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
Weight Loss Drinking Smoothies and Prescription Medication in the UK
Smoothies can be part of a healthy weight management approach, but for many people seeking to lose weight in the UK, prescription medication alongside dietary changes may offer additional support. This guide explores how smoothies fit into weight loss strategies and introduces the UK-licensed prescription options available for eligible adults, including Mounjaro, Wegovy, and Saxenda. Whether you're managing your weight through nutrition alone or considering medication, understanding all available options helps you make informed decisions with your GP.
10,000+ calculations today · NHS-aligned thresholds · 100% free
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 Management Options
For adults who meet NHS weight loss eligibility criteria, three prescription-only medications are currently licensed in the UK for weight management. Mounjaro (tirzepatide) is a once-weekly dual GIP and GLP-1 receptor agonist injection; clinical trials showed participants lost an average of 15–21% of their body weight. Wegovy (semaglutide) is also a once-weekly GLP-1 injection, with trial data showing approximately 15% average body weight loss. Saxenda (liraglutide) is a daily GLP-1 injection offering similar weight loss support.
These medications work by regulating appetite signals and may help you feel fuller after smaller meals. Individual results vary significantly. All are prescription-only and require a clinical assessment before being prescribed. They are typically used alongside dietary changes—including nutritious smoothies—and increased physical activity, not as replacements for lifestyle modifications.
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 Eligibility
NHS access: Weight loss medication is available through NHS specialist tier 3 weight management services, though access varies by region and waiting times can be substantial. Referral typically comes from your GP. Private access: Prescription weight loss medication is available through online consultations with UK-licensed prescribers and dispensed by GPhC-registered pharmacies, without NHS referral.
To find out if you're eligible for weight loss support, calculate your BMI using our free BMI calculator on this page. Adults with a BMI of 30 or above, or 27 and above with weight-related health conditions, may be eligible for prescription treatment. The best starting point is a conversation with your GP, who can assess your individual circumstances and discuss whether prescription weight management alongside smoothies and lifestyle changes 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.
Can smoothies help with weight loss?
Yes, smoothies can support weight loss when made thoughtfully. High-protein, fibre-rich smoothies with vegetables, fruit, and protein powder can help you feel fuller for longer, supporting a calorie deficit. However, shop-bought sweetened smoothies may be high in sugar and calories. Home-made smoothies give you control over ingredients and calorie content.
What are the eligibility criteria for prescription weight loss medication in the UK?
Adults with a BMI of 30 kg/m² or above are eligible; those with a BMI of 27–29.9 and at least one weight-related health condition (type 2 diabetes, high blood pressure, sleep apnoea) may also qualify. South Asian, Chinese, Black African, and Black Caribbean adults have lower thresholds due to higher health risks at lower BMI levels. Your GP can assess your individual eligibility.
How much weight can you lose with Mounjaro or Wegovy?
Clinical trials show average weight loss of 15–21% of body weight with Mounjaro and approximately 15% with Wegovy, alongside dietary changes and physical activity. However, individual results vary significantly—some people lose more, others less. These are averages, not assures. Results depend on adherence, lifestyle changes, and personal factors.
Can I use smoothies while taking weight loss medication?
Yes. Smoothies can be part of a healthy diet while taking prescription weight loss medication. However, be mindful of calorie and sugar content. High-protein smoothies with vegetables and whole fruits support weight loss better than sugary versions. Your prescriber or a registered dietitian can advise on nutrition alongside medication.
How do I start the conversation about weight loss medication with my GP?
Book an appointment and discuss your weight management goals. Mention your BMI using our free weight loss calculator, any weight-related health conditions, and previous weight loss attempts. Your GP can assess whether prescription medication is appropriate for you and discuss available options through NHS services or private routes.
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.