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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7 Days Weight Loss Meal Plan: UK Prescription Weight Management Options
A structured 7-day weight loss meal plan is most effective when combined with sustainable lifestyle changes and, where clinically appropriate, prescription support. In the UK, several weight management approaches are available to help you lose weight effectively. Our GLP-1 weight loss calculator can help you explore potential weight loss outcomes, whilst our BMI calculator lets you assess your current health status. This guide focuses on prescription weight management options available to eligible UK adults, how they work alongside meal planning, and how to access them through NHS or private routes.
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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 Management Options
Three prescription medications are licensed in the UK for weight management and can support structured meal plans:
- Mounjaro (tirzepatide) — dual GIP and GLP-1 receptor agonist, once-weekly injection, clinical trials showed average weight loss of 15–21% body weight over 72 weeks alongside reduced-calorie diet and activity
- Wegovy (semaglutide) — GLP-1 receptor agonist, once-weekly injection, clinical trials showed average weight loss around 15% body weight at 68 weeks
- Saxenda (liraglutide) — GLP-1 receptor agonist, daily injection, lower average weight loss but longer-established safety profile
Eligibility requires a BMI of 30 or above, or BMI 27–29.9 with weight-related health conditions such as type 2 diabetes, high blood pressure, or cardiovascular disease. For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, lower BMI thresholds may apply. These medications work by reducing appetite and supporting satiety — making it easier to stick to a calorie-controlled meal plan. Individual results vary significantly and depend on adherence to both medication and dietary 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: Getting Started in the UK
NHS route: Referral to a specialist tier 3 weight management service through your GP. This is free but availability and waiting times vary significantly by region — some areas have long waiting lists.
Private route: Online consultation with a UK-licensed prescriber through a GPhC-registered pharmacy. No NHS referral needed, faster access, though costs typically range from £129–£320 per month depending on dose.
Your first step is to contact your GP to discuss weight management options and your individual health. They can assess eligibility, discuss meal planning support, and refer you to NHS services if appropriate. Prescription weight loss medication is most effective when combined with a structured meal plan, regular physical activity, and behaviour change support.
- 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 I use a 7-day meal plan without prescription medication?
Yes. A structured meal plan with reduced-calorie intake (approximately 500 kcal deficit daily) can support steady weight loss of 0.5–1 kg per week. However, some people find prescription weight management medication helpful alongside meal planning to reduce appetite and improve compliance. Your GP can advise whether medication may benefit you.
How long does it take to see weight loss with Mounjaro or Wegovy?
Clinical trials showed measurable weight loss within 4–8 weeks of starting treatment, with continued loss over 12–16 weeks as doses are gradually increased. However, individual timelines vary. Most people reach maximum dose by week 16–20. Results depend on adherence to both medication and meal plan changes.
Will prescription weight loss medication work if I don't follow a meal plan?
Prescription medications work best when combined with reduced-calorie eating and increased physical activity. They support appetite control and satiety, making it easier to stick to a meal plan — but they are not a substitute for dietary changes. Think of them as a tool to help you succeed, not a replacement for healthy eating.
How do I know if I'm eligible for NHS prescription weight management?
You're typically eligible if you have a BMI of 30 or above, or 27–29.9 with weight-related health conditions. For South Asian and some other ethnic backgrounds, eligibility starts at BMI 27.5. Contact your GP to assess your individual eligibility and discuss referral to specialist services.
What's the difference between a meal plan and prescription medication?
A meal plan manages calorie intake and nutrition. Prescription medication (like Mounjaro or Wegovy) reduces appetite hormones, making it easier to stick to a reduced-calorie plan and feel satisfied with smaller portions. Together, they create a more comprehensive approach to weight management than either alone.
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.