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 Aid Weight Loss?
Cucumber is low in calories and high in water, making it a nutritious addition to a healthy diet — but eating cucumber alone won't lead to weight loss. Weight management in the UK requires a sustained calorie deficit, usually combined with physical activity. For adults struggling with weight management despite lifestyle changes, prescription weight loss medications like Mounjaro and Wegovy are now available through the NHS and private prescribing. These evidence-based options can support weight loss when combined with dietary improvements and exercise.
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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
If you're interested in weight management in the UK, prescription medications are available for eligible adults. Mounjaro (tirzepatide) and Wegovy (semaglutide) are once-weekly injections that work by regulating appetite and helping you feel fuller after smaller meals. Clinical trials showed Mounjaro helps users lose an average of 15–21% of body weight, while Wegovy supports approximately clinically studied weight loss — individual results vary significantly.
- Mounjaro: GIP and GLP-1 receptor agonist, doses 2.5–15 mg weekly
- Wegovy: GLP-1 receptor agonist, doses 0.25–2.4 mg weekly
- Saxenda: GLP-1 receptor agonist, daily injection option
All require a prescription and are only suitable for adults with a BMI of 30 or above, or 27–29.9 with weight-related health conditions. Use our free GLP-1 weight loss calculator to explore projected 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.
NHS vs Private Access and How to Get Started
In the UK, glp-1 weight loss medications are available through two routes. NHS access is through specialist tier 3 weight management services — your GP can refer you, though waiting lists vary by region. Private prescribing is faster, available through online consultations with UK-licensed prescribers followed by dispensing through GPhC-registered pharmacies.
To find out if you're eligible, check your BMI using our free BMI calculator, then speak with your GP or a licensed prescriber about prescription weight loss options. They'll assess your individual health, discuss side effects, and determine whether medication is appropriate for you. Lifestyle changes — diet and exercise — remain essential alongside any medication.
- 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 actually effective for weight loss?
Cucumber is low in calories (about 16 calories per 100g) and high in water, so it's a nutritious, low-calorie food choice. However, eating cucumber alone won't lead to weight loss — you need a sustained calorie deficit. Cucumber works best as part of a balanced, reduced-calorie diet combined with physical activity.
What prescription weight loss options are available in the UK?
Mounjaro, Wegovy, and Saxenda are the three GLP-1/GIP medications licensed for weight management in the UK. All require a prescription and clinical assessment. Mounjaro and Wegovy are once-weekly injections; Saxenda is a daily injection. Eligibility typically requires a BMI of 30 or above, or 27–29.9 with weight-related health conditions.
How do I access weight loss medication on the NHS in the UK?
Ask your GP for a referral to your local NHS specialist weight management service (tier 3). They'll assess your eligibility and may prescribe medication if appropriate. Waiting times vary by region. Private online prescribing is an alternative if you meet eligibility criteria and prefer a faster route.
How much weight can you lose with Mounjaro or Wegovy?
Clinical trials showed average weight loss of 15–21% of body weight with Mounjaro and approximately 15% with Wegovy over 12–18 months. Individual results vary significantly based on genetics, lifestyle changes, and adherence. Weight loss is most effective alongside reduced-calorie diet and increased physical activity.
Are prescription weight loss injections safe?
Mounjaro and Wegovy are approved by the MHRA and have been used safely in clinical trials. Like all medications, they have potential side effects — most commonly nausea, diarrhoea, and constipation, which often reduce over time. Your prescriber will assess whether the medication is safe and appropriate for your individual health profile.
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.