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 Dark Chocolate Good For Weight Loss?
Dark chocolate in moderation may offer some modest benefits for weight management—it contains antioxidants and can help reduce cravings for sugary foods. However, it's high in calories, so portion control is essential. If you're looking for evidence-based weight management support beyond dietary changes, prescription weight management medications are now available in the UK for eligible adults. These options work alongside lifestyle changes like improved diet and increased physical activity, not instead of them.
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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 Weight Management Medications
If you're seeking structured support for weight management in the UK, prescription GLP-1 medications are available for eligible adults. These include Mounjaro (tirzepatide), a dual GIP and GLP-1 receptor agonist, and Wegovy (semaglutide), a GLP-1 injection. Both are once-weekly injections licensed specifically for weight loss.
- Mounjaro: Clinical trials showed average weight loss of approximately 15–21% of body weight over 72 weeks when combined with a reduced-calorie diet and physical activity
- Wegovy: Evidence from trials demonstrated average weight loss of around 15% of body weight at the maximum dose
- Saxenda (liraglutide): A daily GLP-1 injection, also available through NHS specialist services and privately
Individual results vary significantly. These are prescription-only medications requiring clinical assessment before dispensing. You can check your BMI using our free BMI calculator to understand whether you may be eligible for consideration.
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: Finding Out If You're Eligible
In the UK, prescription weight loss medication access is available through two main routes. The NHS route is through specialist tier 3 weight management services—you'll need a referral from your GP, and availability varies by region. The private route involves a consultation with a UK-licensed prescriber online, followed by prescription dispensing through a GPhC-registered pharmacy.
Eligibility generally requires a BMI of 30 or above, or 27 or above with weight-related health conditions like type 2 diabetes, high blood pressure, or sleep apnoea. Your GP can advise on NHS pathways, or you can explore private prescribing options. Use our free GLP-1 weight loss calculator to see projected results if you meet eligibility criteria, and speak with your healthcare provider about whether medication-assisted weight loss is right for you.
- 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 actually helpful for weight loss?
Dark chocolate (70% cocoa or higher) contains antioxidants and may reduce cravings for sugary foods, which can help with weight management. However, it's calorie-dense at around 150 calories per 25g portion. Weight loss still requires a calorie deficit overall, so dark chocolate works best in small, measured amounts as part of a balanced diet rather than as a weight loss solution on its own.
What's the difference between Mounjaro and Wegovy for weight loss in the UK?
Both are prescription-only GLP-1-based injections available in the UK. Mounjaro is a dual GIP+GLP-1 agonist with a maximum dose of 15mg weekly, while Wegovy is a GLP-1 agonist with a maximum dose of 2.4mg weekly. Clinical trials showed Mounjaro achieved slightly higher average weight loss (15–21% vs 15%), though individual results vary. Your prescriber will assess which is more suitable for you based on your health profile.
How do I know if I'm eligible for weight loss medication in the UK?
Adults with a BMI of 30 or above are generally eligible. Those with a BMI of 27–29.9 may be eligible if they have weight-related health conditions such as type 2 diabetes, hypertension, or sleep apnoea. Lower thresholds apply for South Asian, Chinese, Black African, and Black Caribbean adults due to higher health risks at lower BMI. Speak to your GP about NHS pathways or consult a UK-licensed prescriber privately to be assessed.
What's the difference between NHS and private weight loss medication access?
NHS access is through specialist tier 3 weight management services (referral from GP required), with availability varying by region and potential waiting lists. Private access is through online consultation with a UK-licensed prescriber, followed by dispensing via GPhC-registered pharmacies—usually available more quickly but at private cost. Both routes require clinical assessment; only prescribed medications should be used.
Can I use weight loss medication instead of changing my diet and exercise?
No. Prescription weight loss medications like Mounjaro and Wegovy are most effective when combined with a reduced-calorie diet and increased physical activity. They support weight management by reducing appetite and cravings, but they're not a replacement for lifestyle changes. Your healthcare provider will discuss how to integrate medication with diet and exercise for the best results.
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.