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 Weight Loss?
Cucumber is low in calories and high in water, which may support weight management when part of a balanced diet. However, no single food causes weight loss on its own. For adults looking for more structured weight management in the UK, prescription options are available through NHS specialist services or private prescribing. If you have a BMI of 30 or above, or 27 or above with weight-related health conditions, you may be eligible for prescription weight loss medication. Your GP can assess your individual situation and discuss what's available.
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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 Prescription Weight Loss Options
For adults in the UK with a BMI of 30 or above (or 27 or above with weight-related conditions such as type 2 diabetes, high blood pressure, or heart disease), prescription weight loss medication is available alongside lifestyle changes like diet and exercise. The main UK-licensed options are:
- Mounjaro (tirzepatide) — dual GIP and GLP-1 receptor agonist, once-weekly injection. Clinical trials showed average weight loss of 15–21% of body weight.
- Wegovy (semaglutide) — GLP-1 receptor agonist, once-weekly injection. Clinical trials showed average weight loss around 15% of body weight.
- Saxenda (liraglutide) — GLP-1 receptor agonist, daily injection.
Individual results with GLP-1 weight loss medication vary significantly. These prescription medicines work alongside reduced-calorie diet and increased physical activity, not instead of them. All require a prescription following clinical assessment from a licensed prescriber.
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.
How to Access Weight Loss Support in the UK
If you're interested in weight management in the UK, your first step is to speak with your GP. They can assess your BMI, health history, and eligibility for prescription options. NHS access is through specialist tier 3 weight management services via referral, though waiting times vary by region. Private access is available through licensed online prescribers without NHS referral. Use our free BMI calculator above to check your starting point, and try our GLP-1 weight loss calculator to estimate potential results with medication at different doses. Whether you choose lifestyle changes alone or add prescription support, sustainable weight management combines diet, physical activity, and behaviour change.
- 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 cucumber alone enough for weight loss?
Cucumber is low in calories and mostly water, making it filling for few calories. However, no single food causes weight loss. Sustainable weight loss requires overall calorie deficit, usually around 500 kcal per day for 0.5 kg weekly loss. Cucumber can support this as part of a balanced, reduced-calorie diet, but is not a standalone solution.
What's the difference between Mounjaro and Wegovy for weight loss?
Both are once-weekly injections available in the UK for weight management. Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist; Wegovy (semaglutide) is a GLP-1 agonist only. In clinical trials, Mounjaro showed average weight loss of 15–21%, Wegovy around 15%. Individual results vary. Your prescriber will determine which is more suitable for you.
Can I get Mounjaro or Wegovy through the NHS?
Yes, both are available through NHS specialist tier 3 weight management services. You'll need a GP referral. Availability and waiting times vary significantly by region. Private access is also available through licensed UK prescribers without NHS referral. Speak with your GP about options in your area.
What's the NHS recommendation for safe weight loss?
The NHS recommends losing no more than 0.5–1 kg (1–2 lbs) per week for sustainable results. This typically requires a calorie deficit of around 500 kcal per day. Faster weight loss is possible with medical support but increases the risk of muscle loss. Always speak with a healthcare professional before starting any weight loss programme.
Do I need to change my diet if I take Mounjaro or Wegovy?
Yes. Prescription weight loss medications work alongside lifestyle changes, not instead of them. The UK clinical pathway for these medicines includes reduced-calorie diet and increased physical activity as essential parts of the plan. Your prescriber will discuss nutrition and exercise support with you, often including access to dietitian advice.
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.