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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Weight Loss Protein Shake For Breakfast — And Prescription Options
A protein-rich breakfast, including protein shakes, can support weight loss by increasing satiety and reducing overall calorie intake throughout the day. However, for adults struggling with weight management, prescription weight loss medications are now available in the UK through the NHS and private prescribing. This guide explains how breakfast nutrition fits into sustainable weight loss, and what prescription options eligible adults should know about for effective weight management in the UK.
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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 Prescription Weight Loss Options
For eligible UK adults, prescription weight loss medications offer evidence-based support alongside dietary changes like protein shakes. Mounjaro (tirzepatide) is a dual GIP and GLP-1 receptor agonist licensed for weight management — clinical trials showed participants lost an average of 15–21% of their body weight over 72 weeks when used with a reduced-calorie diet. Wegovy (semaglutide) is a GLP-1 injection that helped participants lose approximately 15% of body weight in trials. Saxenda (liraglutide) is a daily GLP-1 injection with similar evidence. All three are prescription-only medicines requiring clinical assessment. Eligibility includes: BMI of 30 or above, or BMI of 27–29.9 with weight-related health conditions like type 2 diabetes, high blood pressure, or cardiovascular disease. For South Asian, Chinese, Black African, or Black Caribbean adults, lower thresholds apply (BMI 27.5+). Individual results vary significantly — these medications work best alongside dietary changes and increased physical activity, not instead of them.
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 — How to Find Out If You're Eligible
In the UK, prescription weight loss treatment is available through two routes. NHS access is through tier 3 specialist weight management services — ask your GP for a referral, though waiting lists vary significantly by region and can be lengthy. Private access is through GPhC-registered online pharmacies following an online clinical assessment with a UK-licensed prescriber, without needing NHS referral. Either route requires a prescriber to assess your individual health and confirm suitability. Use our free BMI calculator above to check your personal BMI — this will help you understand if you meet the basic eligibility criteria. Your GP can discuss which route (NHS or private) is most appropriate for you and whether prescription medication, combined with breakfast protein intake and overall weight management strategies, would help your specific situation.
- 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 protein shake for breakfast alone help me lose weight?
Protein shakes at breakfast can support weight loss by increasing satiety and reducing calorie intake later in the day. However, sustainable weight loss requires an overall calorie deficit, increased physical activity, and consistent healthy choices. For some people, adding prescription weight loss medication alongside dietary changes produces better results. Your GP can advise on the best approach for you.
Who is eligible for prescription weight loss medication in the UK?
Adults with a BMI of 30 or above, or 27–29.9 with weight-related health conditions (type 2 diabetes, high blood pressure, cardiovascular disease, sleep apnoea), may be eligible. For South Asian, Chinese, Black African, or Black Caribbean adults, lower thresholds apply. A prescriber will assess your individual health to confirm suitability.
How much weight can I expect to lose with Mounjaro or Wegovy?
Clinical trials showed average weight loss of 15–21% with Mounjaro and approximately 15% with Wegovy over several months — but individual results vary significantly. These medications work best alongside a reduced-calorie diet and increased physical activity. Your actual weight loss depends on your starting weight, adherence, and lifestyle changes.
How do I access weight loss medication on the NHS in the UK?
Ask your GP for a referral to a tier 3 specialist weight management service in your area. NHS access is available but waiting lists vary by region and can be lengthy. Alternatively, you can access prescription weight loss medication privately through an online clinical assessment with a GPhC-registered pharmacy — this does not require NHS referral.
Are prescription weight loss injections safe?
Mounjaro, Wegovy, and Saxenda are prescription-only medicines approved by the MHRA for safe use in the UK. Like all medications, they have side effects — nausea and digestive changes are common initially. A prescriber will assess whether the medication is safe and suitable for your health. Always discuss any concerns with your GP or 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.