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 Meal for Weight Loss — UK Nutrition and Medication Guide
There's no single "best meal" for weight loss, but evidence-backed principles can guide your choices. Successful weight management in the UK typically combines nutrient-dense meals with a calorie deficit—and for some adults, prescription medication may support those efforts. This guide covers meal planning strategies and explores UK-licensed weight loss options available through NHS or private prescribing, including GLP-1 medications like Mounjaro and Wegovy. Whether you're starting a weight management journey or considering medication, understanding your options helps you make informed decisions with your GP.
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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 Weight Loss Medications and Eligibility
For adults in the UK struggling with weight management, prescription weight loss medications are now available through NHS specialist services and private prescribers. The most widely prescribed options are Mounjaro (tirzepatide) and Wegovy (semaglutide), both licensed GLP-1 and GIP/GLP-1 receptor agonist injections.
Who may be eligible:
- Adults with a BMI of 30 kg/m² or above
- Adults with a BMI of 27–29.9 with weight-related health conditions (type 2 diabetes, hypertension, sleep apnoea)
- Lower BMI thresholds may apply for South Asian, Chinese, Black African, or Black Caribbean adults
In clinical trials, Mounjaro helped adults lose an average of 15–21% of their body weight over 72 weeks, while Wegovy showed approximately 15% average weight loss. Crucially, these results were achieved alongside reduced-calorie meals and increased physical activity—medication is not a substitute for lifestyle changes. Try our free GLP-1 weight loss calculator to estimate potential results at different medication doses.
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 and Next Steps
In the UK, you can access prescription weight loss medication through two routes: NHS specialist tier 3/4 weight management services (via GP referral, though waiting lists vary significantly by region) or private online prescribers following a clinical assessment.
Before considering medication, calculate your personal BMI using our free BMI calculator to understand where you sit on NHS guidelines. If you're interested in exploring prescription options, book an appointment with your GP to discuss your weight management goals and whether medication might be appropriate for you. Your GP can also refer you to NHS services or discuss private options. Remember that sustainable weight loss combines the right meals, physical activity, and—if eligible—medical support tailored to your individual health needs.
- 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 makes the best meal for weight loss?
The best weight loss meals focus on high protein, plenty of vegetables, and whole grains—creating a calorie deficit while maintaining satiety. Protein helps preserve muscle during weight loss. The NHS recommends reducing portion sizes and limiting high-calorie foods like sugary drinks and ultra-processed items. Consistency matters more than perfection.
Can I lose weight with diet alone or do I need medication?
Many people successfully lose weight through diet and exercise alone. However, if you have tried lifestyle changes without sufficient results and meet eligibility criteria (BMI 30+ or BMI 27+ with health conditions), prescription weight loss medication may help. It works best combined with healthy meals and activity—not instead of them.
How do I know if I'm eligible for NHS weight loss medication?
Eligibility typically requires a BMI of 30 or above, or 27–29.9 with weight-related conditions like type 2 diabetes or hypertension. Book a GP appointment to discuss your weight and health. Your GP can assess you for NHS tier 3 specialist services or discuss private prescribing options available in the UK.
What's the difference between Mounjaro and Wegovy for weight loss?
Both are once-weekly injections licensed in the UK for weight management. Mounjaro (tirzepatide) is a dual GIP/GLP-1 agonist with an average weight loss of 15–21% in trials. Wegovy (semaglutide) is a GLP-1 agonist with approximately 15% average weight loss. Both require prescription and work best with healthy meals and exercise.
How much weight can I expect to lose with medication?
Clinical trials show average weight loss of 15–21% with Mounjaro and approximately 15% with Wegovy over several months—but individual results vary significantly. Our GLP-1 weight loss calculator can help estimate potential outcomes. Medication works alongside, not instead of, dietary changes and physical activity.
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.