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
Does Creatine Help With Weight Loss?
Creatine is a popular supplement among gym-goers, but it's not a weight loss tool. In fact, creatine typically increases water retention and body weight in the short term. If you're looking to lose weight in the UK, prescription weight management options like Mounjaro and Wegovy are evidence-backed alternatives that actually support weight loss. Our GLP-1 weight loss calculator can help you explore potential outcomes with these medications. Read on to understand what creatine does, why it won't help you lose weight, and what clinically proven options are available through the NHS or private prescribing.
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 Loss Options That Actually Work
If weight loss is your goal, prescription medications are far more effective than supplements like creatine. The NHS and private prescribers in the UK offer three licensed options for eligible adults:
- Mounjaro (tirzepatide) — A dual GIP and GLP-1 receptor agonist injection. Clinical trials showed participants lost an average of 15–21% of their body weight over 72 weeks, alongside a reduced-calorie diet and increased physical activity.
- Wegovy (semaglutide) — A GLP-1 receptor agonist injection. In the STEP-1 trial, participants lost approximately 14.9% of their body weight at 68 weeks on the maximum dose.
- Saxenda (liraglutide) — Another GLP-1 option, administered as a daily injection rather than weekly.
These medications work by regulating appetite and supporting sustainable weight loss when combined with lifestyle changes. Try our free weight loss calculator above to estimate potential outcomes at different doses.
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 in the UK
Access to prescription weight loss medication in the UK depends on eligibility and your preferred route. Through the NHS, you'll need referral to a tier 3 specialist weight management service from your GP. Availability varies significantly by region, and waiting lists can be lengthy. Alternatively, private online prescribing offers faster access — you complete a clinical assessment with a UK-licensed prescriber, and if suitable, receive a prescription dispensed by a GPhC-registered pharmacy. To find out if you're eligible, calculate your BMI using our free BMI calculator above. Adults with a BMI of 30 or above (or 27+ with weight-related health conditions like type 2 diabetes or high blood pressure) may qualify. Chat with your GP about your options.
- 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.
Does creatine cause weight loss?
No. Creatine actually causes short-term weight gain due to increased water retention in muscles. It's designed to improve athletic performance and muscle strength, not weight loss. If your goal is to lose weight in the UK, prescription medications like Mounjaro or Wegovy are evidence-backed options.
What's the difference between creatine and weight loss injections?
Creatine is a supplement that supports muscle function and athletic performance. Weight loss injections like Mounjaro and Wegovy are prescription medications that regulate appetite and support sustainable weight loss alongside diet and exercise. They work through different mechanisms entirely.
Can I take creatine while using Mounjaro or Wegovy?
Creatine is generally safe to use alongside prescription weight loss medications, but you should always inform your prescriber of all supplements you're taking. They can assess any potential interactions and give personalised advice based on your health.
How much weight can I lose with UK prescription medication?
Clinical trial results show average weight loss of 15–21% of body weight with Mounjaro and approximately 15% with Wegovy over several months. However, individual results vary significantly based on dose, adherence, diet, and physical activity. Use our weight loss calculator to see estimated outcomes.
How do I get weight loss medication on the NHS in the UK?
Speak to your GP about referral to a specialist weight management service (tier 3). Eligibility is based on BMI (30+, or 27+ with weight-related conditions). NHS availability varies by region. Private prescribing offers an alternative route without waiting for NHS referral.
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.