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
Kombucha for Weight Loss — What Works in the UK
Kombucha is a fermented tea drink often promoted for weight loss, but evidence for significant weight loss is limited. While it may have minor digestive benefits, the real options for meaningful weight management in the UK are prescription medications and lifestyle changes. If you're looking to lose weight, understanding what actually works — alongside your BMI — is essential. This guide explains the science and introduces UK-approved alternatives.
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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-Approved Prescription Weight Loss Options
If you have a BMI of 30 or above, or 27 or above with weight-related health conditions, you may be eligible for prescription weight loss medication in the UK. Three medications are licensed for weight management:
- Mounjaro (tirzepatide) — dual GIP and GLP-1 receptor agonist. Clinical trials showed average weight loss of 15–21% body weight alongside a reduced-calorie diet and increased physical activity.
- Wegovy (semaglutide) — GLP-1 receptor agonist. Average weight loss approximately 15% body weight in trials.
- Saxenda (liraglutide) — GLP-1 receptor agonist taken daily. Long-established option with moderate weight loss support.
All are prescription-only and require clinical assessment. Use our free BMI calculator above to check if you might be eligible, and try our GLP-1 weight loss calculator to see projected 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 — How to Get Started
In the UK, prescription weight loss medication is accessed through two routes. NHS access requires referral to a specialist tier 3 weight management service by your GP — availability varies significantly by region and waiting times can be lengthy. Private access is available through GPhC-registered online prescribing services following a clinical assessment; this route is faster but involves cost.
Your first step is a conversation with your GP about your weight and health. They can assess whether you're eligible, discuss your options, and refer you to specialist services if appropriate. Track your progress with our free progress tracker once you start any weight management plan.
- 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 kombucha actually help with weight loss?
Kombucha contains probiotics and antioxidants, which may support general gut health, but there is no strong scientific evidence that kombucha causes significant weight loss. Any weight loss associated with kombucha is likely due to replacing sugary drinks with a lower-calorie option, not kombucha itself.
What is the most effective weight loss medication in the UK?
Mounjaro and Wegovy are both effective prescription options. Clinical trials show Mounjaro may have a slight edge in average weight loss (15–21% vs 15%), but individual results vary significantly. Your prescriber will recommend the most suitable option based on your health profile.
Am I eligible for prescription weight loss treatment on the NHS?
You may be eligible if your BMI is 30 or above, or 27 or above with weight-related health conditions like diabetes, high blood pressure, or sleep apnoea. Use our free BMI calculator above to check your BMI, then discuss eligibility with your GP.
How quickly can I access prescription weight loss medication?
Private prescribing can be arranged within days to weeks. NHS access typically involves a referral to specialist services, which can take months depending on your region. Contact your GP for NHS referral or explore private GPhC-registered services for faster access.
Can I use prescription weight loss medication without lifestyle changes?
No. All UK-licensed weight loss medications are designed to be used alongside a reduced-calorie diet and increased physical activity. Medication works best when combined with behavioural changes — this approach gives the best long-term results.
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.