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
How Does Green Tea Aid Weight Loss in the UK?
Green tea contains compounds like catechins and caffeine that may support modest weight loss when combined with a healthy diet and exercise. However, the effect is relatively small — typically 1–3 kg over several months. For adults looking for more substantial weight management support in the UK, prescription weight loss medications are available through the NHS or private prescribing. This guide explains both natural approaches and evidence-based prescription options.
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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 Prescription Weight Loss Medications for Effective Management
If you're interested in weight management in the UK, several prescription weight loss medications are available alongside lifestyle changes like improved diet and exercise. The main options are:
- Mounjaro (tirzepatide) — a once-weekly injection that acts as a dual GIP and GLP-1 agonist. Clinical trials showed average weight loss of 15–21% of body weight over 72 weeks.
- Wegovy (semaglutide) — a once-weekly GLP-1 injection. Clinical data demonstrated average weight loss of approximately 15% of body weight at the maintenance dose.
- Saxenda (liraglutide) — a once-daily GLP-1 injection, often used for longer-term weight management.
All three are prescription-only and require clinical assessment. Individual results vary significantly. Our GLP-1 weight loss calculator can help you estimate potential outcomes at different doses based on clinical trial data. 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 cardiovascular disease.
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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 in the UK
NHS access: Available through specialist tier 3 or tier 4 weight management services. Ask your GP for a referral — availability and waiting times vary significantly by region. Many areas have substantial waiting lists.
Private access: Available through GPhC-registered online pharmacies following an online clinical assessment with a UK-licensed prescriber. This route typically offers faster access without an NHS referral.
Your GP can advise which option is most suitable for you and assess whether prescription weight loss medication is appropriate based on your individual health. Use our BMI calculator to check your current BMI — this helps determine eligibility. Even modest weight loss of 5–10% can improve blood pressure, blood sugar control, and reduce cardiovascular risk.
- 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 green tea actually help with weight loss?
Green tea contains catechins and caffeine which may boost metabolism slightly and support fat burning, particularly when combined with exercise. However, the effect is modest — research suggests 1–3 kg loss over several months when used alongside a reduced-calorie diet. It's not a substitute for dietary changes or exercise. For more significant weight management support in the UK, prescription medications like Mounjaro or Wegovy are available for eligible adults.
What's the difference between green tea and prescription weight loss injections?
Green tea is a natural supplement with minor metabolic effects. Prescription weight loss medications like Mounjaro and Wegovy are licensed medicines that work on appetite and satiety hormones, delivering much stronger results — average 15–clinically studied weight loss in clinical trials. They require a prescription and clinical assessment. Both work best alongside lifestyle changes including diet and exercise.
How can I find out if I'm eligible for prescription weight loss medication in the UK?
You're typically 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. Use our free BMI calculator to check your current BMI. Speak to your GP about referral to specialist weight management services, or contact a private prescriber for an online assessment. Both require clinical evaluation of your individual health.
Is weight loss medication available on the NHS in the UK?
Yes — tirzepatide (Mounjaro) and semaglutide (Wegovy) are available through NHS specialist weight management services. However, access requires a GP referral and is subject to regional availability and waiting lists. Private prescription is an alternative option available without NHS referral. Ask your GP about local services or explore both pathways to find what suits you best.
Can I combine green tea with prescription weight loss medication?
There are no known interactions between green tea and prescription GLP-1 or GIP/GLP-1 medications. However, always discuss any supplements or dietary changes with your prescriber before combining them with weight loss medication. Your healthcare provider can advise what's safe and effective for your individual situation.
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.