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
Walking and Weight Loss — How It Works in the UK
Walking is one of the most accessible forms of physical activity for weight management in the UK. While regular walking alone can contribute to gradual weight loss when combined with a reduced-calorie diet, many people find that adding prescription weight loss medication to their routine produces more significant results. This guide covers walking for weight management, explores UK-licensed options available to eligible adults, and explains how to discuss your weight loss journey with your GP.
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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.
Prescription Weight Loss Options Available in the UK
For adults looking to lose weight in the UK, several prescription-only weight loss medications are available through NHS specialist services or private prescribing. These medications work by supporting appetite regulation and fullness, making them effective when combined with lifestyle changes like walking and dietary adjustment.
Current UK-licensed options include:
- Mounjaro (tirzepatide) — a dual GIP and GLP-1 receptor agonist, once-weekly injection. Clinical trials showed average weight loss of approximately 15–21% of body weight over 72 weeks.
- 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, typically resulting in around 5–clinically studied weight loss.
All require a prescription and clinical assessment to determine eligibility. Individual results vary significantly, and medication works best alongside physical activity (such as walking), dietary changes, and behaviour support.
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.
Eligibility and How to Access Weight Loss Support in the UK
To be eligible for prescription weight loss medication in the UK, you typically need a BMI of 30 or above, or 27 or above if you have weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea. Start by speaking with your GP, who can assess your individual situation and either refer you to an NHS specialist weight management service or discuss private options.
NHS access varies by region — waiting times can be significant in many areas. Private online prescribing offers faster access following an online clinical assessment. Whatever route you choose, weight loss medication is most effective when combined with walking, healthier eating, and consistent progress tracking. Use our free BMI calculator to check where you currently stand, and our GLP-1 weight loss calculator to explore potential outcomes with medication 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 walking alone help me lose weight?
Yes, regular walking contributes to weight loss when combined with a reduced-calorie diet. The NHS recommends 150 minutes of moderate activity per week. However, most people achieve faster, more significant results by adding dietary changes and, if eligible, prescription weight loss medication. Calculate your potential weight loss with our GLP-1 weight loss calculator.
What is the difference between Mounjaro and Wegovy?
Both are once-weekly injections for weight management. Mounjaro (tirzepatide) activates two hormone pathways (GIP and GLP-1), while Wegovy (semaglutide) activates one (GLP-1). Clinical trials suggest Mounjaro may produce slightly higher average weight loss, though results vary individually. A prescriber can advise which is more suitable for you.
How do I know if I'm eligible for prescription weight loss treatment?
Eligibility depends on your BMI and health conditions. Generally, adults with BMI 30+ or BMI 27–29 with weight-related conditions (diabetes, high blood pressure, sleep apnoea) may qualify. Use our free BMI calculator to check your current BMI, then speak with your GP about your options.
Can I take weight loss medication on the NHS?
Yes, NICE has approved tirzepatide (Mounjaro) for NHS use. Access is through specialist tier 3 weight management services, typically requiring a GP referral. Availability varies significantly by region and waiting times can be lengthy. Private prescribing offers faster access if you're eligible.
What should I do alongside taking weight loss medication?
Weight loss medication works best with regular physical activity (like walking), a reduced-calorie, balanced diet, behaviour changes, and progress tracking. Many people find that combining walking with medication produces better results than either alone. Track your progress with our free progress tracker to stay motivated.
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.