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
Is Popcorn Good for Weight Loss?
Popcorn can be part of a weight loss diet when prepared healthily and eaten in controlled portions. Air-popped popcorn is high in fibre and low in calories — around 30 calories per cup — making it a satisfying snack for many people managing their weight in the UK. However, weight loss ultimately depends on overall calorie intake and lifestyle. For those struggling with appetite control or needing additional support, prescription weight management options are now available through the NHS and private providers. Use our free BMI calculator above to check your current weight status and understand your personal health context.
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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
If popcorn and dietary changes alone aren't delivering results, three UK-licensed prescription medications are available for eligible adults. Mounjaro (tirzepatide) and Wegovy (semaglutide) are once-weekly injections; Saxenda (liraglutide) is a daily injection. These are GLP-1 receptor agonists (or dual GIP/GLP-1 in Mounjaro's case) that help reduce appetite and support feeling fuller after smaller meals.
- Mounjaro: clinical trials showed average weight loss of 15–21% body weight over 72 weeks
- Wegovy: clinical trials showed average weight loss of approximately 15% body weight over 68 weeks
- All three are prescription-only and require clinical assessment before being prescribed
These medications work best alongside dietary changes — including healthier snacking choices like popcorn — and increased physical activity. Individual results vary significantly.
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
NHS route: You can ask your GP for a referral to your local tier 3 specialist weight management service. Eligibility depends on your BMI and whether you have weight-related health conditions. Waiting times vary by region — some areas have significant delays.
Private route: GPhC-registered online prescribers offer consultations and prescription weight loss medication without NHS referral. A licensed clinician will assess your suitability based on your health history and current BMI. To find out if you're eligible for any prescription weight loss support, use our free GLP-1 weight loss calculator or discuss your BMI and health with your GP first.
- 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 air-popped popcorn really low in calories for weight loss?
Yes. Air-popped popcorn contains approximately 30 calories per cup (about 8g) with no added oil or butter. This makes it a relatively low-calorie snack compared to many alternatives. However, weight loss depends on total daily calorie intake, not individual foods. Butter-popped or heavily seasoned popcorn can contain 50+ calories per cup, so preparation method matters.
Can I lose weight with diet and exercise alone, or do I need medication?
Many people lose weight through diet and exercise alone — this is the first step recommended by the NHS. However, if you've tried these approaches and aren't seeing results, or if you have a BMI of 30 or above (or 27+ with weight-related health conditions), prescription weight loss medication may be worth discussing with your GP. A healthcare professional can assess whether medication is appropriate for you.
What is the difference between Mounjaro and Wegovy for weight loss?
Both are prescription-only injections taken once weekly, but Mounjaro (tirzepatide) is a dual GIP/GLP-1 receptor agonist, while Wegovy (semaglutide) is a GLP-1 agonist only. Clinical trials showed Mounjaro achieved slightly higher average weight loss (15–21%) compared to Wegovy (around 15%), though results vary between individuals. Your prescriber will assess which is most suitable for you.
How do I know if I'm eligible for prescription weight loss medication in the UK?
You're generally eligible if your BMI is 30 or above, or 27–29.9 with at least one weight-related health condition (such as type 2 diabetes, high blood pressure, or sleep apnoea). South Asian, Chinese, Black African, and Black Caribbean adults may have lower BMI thresholds. Your GP or a licensed prescriber can assess your individual eligibility following a clinical consultation.
Are prescription weight loss injections available on the NHS?
Yes, tirzepatide (Mounjaro) and semaglutide (Wegovy) are approved for use on the NHS, but access is through specialist tier 3 weight management services — not standard GP prescription. Referral, assessment, and waiting times vary significantly by region. Private online prescribing is also available and does not require NHS referral, though there is a cost.
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.