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
Free tracker included with every download this week
Vinegar and Weight Loss — What Works in the UK
While vinegar is often promoted as a natural weight loss aid, the evidence for its effectiveness is limited. If you're looking for evidence-backed weight management support in the UK, prescription options like Mounjaro and Wegovy may be available to you. These medications are licensed for weight loss in the UK and are prescribed through NHS specialist services or private online consultations. Understanding what actually works — and what has clinical backing — is essential for sustainable weight management. Our free BMI calculator can help you check whether your current weight falls within a healthy range and whether prescription weight loss treatment might be appropriate for you.
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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
For adults seeking evidence-based weight management in the UK, three prescription medications are currently licensed: Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide). Unlike dietary supplements or vinegar, these are prescription-only medicines that require clinical assessment before use.
- Mounjaro — Once-weekly injection. GIP and GLP-1 receptor agonist. Clinical trials showed average weight loss of 15–21% of body weight.
- Wegovy — Once-weekly injection. GLP-1 receptor agonist only. Average weight loss approximately 15% of body weight in trials.
- Saxenda — Daily injection. GLP-1 receptor agonist. Available since 2015 in the UK.
All three are used alongside a reduced-calorie diet and increased physical activity. Individual results vary significantly — these figures are clinical trial averages, not assures. Weight loss medications work by helping regulate appetite and support feeling fuller after smaller meals. A prescriber will assess your personal eligibility, health history, and any contraindications before prescribing.
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
NHS access: Available through specialist tier 3 weight management services. You'll need a GP referral. Availability varies significantly across UK regions, and waiting times can be lengthy.
Private access: Available through GPhC-registered online pharmacies following an online clinical assessment with a UK-licensed prescriber. No GP referral needed, though costs typically range from £129–£320 per month depending on dose and provider.
Eligibility generally requires a BMI of 30 or above, or 27–29.9 with weight-related health conditions (type 2 diabetes, high blood pressure, or cardiovascular disease). Use our free weight loss calculator to explore projected outcomes at different doses, and our BMI calculator to check your current range. A conversation with your GP is always a good first step.
- 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.
Does vinegar actually help with weight loss?
Limited evidence supports vinegar for weight loss. While some small studies suggest modest appetite reduction or slightly improved blood sugar control, the effects are minimal. UK health authorities do not recommend vinegar as a weight loss treatment. For evidence-backed support, prescription medications or structured lifestyle programmes have stronger clinical backing.
What is the difference between Mounjaro and Wegovy for weight loss?
Mounjaro (tirzepatide) is a dual GIP and GLP-1 receptor agonist, while Wegovy (semaglutide) is a GLP-1 agonist only. Clinical trials showed Mounjaro may achieve slightly higher average weight loss (15–21% vs approximately 15% for Wegovy). Both are once-weekly injections. Individual results vary, and both require prescription and clinical assessment.
Am I eligible for prescription weight loss medication on the NHS?
Generally, you may be eligible if your BMI is 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes or high blood pressure. Eligibility can be lower (BMI 27.5+) for people of South Asian, Black African, Black Caribbean, or Chinese heritage. Your GP can assess you and refer you to a specialist tier 3 weight management service where medications may be prescribed.
How quickly can I get prescription weight loss treatment in the UK?
NHS waiting times for specialist weight management services vary significantly by region — some areas have waiting lists of several months or longer. Private online prescribing is typically faster, with assessment and prescription within days. Both routes require a clinical assessment before medication is supplied.
Do I need to change my diet and exercise if I use prescription weight loss medication?
Yes. Prescription weight loss medications are most effective when used alongside a reduced-calorie diet and increased physical activity. Medications help regulate appetite and support lifestyle changes, but they are not a substitute for diet and exercise. Your prescriber will discuss realistic goals and how to combine medication with sustainable behaviour changes.
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.