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
Free Nutrition Plan For Weight Loss in the UK
A nutrition plan is one of the most effective foundations for sustainable weight management in the UK. Whether you're aiming to reach a healthy weight or managing weight loss alongside medication, having a structured approach to nutrition makes a real difference. The NHS recommends combining dietary changes with increased physical activity for the best long-term results. If you're curious about your current BMI weight loss progress, our free tools can help you track where you are and set realistic goals. This guide covers evidence-based nutrition strategies, NHS weight management guidance, and how prescription options like Mounjaro and Wegovy fit into a comprehensive weight management plan.
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 Weight Management Options and Nutrition
If you have a BMI of 30 or above (or 27 or above with weight-related health conditions), you may be eligible for prescription weight loss medication in the UK. The most commonly prescribed options are:
- Mounjaro (tirzepatide) — a dual GIP/GLP-1 receptor agonist, once-weekly injection. Clinical trials showed average weight loss of 15–21% of body weight over 72 weeks when combined with nutrition and lifestyle changes.
- Wegovy (semaglutide) — a GLP-1 receptor agonist, once-weekly injection. Average weight loss was approximately 15% of body weight in clinical trials.
- Saxenda (liraglutide) — a daily GLP-1 injection, less commonly prescribed but still available.
These prescription medications work best alongside a structured nutrition plan, not instead of it. They help reduce appetite and support portion control, but dietary changes remain essential. Try our GLP-1 weight loss calculator to understand how prescription medication might fit into your weight management strategy. Your GP or a licensed prescriber will assess whether medication is suitable for you based on your individual health.
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 Guidance and How to Get Started
The NHS recommends a sustainable approach: aim to lose 0.5–1 kg per week through a combination of a calorie deficit (typically 500 kcal/day) and regular physical activity. A balanced nutrition plan should include whole grains, lean proteins, vegetables, and healthy fats while reducing sugary drinks and processed foods.
Access to prescription medication: In England, Wales, Scotland, and Northern Ireland, weight loss medication is available through NHS specialist weight management services (tier 3) or privately through online prescribing. NHS access varies by region and waiting lists can be lengthy. Private prescribing is faster but involves a cost. Your GP can discuss which route suits you best and whether you meet eligibility criteria. Use our BMI calculator to check your current BMI and understand where you sit on NHS eligibility thresholds. Even a 5% reduction in body weight can bring meaningful health improvements.
- 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.
What should a free nutrition plan for weight loss include?
A balanced nutrition plan includes lean proteins, whole grains, plenty of vegetables, healthy fats, and adequate water. Portion control and meal planning help create a sustainable calorie deficit. The NHS recommends losing 0.5–1 kg per week. Your GP or a registered dietitian can personalise a plan for your specific health needs and preferences.
Can I get a free nutrition plan from the NHS?
Yes. Your GP can refer you to free NHS weight management services, which often include dietitian support and behaviour change programmes. These are available across the UK, though waiting times vary by region. Private nutrition plans are also available but involve cost. Your GP is the best starting point for discussing free options in your area.
Should I use prescription weight loss medication alongside a nutrition plan?
Yes. Prescription medications like Mounjaro and Wegovy are designed to be used alongside a nutrition plan and increased physical activity, not instead of them. Medication helps reduce appetite, making it easier to stick to dietary changes. Your prescriber will discuss how to integrate medication with your nutrition strategy for best results.
How do I know if I'm eligible for weight loss medication in the UK?
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, high blood pressure, or sleep apnoea. Eligibility varies slightly by ethnicity — lower thresholds apply for South Asian, Chinese, Black African, and Black Caribbean adults. Your GP or a licensed prescriber can assess your eligibility.
What's the difference between NHS and private weight loss medication access in the UK?
NHS medication is free but accessed through specialist services with potential waiting lists of months. Private medication is faster and doesn't require NHS referral but involves costs (typically £129–£320/month depending on dose). Both require a clinical assessment. Your GP can explain both options and help you decide which suits your situation.
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.