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
Does Cucumber Help in Weight Loss?
Cucumber is often promoted as a weight loss food, and whilst it can support healthy eating, it's not a standalone weight loss solution. At around 96% water and just 16 calories per 100g, cucumber is low in calories and can help you feel fuller. However, sustainable weight management requires a comprehensive approach—combining dietary changes, physical activity, and sometimes prescription medication for eligible adults in the UK. If you're looking to lose weight, understanding your starting point with your BMI is essential. Use our free BMI calculator above to check where you currently stand according to NHS guidelines.
10,000+ calculations today · NHS-aligned thresholds · 100% free
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
For adults struggling with weight management despite lifestyle changes, prescription weight loss medication is available in the UK. Three main options are licensed for weight management:
- Mounjaro (tirzepatide) — a once-weekly injection that works as a dual GIP and GLP-1 receptor agonist, helping regulate appetite and blood sugar
- Wegovy (semaglutide) — a once-weekly GLP-1 injection that supports feeling fuller and reduces food cravings
- Saxenda (liraglutide) — a daily GLP-1 injection option
Clinical trials show these medications can support significant weight loss alongside a reduced-calorie diet and increased physical activity. You're eligible if you have a BMI of 30 or above, or a BMI of 27–29.9 with weight-related health conditions such as type 2 diabetes, hypertension, or sleep apnoea. Try our GLP-1 weight loss calculator to estimate potential weight loss outcomes at different 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.
Getting Prescription Weight Loss Treatment in the UK
There are two routes to access prescription weight loss medication in the UK. The NHS route involves referral from your GP to a specialist tier 3 weight management service, though waiting lists vary significantly by region and availability can be limited. The private route offers faster access through an online clinical assessment with a UK-licensed prescriber, without needing an NHS referral.
To find out if you're eligible, start by speaking with your GP about your weight management goals. They can assess your individual health situation, discuss whether medication might help you, and explain the NHS options available in your area. Even modest weight loss of 5–10% of your body weight can deliver meaningful health benefits.
- 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 lose weight by eating only cucumber?
No. Whilst cucumber is very low in calories and mostly water, eating only cucumber would provide insufficient nutrients, protein, and healthy fats. Sustainable weight loss requires a balanced, reduced-calorie diet that includes vegetables, lean protein, whole grains, and healthy fats. Cucumber can be part of a healthy diet, but it's not a weight loss solution on its own.
What's the difference between Mounjaro and Wegovy for weight loss?
Both are once-weekly injections licensed for weight management in the UK. Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist, whilst Wegovy (semaglutide) is a GLP-1 agonist only. Clinical trials suggest Mounjaro may support slightly higher average weight loss (around 15–21% body weight), but individual results vary. Your prescriber will help determine which is more suitable for you.
How do I know if I'm eligible for prescription weight loss medication?
You may be eligible if you have 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 sleep apnoea. Eligibility also varies by ethnicity—lower thresholds apply for South Asian, Chinese, Black African, and Black Caribbean adults. Your GP or a licensed prescriber can assess your individual eligibility following a clinical evaluation.
What's the difference between NHS and private weight loss medication access?
NHS access involves referral to a specialist weight management service through your GP, though availability and waiting times vary by region. Private access is through an online clinical assessment with a UK-licensed prescriber, offering faster access without an NHS referral. Both require a prescription and clinical assessment; private options typically involve a cost, whilst NHS is free if you're eligible through your local service.
How quickly will I lose weight on prescription medication?
Weight loss varies significantly between individuals. Clinical trials show average weight loss of 15–21% body weight over several months, alongside a reduced-calorie diet and increased physical activity. The pace depends on your starting weight, dose, adherence, diet, and exercise. Your prescriber will monitor your progress regularly and adjust your dose if needed. Avoid comparing your results to others—individual outcomes vary.
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.