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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Easy Weight Loss Meals in the UK
Losing weight successfully often starts with understanding how nutrition fits into your overall weight management plan. In the UK, many adults combine simple, sustainable meal changes with other evidence-based approaches — including prescription weight management options if they're eligible. This guide covers practical meal ideas alongside the prescription medications available to help support weight loss, so you can see the full picture of what's available to you on 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.
Prescription Weight Loss Options Available in the UK
Three prescription-only weight loss medications are licensed in the UK and available for eligible adults. These work alongside healthy eating habits, not instead of them.
- Mounjaro (tirzepatide) — a once-weekly injection that works as a dual GLP-1 and GIP receptor agonist. In clinical trials, participants lost an average of 15–21% of their body weight over 72 weeks, though individual results vary significantly.
- Wegovy (semaglutide) — a once-weekly GLP-1 injection. Average weight loss in clinical trials was around 15% of body weight, alongside a reduced-calorie diet and increased physical activity.
- Saxenda (liraglutide) — a once-daily GLP-1 injection, the longest-established option for weight management in the UK.
To be eligible for any of these medications, you typically need a BMI of 30 or above, or BMI 27–29.9 with at least one weight-related health condition such as type 2 diabetes, high blood pressure, or sleep apnoea. Try our free GLP-1 weight loss calculator to explore potential outcomes at different doses, and use our BMI calculator to check where you currently sit on the NHS weight categories.
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 Access vs Private Prescribing in the UK
NHS access: Prescription weight loss medication is available through specialist tier 3 and tier 4 weight management services. Your GP can refer you, though availability and waiting times vary significantly by region. Some areas have longer waiting lists than others.
Private prescribing: You can access these medications privately through UK-licensed online prescribers following a clinical assessment. This route doesn't require an NHS referral and is often faster, though costs vary by dose and provider.
Regardless of route, all prescription weight loss medications should be combined with sustainable meal planning, increased physical activity, and behaviour change support. Speaking with your GP is always a good starting point — they can assess your individual health, discuss what's available to you locally, and help you decide on the best approach for your situation.
- 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.
What's the difference between easy weight loss meals and prescription medication?
Healthy meals provide sustainable nutrition and create the calorie deficit needed for weight loss. Prescription medications like Mounjaro and Wegovy work by reducing appetite and helping you feel fuller on smaller portions. The two work best together — medication supports you eating less, but the meals you choose still matter for nutrition and long-term success.
Am I eligible for prescription weight loss medication on the NHS?
Eligibility generally requires a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes or high blood pressure. Requirements vary slightly by region and ICB. Your GP can assess your individual eligibility and discuss whether referral to specialist services is appropriate for you.
How quickly can I expect weight loss with prescription medication?
Results vary between individuals, but clinical trials show average losses of 15–21% of body weight over several months. This is achieved alongside reduced-calorie meals and increased physical activity — medication isn't effective without these lifestyle changes. Individual results depend on adherence, your starting weight, and other health factors.
Can I get prescription weight loss injections privately in the UK?
Yes. UK-licensed online prescribers can assess you and issue prescriptions for Mounjaro, Wegovy, or Saxenda if clinically appropriate. These are dispensed by GPhC-registered pharmacies. Private access doesn't require NHS referral and is often faster, though costs vary by medication, dose, and provider.
What should I do if I want to explore weight loss options?
Start by speaking with your GP — they can assess your health, discuss your weight management goals, and explain what's available locally through the NHS. They can also advise on combining simple meal planning with other approaches. Use our free BMI calculator and GLP-1 weight loss calculator to understand your current position and explore potential outcomes before your appointment.
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.