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
Prepared Meal Delivery and Weight Loss Medication in the UK
Prepared meal delivery services can help with portion control and calorie management as part of a weight loss plan, but they work best alongside other strategies. If you're looking to lose weight in the UK, you may also be eligible for prescription weight management options. Our guide explains UK-licensed medications, eligibility criteria, and how to access support through the NHS or privately. Use our free BMI calculator to check where you stand first.
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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
Three prescription-only weight management medications are licensed in the UK for eligible adults. Mounjaro (tirzepatide) is a once-weekly injection that works as a dual GIP and GLP-1 receptor agonist, helping regulate appetite and support weight loss through clinical trials showing average weight loss of 15–21% body weight. Wegovy (semaglutide) is also a once-weekly injection using the GLP-1 mechanism, with clinical trials showing average weight loss of around 15% body weight. Saxenda (liraglutide) is a daily injection and the longest-established option in the UK.
To be eligible for these medications, you typically need a BMI of 30 or above, or a BMI of 27–29.9 with a weight-related health condition such as type 2 diabetes, high blood pressure, or cardiovascular disease. All three are prescribed following a clinical assessment—they are not available over the counter. When combined with reduced-calorie diet and physical activity (including structured meal planning), these medications may significantly support your weight management journey. Individual results vary considerably.
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.
Accessing Weight Management Support: NHS vs Private
NHS access: Prescription weight loss medications are available through tier 3 specialist weight management services. You'll need a referral from your GP, though availability varies significantly by region and waiting times can be lengthy. Your GP can discuss whether you meet eligibility criteria and whether referral is appropriate for your situation.
Private access: You can access prescription weight loss treatment privately through GPhC-registered online prescribing services, which typically involve an online consultation with a UK-licensed prescriber. This route doesn't require an NHS referral. Try our free GLP-1 weight loss calculator to estimate potential outcomes at different doses. Whether you choose NHS or private support, combine medication with balanced nutrition—prepared meals can help with this—alongside physical activity for best results.
- 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 prepared meal delivery alone help me lose weight?
Prepared meals can support weight loss by controlling portions and calories, but sustainable results typically require a calorie deficit combined with physical activity. For some people, prescription medication alongside meals and exercise may be more effective. Your GP can advise what's right for you.
Who is eligible for prescription weight loss medication in the UK?
Adults with a BMI of 30 or above, or 27–29.9 with weight-related health conditions (diabetes, high blood pressure, cardiovascular disease), may be eligible. Eligibility is assessed individually following a clinical consultation with a prescriber.
What's the difference between Mounjaro and Wegovy?
Both are once-weekly injections for weight management. Mounjaro uses dual GIP and GLP-1 mechanisms and may produce slightly higher average weight loss (15–21%). Wegovy uses GLP-1 alone with average weight loss around 15%. Individual results vary; your prescriber will recommend the best option for you.
How do I access weight loss medication on the NHS?
Ask your GP for a referral to your local tier 3 specialist weight management service. They'll assess eligibility and prescribe if appropriate. Waiting times vary by region. Private prescribing is available without an NHS referral through registered online services.
Should I use prepared meals with weight loss medication?
Yes—prepared meals can make it easier to stick to the reduced-calorie diet often recommended alongside medication. They support portion control and help you manage appetite while the medication works. Combine both with regular physical activity for best 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.