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
Teas for Detox and Weight Loss — What Works in the UK
Herbal teas are popular for supporting wellness, but their weight loss effects are modest. If you're looking for evidence-backed weight loss solutions in the UK, prescription medications like Mounjaro and Wegovy offer significantly stronger clinical results. This guide explores both approaches and explains what NHS weight loss options are available to eligible adults. We'll also help you determine whether prescription weight management might be right 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 — Stronger Clinical Evidence
If detox teas haven't delivered the results you're seeking, prescription weight loss medication offers clinically proven alternatives available in the UK. The main options are:
- Mounjaro (tirzepatide) — A dual GIP and GLP-1 injection. Clinical trials showed participants lost an average of 15–21% of their body weight over 72 weeks, alongside a reduced-calorie diet and increased physical activity.
- Wegovy (semaglutide) — A GLP-1 injection approved for weight management. STEP trials demonstrated average weight loss of around 15% of body weight at the maximum dose.
- Saxenda (liraglutide) — A daily GLP-1 injection alternative, though less commonly prescribed than the weekly options.
Unlike detox teas, these are prescription-only medicines requiring clinical assessment. Individual results vary significantly, and medication is always used alongside lifestyle changes—diet and physical activity remain essential. Your GP or a licensed prescriber will assess whether you're eligible based on your BMI and health profile.
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 — How to Find Out If You Qualify
In the UK, weight loss medication is available through two routes. NHS access is through specialist tier 3 weight management services—you'll need a referral from your GP, though waiting lists vary significantly by region. Private access is available through online consultations with UK-licensed prescribers, without requiring NHS referral.
To check your eligibility, use our free BMI calculator above. You generally qualify if your BMI is 30 or above, or 27 or above with weight-related health conditions like diabetes, high blood pressure, or sleep apnoea. For South Asian, Chinese, Black African, or Black Caribbean adults, slightly lower thresholds apply. Start by having a conversation with your GP about prescription weight loss options—they can discuss whether medication is appropriate for you and explain your pathway options.
- 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 detox teas actually effective for weight loss?
Detox teas have minimal scientific evidence for significant weight loss. Some may offer slight appetite support or mild diuretic effects, but results are modest and temporary. For sustainable, clinically proven weight loss, prescription medications like Mounjaro and Wegovy show far stronger evidence—averaging 15–clinically studied weight loss in trials.
What's the difference between Mounjaro and Wegovy for weight loss?
Both are prescription injections approved in the UK for weight management. Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist, while Wegovy (semaglutide) is a GLP-1 agonist only. Mounjaro may offer slightly higher average weight loss in trials (~20.9% vs ~15%), but both require clinical assessment and are used alongside diet and exercise.
How do I know if I'm eligible for NHS weight loss medication?
You typically qualify if your BMI is 30 or above, or 27–29.9 with weight-related health conditions. Use our free BMI calculator to check your BMI. For South Asian or Black heritage adults, lower thresholds apply. Speak to your GP about specialist weight management services in your area—they can assess your individual eligibility.
Can I get prescription weight loss injections privately in the UK?
Yes. Mounjaro, Wegovy, and Saxenda are available through private online prescribing following a clinical assessment with a UK-licensed prescriber. This doesn't require NHS referral, though costs vary. Private access is faster than NHS waiting lists in most areas, but prescription medications are always assessed on individual health needs.
Do prescription weight loss medications work without diet and exercise changes?
No. Mounjaro, Wegovy, and other GLP-1 medications are most effective alongside a reduced-calorie diet and increased physical activity. Clinical trials showed weight loss results when medication was combined with these lifestyle changes. Medication supports weight management but doesn't replace healthy habits—it makes them easier to maintain.
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.