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 Juice Cleanse Recipes and Prescription Alternatives
Juice cleanse recipes are widely promoted for weight loss, but evidence for their long-term effectiveness is limited. For sustainable weight management in the UK, prescription medications like Mounjaro and Wegovy offer clinically proven support alongside lifestyle changes. If you're interested in weight loss, it's worth understanding what prescription options are available, how they work, and whether you might be eligible through the NHS or private prescribing. This guide explains the UK landscape for evidence-based weight management.
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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
Three prescription medications are currently licensed in the UK for weight management:
- Mounjaro (tirzepatide) — a dual GIP and GLP-1 receptor agonist, once-weekly injection. Clinical trials showed average weight loss of 15–21% of body weight over 72 weeks when combined with diet and exercise changes.
- Wegovy (semaglutide) — a GLP-1 receptor agonist, once-weekly injection. Clinical evidence demonstrates average weight loss of around 15% of body weight at the highest dose.
- Saxenda (liraglutide) — a daily GLP-1 injection, less commonly prescribed in the UK than the weekly options.
Who is eligible: Adults with a BMI of 30 or above, or BMI of 27–29.9 with weight-related health conditions (type 2 diabetes, prediabetes, hypertension, sleep apnoea, cardiovascular disease). Lower BMI thresholds apply for South Asian, Chinese, Black African, and Black Caribbean adults due to increased health risks at lower weight. Use our free BMI calculator to check your personal BMI instantly, which your GP can use as a starting point for discussion.
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 vs Private Prescribing in the UK
NHS route: Referral to tier 3 specialist weight management services through your GP. NICE has approved these medications for NHS use, but availability varies significantly by region and waiting lists can be several months. You can ask your GP about local specialist services in your area.
Private route: Available through GPhC-registered online pharmacies following an online clinical assessment with a UK-licensed prescriber. This route does not require NHS referral and offers faster access, though you pay privately (typically £129–£320+ per month depending on dose). Either way, a prescriber will assess whether prescription weight management is suitable for your individual health.
Rather than relying on juice cleanses alone, which typically provide short-term results, prescription weight loss medication offers evidence-based support for sustainable change. Track your progress with our free progress tracker as you make lifestyle adjustments. Whether you choose NHS or private prescribing, the key is combining medication with reduced-calorie diet and increased physical activity—the approach used in all clinical trials. Start by having a conversation with your GP about weight management options available to you.
- 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.
Are juice cleanses effective for long-term weight loss?
Juice cleanses may cause short-term weight loss through calorie restriction, but evidence for sustained results is weak. Most people regain weight after stopping. Prescription weight loss medications like Mounjaro and Wegovy have stronger clinical evidence for maintaining weight loss when combined with lifestyle changes.
How do Mounjaro and Wegovy work for weight loss?
Both are GLP-1 receptor agonists (Mounjaro is dual GIP/GLP-1). They signal the brain to reduce appetite, help you feel fuller after smaller meals, and slow stomach emptying. Clinical trials show average weight loss of 15–21% of body weight at therapeutic doses over 12–18 months.
What's the difference between NHS and private weight loss medication in the UK?
NHS access requires GP referral to specialist services with potential waiting lists of months. Private prescribing via GPhC-registered pharmacies is faster but involves upfront cost. Both routes require clinical assessment and prescription from a UK-licensed prescriber.
Am I eligible for prescription weight loss medication on the NHS?
Generally, yes, if you have a BMI of 30 or above, or BMI of 27–29.9 with weight-related conditions like type 2 diabetes or hypertension. Use our free BMI calculator to check your BMI, then discuss eligibility with your GP.
Can I use juice cleanses alongside prescription weight loss medication?
Always discuss dietary changes with your prescriber. Most weight loss medication requires a balanced, reduced-calorie diet rather than restrictive cleanses. Very low-calorie diets without medical supervision are not recommended alongside these medications.
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.