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
What Does a BMI of 37 Mean for Your Health?
A BMI of 37 puts you in the obese (Class II) category according to NHS guidelines. This BMI range is associated with increased health risks, but the good news is that even modest weight loss can have meaningful health benefits. Understanding where your BMI sits and what it means is the first step towards making informed health decisions. Use our free BMI calculator above to check your personal BMI and explore what support the NHS offers for weight management.
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.
NHS BMI Categories and What They Mean
According to NHS guidance, a BMI of 37 falls into the obese (Class II) category, which ranges from 35.0 to 39.9. The standard BMI formula divides your weight in kilograms by your height in metres squared. For context, here are the NHS BMI categories:
- Underweight: Below 18.5
- Healthy weight: 18.5 to 24.9
- Overweight: 25.0 to 29.9
- Obese (Class I): 30.0 to 34.9
- Obese (Class II): 35.0 to 39.9
- Severely obese (Class III): 40.0 and above
It's important to remember that BMI has limitations — it doesn't account for muscle mass or where fat is stored on your body. Your GP can provide personalised advice about what your individual BMI means for your health.
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 Weight Management Support and Your Next Steps
If you have a BMI of 37, the NHS recommends discussing your weight with your GP, who can assess your individual health and explore the right support for you. The NHS offers a structured weight management pathway across four tiers: self-help resources and community programmes (Tier 1), primary care-based interventions (Tier 2), specialist multidisciplinary weight management services (Tier 3), and bariatric surgery options (Tier 4). Tier 3 services may include prescription weight loss medications alongside dietary support and exercise guidance. Even a 5–10% reduction in body weight can improve blood pressure, blood sugar control, and reduce cardiovascular risk. Use the weight converter on this page to understand your weight in different units, and consider tracking your progress with our free progress tracker.
- 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 BMI of 37 considered obese?
Yes, a BMI of 37 falls in the obese (Class II) category according to NHS guidelines, which ranges from 35.0 to 39.9. This category is associated with increased health risks, but your GP can provide personalised advice about what this means for you individually.
What health risks are associated with a BMI of 37?
A BMI of 37 increases the risk of type 2 diabetes, cardiovascular disease, high blood pressure, sleep apnoea, and certain cancers. However, losing even 5–10% of your body weight can significantly reduce these risks and improve overall health outcomes.
What should I do if my BMI is 37?
Start by booking an appointment with your GP to discuss your weight and health. They can assess your individual situation, discuss the NHS weight management pathway, and explore support options ranging from lifestyle changes to specialist services or prescription medications if appropriate.
Can I use a BMI calculator to check my exact BMI?
Yes. Our free BMI calculator on this page instantly calculates your BMI using your weight and height. It also shows you which NHS category your BMI falls into and provides context for healthy weight ranges at your height.
Are there NHS treatments available for a BMI of 37?
Yes. The NHS offers weight management support through specialist services (Tier 3), which may include prescription medications like Mounjaro or Wegovy alongside dietary support and physical activity guidance. Access varies by region — your GP can advise on local availability and eligibility criteria.
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.