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
Does Matcha Tea Help Weight Loss?
Matcha tea contains antioxidants and caffeine that some believe may support weight loss, but the evidence is modest. While matcha can be part of a healthy lifestyle, sustainable weight management in the UK typically requires calorie reduction and physical activity. For eligible adults, prescription weight loss medication offers a more clinically proven approach alongside lifestyle changes. Your GP can discuss whether medication 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 Prescription Weight Loss Options
If you're looking at weight management in the UK, prescription medications offer evidence-based support for eligible adults. The main UK-licensed options are:
- Mounjaro (tirzepatide) — a dual GIP and GLP-1 injection. Clinical trials showed an average weight loss of 15–21% of body weight over 72 weeks.
- Wegovy (semaglutide) — a GLP-1 injection. Evidence from trials demonstrated approximately 15% average weight loss.
- Saxenda (liraglutide) — a daily GLP-1 injection option.
You may be eligible if you have a BMI of 30 or above, or BMI 27–29.9 with weight-related health conditions like type 2 diabetes, high blood pressure, or sleep apnoea. Results vary by individual. These medications work alongside a reduced-calorie diet and increased physical activity — not instead of them. Try our free GLP-1 weight loss calculator to see potential outcomes at different 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.
NHS vs Private Access in the UK
NHS access is through specialist tier 3 weight management services. Your GP can refer you, though waiting lists vary significantly by region. Private access is available through GPhC-registered online prescribers following a clinical assessment — often quicker but at personal cost.
To find out if you're eligible, use our free BMI calculator to check your current BMI, then speak to your GP about your options. They can assess whether prescription medication is suitable based on your health history and weight management goals. Whether you choose matcha tea, dietary changes, or prescription support, sustainable weight loss requires consistency and professional guidance. Your GP is the best starting point for personalised weight management advice.
- 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 matcha tea actually help you lose weight?
Matcha contains caffeine and antioxidants (EGCG) that may slightly boost metabolism, but the effect is modest. Some studies suggest a small benefit for fat loss during exercise, but matcha alone won't cause significant weight loss. It's best viewed as part of a healthy lifestyle, not a weight loss solution.
What's the difference between Mounjaro and Wegovy for weight loss?
Both are GLP-1-type injections licensed for weight management in the UK. Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist; Wegovy (semaglutide) is GLP-1 only. Clinical trials showed similar average weight loss (15–21%), though individual results vary. Your prescriber will assess which is appropriate for you.
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. Eligibility varies by region and NHS service availability. Your GP can assess you and refer you to specialist services if appropriate.
How quickly do you lose weight on GLP-1 medication?
Weight loss typically begins within the first 4 weeks but is gradual. Most people see noticeable changes over 3–6 months. Clinical trials measured outcomes at 68–72 weeks. Individual results vary significantly. Medication works best alongside a reduced-calorie diet and physical activity.
Can I get Wegovy or Mounjaro privately if my GP won't refer me?
Yes. Prescription weight loss injections are available through GPhC-registered private prescribers following an online clinical assessment. This route doesn't require an NHS referral but involves personal cost. Always ensure the provider is legitimate and UK-licensed.
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.