer Mounjaro and Wegovy following a remote clinical assessment. This bypasses NHS waiting lists and is faster, though you'll pay privately (typically £129–£320 per month). Your prescriber will assess suitability based on your health profile.
How do I know if I'm eligible for weight loss medication?
You may be eligible if your BMI is 30 or above, or 27 or above with weight-related health conditions. Use our free BMI calculator above to check your personal BMI. Then speak to your GP about whether prescription medication is suitable for you, or explore private prescribing through an online assessment.
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.