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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Best Tea Cleanse For Weight Loss — What Actually Works in the UK
Tea cleanses are popular, but evidence doesn't support them for sustainable weight loss. If you're looking for effective weight management in the UK, prescription medications like Mounjaro and Wegovy have clinical evidence behind them. This guide explains what works, who's eligible, and how to access prescription weight loss support through the NHS or privately.
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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
While herbal teas may have minor health benefits, they don't address the underlying mechanisms of weight loss. Prescription weight loss medications are evidence-based alternatives available in the UK:
- Mounjaro (tirzepatide) — a dual GIP and GLP-1 receptor agonist. 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 receptor agonist. STEP trial data showed an average weight loss of approximately 14.9% of body weight at 68 weeks.
- Saxenda (liraglutide) — a daily GLP-1 injection, also licensed for weight management in UK adults.
All three are prescription-only medicines that require a clinical assessment. Weight loss results vary significantly between individuals, and medication is most effective when combined with dietary changes and physical activity.
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
You can access prescription weight management through two routes in the UK:
- NHS route: Ask your GP for a referral to a tier 3 specialist weight management service. Eligibility depends on your BMI and health conditions. Availability varies by region — some areas have waiting lists of several months.
- Private route: Online consultations with UK-licensed prescribers are available without NHS referral. A clinical assessment determines suitability, and medication is dispensed by GPhC-registered pharmacies.
Your GP can advise you on eligibility and which route is best for your situation. Use our free BMI calculator to check your current BMI and understand your health context.
- 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.
Do tea cleanses actually work for weight loss?
There is no clinical evidence that tea cleanses produce sustainable weight loss. While some herbal teas may have minor diuretic or metabolic effects, any weight loss is typically temporary water loss, not fat loss. Sustainable weight loss requires a calorie deficit and lifestyle changes.
What are the NHS eligibility criteria for prescription weight loss medication?
Adults with a BMI of 30 or above, or 27 or above with at least one weight-related health condition (such as type 2 diabetes, high blood pressure, or sleep apnoea), may be eligible. Eligibility is assessed individually by your GP or specialist. Use our free BMI calculator to check your personal BMI.
How much weight can I expect to lose with Mounjaro or Wegovy?
Clinical trials showed average weight loss of around 15–21% of body weight with Mounjaro and 14.9% with Wegovy over 68–72 weeks. However, individual results vary significantly. Weight loss is achieved alongside a reduced-calorie diet and increased physical activity — medication alone is not enough.
Can I get Mounjaro or Wegovy on the NHS?
Yes, both are available through NHS specialist weight management services. Access is typically through a tier 3 service after GP referral. Availability and waiting times vary by region. Your GP can advise whether you meet local eligibility criteria and how to access specialist services.
How do I find out if I'm eligible for prescription weight loss treatment in the UK?
Start by speaking with your GP. They can assess your BMI, health conditions, and medical history to determine eligibility for specialist referral. Alternatively, private online consultations with UK-licensed prescribers can provide a clinical assessment without NHS referral. Our GLP-1 weight loss calculator can help you understand potential outcomes if you're considering medication.
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.