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
Best Berberine for Weight Loss in the UK
Berberine is a natural supplement some people use for weight management, but if you're looking for evidence-based weight management in the UK, prescription medications may be a more effective option. The NHS supports several licensed weight loss injections for eligible adults, including GLP-1 medications like Mounjaro and Wegovy. These prescription options have strong clinical evidence behind them and are available through both NHS specialist services and private prescribing. This guide explains what's available and how to find out if you're eligible.
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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 Management Options
While berberine supplements are available over the counter, the UK's most evidence-backed weight management options are prescription medications. Mounjaro (tirzepatide) is a dual GIP and GLP-1 receptor agonist that helps regulate appetite and support feeling fuller after meals. Wegovy (semaglutide) is a GLP-1 injection licensed for weight management. Both are prescription-only and administered as once-weekly injections. Saxenda (liraglutide) is another GLP-1 option, given as a daily injection. Clinical trials show these medications help achieve an average weight loss of 15–21% of body weight when combined with a reduced-calorie diet and increased physical activity. Eligibility depends on your BMI and health circumstances. Check your BMI using our free BMI calculator to understand where you fall on NHS guidelines, then speak with your GP about whether prescription weight loss medication might be suitable for you.
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 and Private Access to Weight Loss Medication
NHS access: Weight loss injections are available through specialist tier 3 weight management services, typically following a referral from your GP. Availability and waiting times vary significantly across UK regions (integrated care boards). Private access: If you prefer faster access, GPhC-registered online prescribing services can assess your eligibility and issue a prescription without an NHS referral. Costs range from approximately £129–£320 per month depending on the medication and dose. Either route requires a clinical assessment to confirm the medication is safe and appropriate for you. Our GLP-1 weight loss calculator can help you understand potential outcomes at different doses. Your GP remains the best first step—they can advise on NHS options in your area and discuss which approach suits your circumstances.
- 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 berberine prescribed by the NHS for weight loss?
No. Berberine is a natural supplement not licensed or prescribed by the NHS. For weight management in the UK, the NHS recommends prescription medications like Mounjaro and Wegovy for eligible adults. These have clinical trial evidence and are available through specialist weight management services.
What prescription weight loss options are available in the UK?
Three main options: Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide). All are once or twice-weekly injections. Mounjaro and Wegovy are once weekly; Saxenda is daily. All require a clinical assessment and prescription.
Who is eligible for prescription weight loss medication in the UK?
Generally, adults with a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes, high blood pressure, or cardiovascular disease. For some ethnic groups (South Asian, Chinese, Black African/Caribbean), lower thresholds apply due to higher health risks at lower BMI.
How do I find out if I'm eligible for weight loss medication?
Use our free BMI calculator to check your BMI first. Then speak with your GP, who can assess your overall health and refer you to specialist services if appropriate. Private online prescribing services can also conduct a clinical assessment and discuss eligibility.
How much weight loss can I expect with prescription weight loss medication?
Clinical trials show average losses of 15–21% of body weight over several months, depending on the medication and dose. Individual results vary significantly. Weight loss medication works best alongside a reduced-calorie diet and increased physical activity. Track your progress with our free progress tracker.
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.