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
Which Tea Is Good For Weight Loss — And What Really Works
While certain teas like green tea and oolong tea contain compounds that may support metabolism, the evidence for tea alone as a weight loss solution is modest. For adults struggling with weight management in the UK, prescription weight loss medication offers a more clinically proven approach. Whether you're exploring dietary options or considering medical support, understanding all available weight management pathways — including NHS-approved prescription options — can help you make an informed decision about the best approach for your individual health needs.
10,000+ calculations today · NHS-aligned thresholds · 100% free
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.
NHS-Approved Prescription Weight Loss Options in the UK
If you're exploring weight loss strategies, prescription medications offer evidence-based alternatives to dietary supplements. Three UK-licensed weight loss injections are available for eligible adults: Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide). These are GLP-1 and GIP/GLP-1 receptor agonists — medications that help regulate appetite and support feeling fuller after meals.
In clinical trials, Mounjaro helped participants lose an average of 15–21% of body weight, while Wegovy showed average weight loss of around 15%. These results were achieved alongside reduced-calorie diets and increased physical activity. To find out if you're eligible for prescription weight loss medication, check if you have a BMI of 30 or above, or 27 or above with weight-related health conditions like type 2 diabetes or high blood pressure.
- Mounjaro: dual GIP + GLP-1 agonist, once-weekly injection, doses 2.5–15 mg
- Wegovy: GLP-1 agonist, once-weekly injection, doses 0.25–2.4 mg
- Saxenda: GLP-1 agonist, daily injection, doses 0.6–3 mg
Try our free GLP-1 weight loss calculator to explore projected weight loss outcomes at different doses, and use our BMI calculator to check your personal BMI eligibility threshold.
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 Weight Loss Medication — NHS vs Private Routes
In the UK, you can access prescription weight loss medication through two routes. The NHS route involves asking your GP for a referral to a tier 3 specialist weight management service. Availability varies significantly by region and waiting lists can be long. The private route involves an online consultation with a UK-licensed prescriber, followed by prescription through a GPhC-registered pharmacy — no NHS referral needed. Your GP is the best starting point: they can assess your individual health, discuss eligibility, and advise on the most suitable option for you.
- Both routes require a clinical assessment before prescription
- Prescription medications work best alongside dietary changes and increased physical activity
- Individual results vary — consistent effort with lifestyle changes is essential
Use our free progress tracker to monitor your weight loss journey once you begin any weight management programme.
- 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.
Is green tea actually effective for weight loss?
Green tea contains catechins and caffeine that may modestly support metabolism, but the effect is small — typically associated with only 1–3 kg weight loss over several months. It can be part of a healthy routine but is not a weight loss solution on its own. For meaningful, clinically proven weight loss, prescription medications show significantly stronger evidence.
Can I get prescription weight loss medication on the NHS?
Yes. If you meet eligibility criteria (BMI 30+ or 27+ with weight-related health conditions), ask your GP for a referral to specialist weight management services. Availability and waiting times vary by region. Private online prescribing is also available without NHS referral.
How much weight can I expect to lose with prescription medication?
Clinical trials show average weight loss of 15–21% body weight with GLP-1 medications, achieved over several months alongside reduced-calorie diet and physical activity. However, individual results vary significantly — some people lose more, others less. Your prescriber can discuss realistic expectations.
What's the difference between Mounjaro and Wegovy for weight loss?
Mounjaro (tirzepatide) is a dual GIP + GLP-1 agonist showing slightly higher average weight loss (~15–21%) than Wegovy (semaglutide, a GLP-1 agonist only, ~15%). Both are once-weekly injections. Your GP or prescriber can advise which is more suitable for you based on your individual health.
Do I need to make lifestyle changes alongside weight loss medication?
Yes. All prescription weight loss medications work best when combined with a reduced-calorie diet and increased physical activity. Medication supports appetite regulation, but sustainable weight loss requires lifestyle commitment. Your GP or dietitian can help create a personalised plan.
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.