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
Can Dark Chocolate Help With Weight Loss?
Dark chocolate contains antioxidants and may help reduce cravings, but weight loss ultimately depends on creating a calorie deficit. Whilst chocolate can be part of a balanced diet, many UK adults seeking significant weight loss benefit from evidence-based approaches including lifestyle changes and, where eligible, prescription weight management medication. If you're looking for effective weight loss support, understanding all available options—including both dietary strategies and medical treatments—is important. Use our free BMI calculator to assess your current weight status and explore whether prescription weight loss medication might be suitable for you.
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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 struggling with weight management despite dietary efforts, prescription weight loss medications are available to eligible UK adults. Three GLP-1 based medications are licensed in the UK: Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide).
- Mounjaro: Once-weekly injection, dual GIP/GLP-1 agonist, up to 15mg dose. Clinical trials showed average weight loss of 15–21% of body weight alongside diet and exercise.
- Wegovy: Once-weekly injection, GLP-1 agonist, up to 2.4mg dose. Clinical evidence demonstrates average weight loss around 15% of body weight.
- Saxenda: Daily injection, GLP-1 agonist, up to 3mg dose. Effective for sustained weight management when combined with lifestyle changes.
Eligibility requires a BMI of 30 or above, or 27 or above with weight-related health conditions such as type 2 diabetes, high blood pressure, or cardiovascular disease. Our free GLP-1 weight loss calculator can help you estimate potential outcomes at different doses based on clinical trial data.
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 Medication in the UK
NHS access: Referral to a specialist tier 3 weight management service through your GP. Availability varies significantly by region, and waiting lists can be lengthy in many areas.
Private access: Online consultation with a UK-licensed prescriber, assessment, and dispensing through a GPhC-registered pharmacy—typically faster than NHS routes but at personal cost (approximately £129–£320 per month depending on dose).
Next steps: Talk to your GP about your weight loss goals. They can assess your eligibility, discuss whether prescription medication is appropriate, and explain both NHS and private options. Track your progress using our free weight loss progress tracker as you work towards your health goals. Remember, prescription weight loss medications are most effective when combined with reduced-calorie diet and increased physical activity.
- 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 dark chocolate effective for weight loss?
Dark chocolate may help reduce cravings due to its cocoa content and antioxidants, and can be part of a balanced diet. However, weight loss requires a calorie deficit overall. Dark chocolate is calorie-dense (approximately 150 kcal per 30g), so portion control is essential. It's a supportive food choice, not a weight loss solution by itself.
What's the difference between Mounjaro and Wegovy for weight loss?
Both are prescription-only GLP-1 medications licensed in the UK for weight management. Mounjaro is a dual GIP/GLP-1 agonist with clinical trial data showing 15–21% average weight loss. Wegovy is a GLP-1 agonist with approximately 15% average weight loss in trials. Both require a prescription and clinical assessment. Individual results vary significantly.
Can I get weight loss medication through the NHS?
Yes, GLP-1 medications are available through NHS specialist weight management services (tier 3). You'll need a referral from your GP. Eligibility criteria include BMI of 30 or above, or 27 or above with weight-related health conditions. Availability and waiting times vary considerably by region and local integrated care board decisions.
Am I eligible for prescription weight loss medication?
You may be eligible if you have a BMI of 30 or above, or 27 or above with conditions such as type 2 diabetes, high blood pressure, or sleep apnoea. For South Asian, Chinese, Black African, or Black Caribbean adults, lower thresholds may apply. Use our free BMI calculator to check your current BMI, then discuss eligibility with your GP.
What's the typical cost of weight loss injections privately in the UK?
Private prescription weight loss medications typically cost £129–£320 per month depending on the dose and provider. Mounjaro and Wegovy require escalating doses over 4–5 months, so initial courses are more expensive. Costs vary between pharmacies. Always check with providers for their specific pricing and ensure they're GPhC-registered before purchasing.
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.