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
Obesity NHS Treatment — Support and Options Available
Obesity is a significant health concern in the UK, affecting millions of adults. If you're concerned about your weight, the NHS offers support through its tiered weight management pathway. Understanding the health risks linked to excess weight, the obesity UK thresholds, and what treatment options are available can help you take the right steps. Our free BMI calculator above lets you check where you stand against NHS healthy weight ranges instantly.
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.
Health Risks Linked to Excess Weight
Carrying excess weight increases the risk of developing serious health conditions. People with obesity face significantly higher risks of type 2 diabetes — up to 80 times higher at severe obesity — cardiovascular disease, high blood pressure, and abnormal cholesterol levels. The condition is also linked to 13 types of cancer, obstructive sleep apnoea, joint pain from osteoarthritis, and non-alcoholic fatty liver disease.
In the UK, approximately 28% of adults are obese (BMI 30 or above), and research shows that excess weight contributes to roughly 1 in 13 deaths. Even modest weight loss — as little as 5% of your body weight — may reduce blood pressure, improve blood sugar control, lower cholesterol, and ease joint pain. Using our weight converter, you can quickly translate your weight into different units to understand your current position against healthy weight ranges for your height.
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 Obesity Treatment Pathway and Options
The NHS offers a four-tier weight management pathway. Tier 1 involves self-help tools and community weight management programmes. Tier 2 provides primary care support and behaviour change programmes. Tier 3 is specialist multidisciplinary weight management services, where prescription medication may be considered for eligible adults. Tier 4 covers bariatric surgery for severe obesity with significant health complications.
For prescription treatment, eligibility typically requires a BMI of 30 or above, or 27–29.9 with weight-related health conditions. Our GLP-1 weight loss calculator can help eligible adults understand potential outcomes with prescription medications. Accessing treatment usually starts with a conversation with your GP, who can assess your individual situation and refer you to specialist services where available — though waiting lists and regional variation exist across the UK.
- 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 counts as obesity in the NHS?
According to NHS guidelines, obesity is defined as a BMI of 30 or above. However, for adults of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends lower thresholds — obesity starts at BMI 27.5 or above for these groups. Your GP or our free BMI calculator can determine your personal classification.
How much weight do I need to lose to see health benefits?
Research shows that losing just 5–10% of your body weight can have meaningful health benefits, including lower blood pressure, improved blood sugar control, and reduced joint pain. The NHS recommends aiming for a sustainable rate of 0.5–1 kg per week. Even modest progress counts.
Can I get obesity treatment through the NHS?
Yes. You can start by speaking to your GP, who may refer you to tier 2 or tier 3 weight management services depending on your circumstances and local availability. Prescription weight loss treatments are available through NHS specialist services, though waiting times and access vary significantly across different UK regions.
What if I can't get NHS treatment quickly?
If NHS waiting lists are long in your area, private prescription weight loss treatment is available through UK-licensed online prescribers following a clinical assessment. This requires a valid prescription but does not depend on NHS referral. Both pathways require individual assessment and clinical judgment.
Is weight loss medication used instead of diet and exercise changes?
No. Weight loss medications are used alongside reduced-calorie diet and increased physical activity, not as a replacement. Lifestyle changes remain the foundation of sustainable weight management. Medications can support these efforts but work most effectively as part of a comprehensive approach.
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.