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
Homemade Fruit Smoothies for Weight Loss
Homemade fruit smoothies can be a healthy addition to a weight loss plan, providing nutrients and fibre that support feeling fuller for longer. However, smoothies alone are not typically enough for sustainable weight management. If you're looking to lose weight in the UK, several approaches exist — from lifestyle changes like smoothies and exercise, to prescription weight loss medication available through NHS specialist services or private prescribing. This guide explores smoothies alongside evidence-based options like GLP-1 medications such as Mounjaro and Wegovy.
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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 looking to lose weight in the UK, prescription medications are available alongside lifestyle changes. Mounjaro (tirzepatide) and Wegovy (semaglutide) are dual and single GLP-1 receptor agonists licensed for weight management.
- Mounjaro: A once-weekly injection. Clinical trials showed average weight loss of 15–21% of body weight over 72 weeks when combined with dietary changes and physical activity.
- Wegovy: Also a once-weekly injection. Trial data showed approximately 15% average body weight loss at maximum dose (2.4 mg).
- Eligibility: Adults with a BMI of 30 or above, or 27 or above with weight-related conditions (type 2 diabetes, high blood pressure, sleep apnoea) may be eligible. South Asian, Chinese, Black African, and Black Caribbean adults may have lower BMI thresholds.
- Individual results vary — weight loss medications work best alongside reduced-calorie diets and increased physical activity.
Try our free GLP-1 weight loss calculator to see projected weight loss at different medication 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
Access to prescription weight loss medication in the UK differs between NHS and private routes. NHS access involves referral from your GP to a tier 3 specialist weight management service — availability varies significantly by region, and waiting lists can be lengthy. Private access is available through GPhC-registered online pharmacies following a clinical assessment with a UK-licensed prescriber, with no NHS referral needed.
Your GP can discuss whether prescription weight management is appropriate for you and provide eligibility assessment. Use our free BMI calculator above to check your personal BMI — this will help inform your conversation with your healthcare provider about which approach suits your health goals and circumstances.
- 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 homemade fruit smoothies alone lead to sustainable weight loss?
Homemade smoothies can support weight loss when part of a reduced-calorie diet, but they're typically not sufficient alone. Sustainable weight management requires consistent calorie deficit, physical activity, and often behavioural changes. For some adults, prescription weight loss medication combined with lifestyle changes may be more effective than diet alone.
Are Mounjaro and Wegovy available on the NHS in the UK?
Yes, both Mounjaro and Wegovy are NICE-approved for NHS use through specialist tier 3 weight management services. However, NHS access varies by region and waiting times can be lengthy. They're also available through private online prescribing services following a clinical assessment by a UK-licensed prescriber.
What is the difference between Mounjaro and Wegovy?
Mounjaro (tirzepatide) is a dual GIP and GLP-1 receptor agonist; Wegovy (semaglutide) is a single GLP-1 agonist. Both are once-weekly injections. Clinical trial data suggests Mounjaro may produce slightly higher average weight loss (15–21% vs 15%), but individual results vary significantly between people.
How do I find out if I'm eligible for prescription weight loss medication in the UK?
Eligibility typically requires a BMI of 30 or above, or 27 or above with a weight-related health condition. Your GP can assess your individual circumstances. Use our free BMI calculator to check your BMI, then speak with your GP about whether prescription weight management is appropriate for your health profile.
How quickly can I expect weight loss with prescription injections?
Weight loss typically begins within the first few weeks, with most significant loss occurring between weeks 12 and 40. However, individual timelines vary. Medications work best alongside a reduced-calorie diet and physical activity. Your prescriber will monitor your progress and adjust doses as needed.
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.