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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Weight Loss On Apple Cider Vinegar And Prescription Alternatives
Apple cider vinegar is often promoted for weight loss, but scientific evidence supporting significant weight loss is limited. If you're looking for evidence-based weight management support in the UK, prescription medications like Mounjaro and Wegovy have demonstrated meaningful results in clinical trials. These prescription options are available to eligible adults through the NHS or private prescribing, and are typically used alongside dietary changes and increased physical activity. This guide explains what the evidence actually shows and what evidence-based alternatives are available for weight management in the UK.
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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
If you're interested in weight loss support, several prescription medications licensed in the UK have strong clinical evidence behind them. These are available for eligible adults with a BMI of 30 or above, or 27 or above with weight-related health conditions.
- Mounjaro (tirzepatide) — A once-weekly injection that activates GIP and GLP-1 hormone pathways. Clinical trials showed participants lost an average of 15–21% of their body weight over 72 weeks, alongside lifestyle changes.
- Wegovy (semaglutide) — A once-weekly GLP-1 injection. The STEP trials demonstrated average weight loss of approximately 15% of body weight at the maximum dose.
- Saxenda (liraglutide) — A daily GLP-1 injection with established evidence for sustainable weight loss.
All three are prescription-only medicines requiring clinical assessment to determine suitability. Results vary individually, and these are used alongside reduced-calorie diet and increased physical activity. Use our free GLP-1 weight loss calculator above to explore potential outcomes at different medication doses.
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.
How To Access Prescription Weight Management In The UK
Access to prescription weight loss medication in the UK works in two ways. Through the NHS, you can speak to your GP about referral to a specialist tier 3 weight management service — though waiting lists vary significantly by region and availability is limited in some areas. Alternatively, private online prescribing is available through registered UK pharmacies following an online clinical assessment with a licensed prescriber.
Before starting any weight loss medication, your prescriber will assess your BMI, health history, and any existing conditions. Check your BMI using our free calculator above — this is the first step in understanding whether you might be eligible. Your GP can discuss which option is best suited to your circumstances and provide personalised weight management guidance.
- 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 apple cider vinegar actually help with weight loss?
Apple cider vinegar has limited scientific evidence for significant weight loss. Small studies suggest it may marginally improve satiety or glucose control, but effects are modest. For evidence-based weight loss support, prescription medications with clinical trial backing like Mounjaro and Wegovy are more reliable options.
What's the difference between Mounjaro and Wegovy?
Both are once-weekly injections for weight management. Mounjaro (tirzepatide) activates two hormone pathways (GIP and GLP-1) and showed average weight loss of 15–21% in trials. Wegovy (semaglutide) activates GLP-1 alone with approximately 15% average weight loss. Individual results vary — your prescriber will recommend the most suitable option.
Can I get prescription weight loss medication on the NHS?
Yes — you can ask your GP for referral to a specialist tier 3 weight management service. NHS eligibility and availability varies by region. Waiting times can be long in some areas. Alternatively, private online prescribing is available through registered UK pharmacies without NHS referral, though there is a cost.
Who is eligible for Mounjaro or Wegovy?
You may be eligible if you have a BMI of 30 or above, or 27 or above with a weight-related health condition (type 2 diabetes, hypertension, sleep apnoea, or cardiovascular disease history). Lower BMI thresholds apply for South Asian, Chinese, Black African, and Black Caribbean adults. A prescriber assesses individual suitability.
How much weight can I realistically expect to lose?
Clinical trials show average weight loss of 15–21% of body weight with prescription GLP-1 medications over 72 weeks, alongside reduced-calorie diet and exercise. Individual results vary significantly — some lose more, some less. Weight loss is gradual and sustainable, typically 0.5–1kg per week. Track your progress with our free progress tracker.
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.