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
Smoothie for Weight Loss — And Other UK Weight Management Options
Smoothies can be a useful part of a weight loss plan when made with the right ingredients — but they work best alongside other lifestyle changes. If you're looking to lose weight in the UK, you have several options available, from dietary approaches to prescription weight management medication. This guide explains how smoothies fit into a broader weight loss strategy, and explores prescription options like GLP-1 injections that may help eligible adults achieve sustainable results.
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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 in the UK who are struggling to lose weight through diet and exercise alone, prescription weight management medications are available on the NHS and privately. These include Mounjaro (tirzepatide), a dual GIP and GLP-1 receptor agonist, and Wegovy (semaglutide), a GLP-1 injection. Clinical trials showed that Mounjaro helped participants lose an average of 15–21% of their body weight, whilst Wegovy supported losses of around 15% on average — though individual results vary significantly.
- Mounjaro: Once-weekly injection, doses from 2.5 mg to 15 mg, prescription-only, requires clinical assessment
- Wegovy: Once-weekly injection, doses from 0.25 mg to 2.4 mg, prescription-only, requires clinical assessment
- Saxenda (liraglutide): Once-daily injection, also available for weight management in eligible adults
All prescription weight loss medications work most effectively alongside a reduced-calorie diet and increased physical activity — similar to how smoothies are most effective as part of a balanced approach rather than a standalone solution.
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.
Who is Eligible and How to Access Weight Loss Support
In the UK, adults with a BMI of 30 or above, or a BMI of 27–29.9 with weight-related health conditions (such as type 2 diabetes, high blood pressure, or sleep apnoea), may be eligible for prescription weight loss treatment. Access is available through two routes: the NHS specialist weight management services (via GP referral to tier 3 services), or private online prescribing through GPhC-registered pharmacies.
- Check your BMI using our free BMI calculator to assess your starting point
- Speak with your GP about eligibility and NHS options in your area
- Consider private prescribing if NHS waiting lists are long (commonly several months to over a year)
- Track your progress with our free progress tracker once you begin any weight loss plan
Whether you choose smoothies, medication, or a combination approach, sustainable weight loss requires commitment and professional guidance.
- 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 a smoothie alone help me lose weight?
Smoothies can support weight loss when low in added sugar and calories, but they work best as part of a broader diet plan. A typical weight loss approach requires a calorie deficit of around 500 kcal per day to lose approximately 0.5 kg per week. Using our free weight converter and BMI calculator can help you set realistic weight loss targets based on your current weight and height in UK measurements.
How do GLP-1 injections like Wegovy and Mounjaro work for weight loss?
GLP-1 medications work by activating hormones that reduce appetite, help you feel fuller after smaller meals, and slow how quickly food leaves your stomach. Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist, whilst Wegovy (semaglutide) is a GLP-1 agonist only. Both are prescription-only and require a clinical assessment before being prescribed. Try our GLP-1 weight loss calculator to explore potential outcomes at different doses.
What's the difference between NHS and private weight loss medication access in the UK?
NHS access is through specialist tier 3 weight management services (referral from your GP) but waiting lists vary significantly by region — often several months to over a year. Private access is available through online prescribing services following a clinical assessment, usually available within days to weeks. Private costs range from approximately £129–£320 per month depending on the medication and dose.
Am I eligible for prescription weight loss medication on the NHS?
Generally, you may be eligible if you have a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes, hypertension, or sleep apnoea. For South Asian, Chinese, Black African, or Black Caribbean adults, lower BMI thresholds may apply. Check your BMI using our free calculator and discuss eligibility with your GP, who can refer you to specialist weight management services.
Is weight loss medication safe to use alongside dietary changes like smoothies?
Yes — prescription weight loss medications are most effective when combined with a reduced-calorie diet and increased physical activity. Smoothies made with whole fruit, vegetables, and protein can support this approach. However, inform your prescriber about all dietary changes and use our progress tracker to monitor your weight loss journey safely and sustainably.
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.