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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Does Berberine Help With Weight Loss in the UK?
Berberine is a plant alkaloid that some research suggests may support modest weight management, but evidence in humans is limited. If you're looking for proven weight loss support in the UK, prescription medications like Mounjaro and Wegovy have strong clinical evidence backing them. This guide explains what berberine is, what the research shows, and what prescription weight management options are available to eligible adults through the NHS or private providers. We'll help you understand which approach 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-Licensed Prescription Weight Loss Options
If you're exploring weight management in the UK, several prescription medications have robust clinical evidence and NHS approval. Mounjaro (tirzepatide) is a once-weekly injection that works as a dual GIP and GLP-1 receptor agonist—in clinical trials, participants lost an average of 15–21% of their body weight. Wegovy (semaglutide) is another once-weekly GLP-1 injection; trial data showed approximately 15% average weight loss alongside dietary changes and physical activity. Saxenda (liraglutide) is a daily injection option.
- All three are prescription-only and require clinical assessment by a UK-licensed prescriber
- Eligibility: BMI of 30 or above, or 27–29.9 with weight-related health conditions
- Individual results vary significantly
- Used alongside reduced-calorie diet and increased physical activity
These medications have undergone rigorous clinical trials and are monitored by the MHRA for safety. Use our free GLP-1 weight loss calculator to explore how these medications might help based on your starting weight and dose.
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, you can access prescription weight loss treatment through two pathways. NHS access is via referral to a tier 3 specialist weight management service from your GP—availability varies by region and waiting times can be lengthy. Private access is through a GPhC-registered online pharmacy following an online clinical assessment with a UK-licensed prescriber; this can be faster but involves costs typically ranging from £129–£320 per month depending on dose.
- Start by speaking with your GP about weight management options available in your area
- Your GP can assess whether prescription medication is appropriate for you
- Check your BMI using our free BMI calculator to understand your eligibility
- Ask about NHS tier 3 services first; if waiting times are long, ask about private 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.
Is berberine proven to help with weight loss?
Berberine shows some promise in animal and small human studies for modest metabolic support, but evidence in humans is limited and weight loss effects are typically very small. It is not licensed as a weight loss medicine in the UK. If you're seeking evidence-backed weight management support, speak to your GP about prescription options like Mounjaro or Wegovy.
What is the difference between berberine and prescription weight loss medication?
Berberine is a supplement with limited clinical evidence for weight loss in humans. Prescription medications like Mounjaro and Wegovy have undergone large rigorous clinical trials, are regulated by the MHRA, and showed average weight loss of 15–21% in participants. Prescription options require clinical assessment; supplements do not.
Am I eligible for NHS weight loss medication?
You may be eligible if you have a BMI of 30 or above, or 27–29.9 with at least one weight-related health condition (type 2 diabetes, high blood pressure, heart disease, sleep apnoea, or abnormal cholesterol). Use our free BMI calculator to check your BMI, then speak with your GP about referral to specialist weight management services.
How much weight can I expect to lose with Mounjaro or Wegovy?
Clinical trials showed average weight loss of 15–21% with Mounjaro and approximately 15% with Wegovy over 68 weeks, alongside diet and physical activity changes. Individual results vary significantly—some people lose more, others less. Your prescriber can discuss realistic expectations based on your individual circumstances.
Can I get prescription weight loss medication privately without an NHS referral?
Yes. Private online prescribing services in the UK can assess you and issue a prescription if appropriate, which is then dispensed by a GPhC-registered pharmacy. This bypasses NHS waiting lists but involves costs. Always use a registered service and ensure the prescriber is UK-licensed for safety and quality assurance.
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.