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
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Best Weight Loss Smoothies and Prescription Options in the UK
Weight loss smoothies can be a helpful addition to a healthy diet, but for many people in the UK, they work best alongside a structured weight management plan. If you're looking to lose weight, you have several options available — from dietary changes and lifestyle adjustments to prescription weight loss medication. This guide covers both nutritious smoothie ideas and the prescription weight management options available through the NHS and private prescribers in the UK, so you can understand the full range of support available to 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.
Prescription Weight Loss Options Available in the UK
If smoothies and lifestyle changes alone aren't delivering the results you need, prescription weight loss medications are available in the UK for eligible adults. The most commonly prescribed options are GLP-1 weight loss injections, which can support weight management uk programmes when combined with dietary changes.
Three prescription medications are licensed for weight management in the UK:
- Mounjaro (tirzepatide) — a once-weekly injection that activates dual GIP and GLP-1 pathways. Clinical trials showed average weight loss of 15–21% of body weight over 72 weeks.
- Wegovy (semaglutide) — a once-weekly GLP-1 injection. Clinical trials demonstrated average weight loss of approximately 15% of body weight.
- Saxenda (liraglutide) — a daily GLP-1 injection option, though less commonly prescribed than the once-weekly alternatives.
These are prescription-only medicines that require clinical assessment. Our GLP-1 weight loss calculator can help you explore potential outcomes at different doses, though individual results vary significantly. Weight loss injections work best alongside a reduced-calorie diet and increased physical activity — they're not a replacement for lifestyle changes.
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 Find Out if You're Eligible
NHS access: Prescription weight loss medication is available through specialist tier 3 and tier 4 weight management services, but not routinely through your GP. Eligibility typically requires a BMI of 30 or above, or 27–29.9 with weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea. Access varies significantly by region, and waiting lists can be lengthy. Your GP can refer you to your local weight management service if you meet criteria.
Private access: You can also access prescription weight loss treatment through GPhC-registered online prescribers without an NHS referral. A licensed prescriber will assess your eligibility following an online consultation.
To understand your starting point, use our free BMI calculator to check your personal BMI, and discuss your options with your GP — they can advise on NHS availability in your area and whether prescription weight loss medication might be appropriate 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.
Can weight loss smoothies alone help me lose weight?
Yes, nutrient-dense smoothies can support weight loss by providing filling meals within a calorie deficit. However, results depend on overall calorie intake and lifestyle. If you have a BMI over 30 or significant weight-related health conditions, speak to your GP about additional support options, including prescription weight loss medication for eligible adults.
What's the difference between Mounjaro and Wegovy for weight loss?
Both are once-weekly injections licensed for weight management in the UK. Mounjaro (tirzepatide) activates two hormone pathways (GIP and GLP-1) and showed average weight loss of 15–21% in trials. Wegovy (semaglutide) activates the GLP-1 pathway alone with average weight loss of approximately 15%. Both require prescription and clinical assessment.
How do I know if I'm eligible for prescription weight loss treatment on the NHS?
You typically need a BMI of 30 or above, or 25–29.9 with weight-related health conditions. Eligibility thresholds may be lower for adults of South Asian, Chinese, Black African, or Caribbean heritage. Speak to your GP about referral to your local specialist weight management service to check your individual eligibility.
Are weight loss injections available privately in the UK without NHS waiting lists?
Yes. Private prescribing services can assess and prescribe GLP-1 medications following an online consultation. You don't need an NHS referral. However, prescription medications require a proper clinical assessment regardless of whether you access them through the NHS or privately.
Can I use smoothies and weight loss injections together?
Yes. Prescription weight loss medications work best alongside a balanced, reduced-calorie diet and increased physical activity. Healthy smoothies can form part of your overall nutrition plan. Always discuss your complete diet and any new supplements with your prescriber.
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.