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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Vegan Weight Loss Meal Plan and UK Prescription Options
A vegan weight loss meal plan can be an effective dietary approach, but for many people in the UK, prescription weight management medication may offer additional support. If you're following a plant-based diet and considering prescription weight loss options, understanding what's available through the NHS and private prescribing can help you make informed decisions. This guide covers UK-licensed weight loss medications, eligibility criteria, and how to explore whether prescription treatment might suit your needs alongside your vegan lifestyle.
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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 Medications and Eligibility
Three prescription weight loss medications are currently licensed in the UK for eligible adults: Mounjaro (tirzepatide), a dual GIP and GLP-1 receptor agonist; Wegovy (semaglutide), a GLP-1 receptor agonist; and Saxenda (liraglutide), also a GLP-1 receptor agonist. Clinical trials have shown these medications can support weight management when used alongside dietary changes and increased physical activity. Mounjaro helped participants lose an average of 15–21% of their body weight, whilst Wegovy supported average losses of around 15% — though individual results vary significantly.
To be eligible for prescription weight loss medication in the UK, you typically need a BMI of 30 kg/m² or above, or a BMI of 27–29.9 kg/m² if you have weight-related health conditions such as type 2 diabetes, high blood pressure, or cardiovascular disease. These medications are prescription-only and require a clinical assessment by a licensed prescriber to confirm suitability before dispensing. Use our free BMI calculator to check your personal BMI and our GLP-1 weight loss calculator to explore potential outcomes at different doses.
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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 Access vs Private Prescribing in the UK
In the UK, you can access prescription weight loss medication through two routes. The NHS route involves referral to a specialist tier 3 weight management service, typically initiated by your GP. NHS availability varies significantly by region, and waiting lists can be lengthy in many areas. The private route involves an online consultation with a UK-licensed prescriber; if clinically appropriate, a prescription is issued and dispensed by a GPhC-registered pharmacy. Private prescriptions are available without NHS referral and typically cost £129–£320 per month depending on medication and dose.
Start by speaking with your GP about weight loss medication eligibility. Your GP can discuss whether prescription options align with your health goals, refer you to NHS services if available, or advise on private prescribing pathways. Track your progress using our free progress tracker alongside any dietary or medical interventions you choose.
- 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.
Can I take weight loss injections if I follow a vegan diet?
Yes. GLP-1 and GIP/GLP-1 medications work by affecting appetite and satiety signals regardless of diet type. A vegan diet can be compatible with weight loss medication, though you may need to ensure adequate protein intake from plant sources. Always discuss your dietary approach with your prescriber or a registered dietitian.
What's the difference between Mounjaro and Wegovy for weight loss?
Mounjaro (tirzepatide) is a dual GIP and GLP-1 receptor agonist, whilst Wegovy (semaglutide) activates GLP-1 only. Clinical trials showed Mounjaro supported slightly higher average weight loss (15–21% vs ~15%), but both are effective. Individual response varies, and your prescriber will recommend the most suitable option.
How do I know if I'm eligible for NHS weight loss medication?
Generally, you need a BMI of 30 or above, or 27–29.9 with weight-related health conditions. Eligibility criteria can vary by region. Your GP can assess your individual situation and discuss whether you qualify for NHS specialist weight management services in your area.
How quickly can I access prescription weight loss medication privately in the UK?
Private prescribing typically moves faster than NHS referral pathways. You can complete an online consultation within days, and if approved, receive your prescription and first dose within 1–2 weeks. This varies by provider, so check timescales when enquiring.
Do I still need to follow a specific diet if I take weight loss medication?
Yes. Clinical trials show weight loss medications work best alongside a reduced-calorie diet and increased physical activity. A vegan meal plan, combined with calorie awareness and movement, maximises the effectiveness of prescription treatment. Your GP or dietitian can guide personalised dietary support.
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.