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 Tips from the NHS
Losing weight sustainably doesn't require extreme measures. The NHS recommends a practical, evidence-based approach combining lifestyle changes with professional support. For eligible adults, prescription weight loss medication is now available on the NHS and through private prescribing, making weight management more achievable than ever. This guide covers the most effective weight loss tips, how to track your progress, and what medication options are available if you need additional support.
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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 Weight Loss Medication Options
If lifestyle changes alone aren't working, prescription weight loss medication is available in the UK for eligible adults. Three main options are licensed for weight management:
- Mounjaro (tirzepatide) — a once-weekly injection that works via dual GIP and GLP-1 pathways, helping reduce appetite and support feeling fuller. Clinical trials showed average weight loss of 15–21% of body weight over 72 weeks.
- Wegovy (semaglutide) — a once-weekly GLP-1 injection that may help with appetite control and portion sizes. Average weight loss shown was approximately 15% of body weight.
- Saxenda (liraglutide) — a daily GLP-1 injection, typically used when once-weekly options aren't suitable.
You're eligible if your BMI is 30 or above, or 27 or above with weight-related health conditions (such as type 2 diabetes, high blood pressure, or sleep apnoea). Individual results vary significantly — medication works best alongside a reduced-calorie diet and increased physical activity.
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.
Getting Started: NHS vs Private Routes
In the UK, you can access weight loss medication through two main routes. The NHS route involves a referral from your GP to a specialist tier 3 weight management service — availability varies significantly by region and waiting times can be substantial. The private route involves an online consultation with a UK-licensed prescriber; if approved, medication is dispensed by a GPhC-registered pharmacy without needing an NHS referral.
Start by speaking with your GP about whether prescription weight loss treatment might be suitable for you. They can assess your individual health, discuss your weight management goals, and guide you toward the right option. Use our free BMI calculator above to check your current BMI, and our GLP-1 weight loss calculator to estimate potential results at different medication doses.
Use our free progress tracker to log your weight weekly — tracking helps maintain motivation and identify patterns. The NHS recommends a sustainable loss of 0.5–1 kg per week; faster loss increases muscle loss risk. Combine any medication with a reduced-calorie diet (typically 500 kcal deficit daily) and regular physical activity for best results. Weight loss is rarely linear — expect fluctuations and plateaus; this is normal.
Our weight converter makes it easy to track progress in stone, kilograms, or pounds, whichever feels most natural. Consider keeping a food diary or using a calorie-tracking app alongside medication to support your goals. Remember that weight loss medication is a tool, not a substitute for lifestyle change — the most sustainable results come from combining medical support with behaviour change.
- 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 are the NHS recommended weight loss tips?
The NHS recommends a calorie deficit of 500 kcal per day for gradual, sustainable loss of around 0.5–1 kg weekly. Focus on whole foods, increase vegetables and protein, reduce sugary drinks, and aim for 150 minutes of moderate activity per week. For many people, combining these lifestyle changes with prescription weight loss medication produces better results than either approach alone.
Am I eligible for weight loss medication on the NHS?
You may be eligible if your BMI is 30 or above, or 27 or above with weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea. Eligibility is assessed individually — speak with your GP, who can refer you to specialist weight management services. Ethnicity-adjusted thresholds may apply; for South Asian, Black African, Caribbean, and Chinese adults, lower BMI thresholds are recommended.
How much weight can I lose with Mounjaro or Wegovy?
Clinical trials showed average weight loss of 15–21% of body weight with Mounjaro and approximately 15% with Wegovy over 72 weeks, alongside diet and activity changes. However, individual results vary significantly — some people lose more, some less. Use our free GLP-1 weight loss calculator to estimate potential results based on your starting weight and dose.
What's the difference between NHS and private weight loss medication access?
NHS access requires a GP referral to specialist tier 3 services; availability and waiting times vary by region. Private access involves an online consultation with a UK-licensed prescriber and dispensing by a GPhC pharmacy, without NHS referral. Both routes require clinical assessment — you cannot obtain prescription weight loss medication without a prescription.
How do I track weight loss effectively?
The NHS recommends weekly weighing at the same time of day, in similar clothing. Use our free progress tracker to log results consistently. Weight fluctuates due to water retention, hormones, and digestion — focus on the overall trend rather than daily changes. Combine weighing with measurements (waist circumference) and how clothes fit for a fuller picture of progress.
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.