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
Balanced Diet Plan for Weight Loss — UK Health Guide
A balanced diet is the foundation of sustainable weight loss in the UK. Rather than restrictive fad diets, evidence shows that eating a variety of nutritious foods in the right portions — combined with physical activity — helps you lose weight steadily and keep it off. This guide explains the key principles of healthy eating for weight management, and how prescription weight management options are available for eligible adults who need additional support alongside diet and lifestyle changes.
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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
If you're struggling to lose weight through diet alone, prescription weight loss medications are available in the UK for eligible adults. The most commonly prescribed options include Mounjaro (tirzepatide), a once-weekly injection that works on two natural hormones to reduce appetite; Wegovy (semaglutide), another once-weekly GLP-1 injection; and Saxenda (liraglutide), a daily injection. In clinical trials, these medications helped participants lose an average of 15–21% of their body weight alongside a reduced-calorie diet and increased physical activity — though individual results vary significantly.
- Eligibility: Adults with a BMI of 30 kg/m² or above, or 27 kg/m² or above with weight-related health conditions (such as type 2 diabetes, high blood pressure, or sleep apnoea)
- Prescription requirement: All weight loss injections are prescription-only and require a clinical assessment from a licensed prescriber
- Dual approach: These medications are used alongside a balanced diet and physical activity — not as a replacement for lifestyle changes
Try our GLP-1 weight loss calculator to see how these medications might support your weight loss journey, and calculate your BMI using our free tool to check your eligibility.
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 Next Steps
In the UK, prescription weight loss medications are available through two routes. NHS access is through specialist tier 3 weight management services — your GP can refer you, though waiting lists vary significantly by region and may be lengthy. Private access is available through GPhC-registered online pharmacies following an online clinical assessment, without needing an NHS referral. Either way, a prescriber will assess whether medication is suitable for you based on your individual health.
Start by speaking with your GP about your weight management goals. They can discuss whether a balanced diet and lifestyle changes alone might be sufficient, or whether you could benefit from prescription support. You can also check your BMI and healthy weight range using our free calculator — this information helps your GP assess the right approach 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.
Is a balanced diet alone enough for weight loss?
For many people, a balanced diet with a calorie deficit of around 500 kcal per day, combined with physical activity, does support sustainable weight loss of 0.5–1 kg per week. However, if you've struggled with diet alone, prescription weight loss medications are available on the NHS or privately in the UK for eligible adults.
What counts as a balanced diet for weight loss?
A balanced diet includes plenty of vegetables, fruits, lean proteins (chicken, fish, pulses), whole grains, and healthy fats from sources like olive oil and nuts. Portion control is key — aim for a moderate calorie deficit without cutting out entire food groups. Your GP or a registered dietitian can provide personalised guidance.
How quickly can I expect to lose weight?
The NHS recommends losing weight at a rate of 0.5–1 kg (1–2 lbs) per week for sustainable results. Even a 5–10% reduction in body weight can bring meaningful health benefits, such as lower blood pressure and improved blood sugar control. With prescription medication alongside diet, some people see faster weight loss, though results vary widely.
Can I get weight loss injections on the NHS?
Yes, Mounjaro and Wegovy are available through NHS specialist weight management services. Access is by GP referral to tier 3 services, and availability depends on your local ICB. Private prescription is also available through online assessments. Either way, a prescriber must assess your eligibility first.
What's the difference between Mounjaro and Wegovy?
Mounjaro (tirzepatide) is a dual GIP and GLP-1 receptor agonist, while Wegovy (semaglutide) is a GLP-1 agonist only. Both are once-weekly injections licensed in the UK for weight management. Clinical trials show similar average weight loss (15–21% body weight), but individual responses vary. Your prescriber will advise which is most suitable for you.
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.