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
Understanding Male Obesity and Health Risk
Male obesity is defined as a BMI of 30 or above and affects around 1 in 3 UK men. Being obese significantly increases the risk of serious health conditions including type 2 diabetes, heart disease, and certain cancers. The good news is that even modest weight loss—as little as 5–10% of body weight—can meaningfully improve health outcomes. Our free BMI calculator above can help you check where you stand, and your GP can provide personalised guidance on next steps for your individual health.
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 Conditions Linked to Male Obesity
Research from the NHS and Public Health England shows that obese men face significantly elevated risks for serious health conditions. Men with a BMI above 30 are at substantially higher risk of type 2 diabetes (up to 80 times higher at severe obesity), high blood pressure, abnormal cholesterol levels, and cardiovascular disease including heart attack and stroke. Obstructive sleep apnoea—a condition where breathing repeatedly stops during sleep—is also strongly linked to excess weight in men. Additionally, obesity increases the risk of 13 types of cancer, including bowel, prostate, and liver cancer. Men with excess abdominal fat face particularly high risk; the NHS recommends that men keep their waist measurement below 94cm (37 inches) to reduce health risk, with above 102cm (40 inches) indicating significantly elevated risk. These aren't scare statistics—they're evidence that supports action, and weight loss can reverse or significantly reduce many of these risks.
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 Support: NHS Pathway and Weight Management Options
If you're concerned about your weight and health, your GP is the best starting point. The NHS offers a structured weight management pathway: Tier 1 includes self-help resources and the free NHS Weight Loss Plan; Tier 2 involves primary care-based behaviour change programmes; and Tier 3 provides specialist multidisciplinary weight management services where prescription weight loss medication may be considered. For men with a BMI of 30 or above, or BMI of 27–29.9 with weight-related health conditions like diabetes or high blood pressure, prescription options including GLP-1 injections (such as Mounjaro or Wegovy) may be available through specialist services. Our free weight loss calculator can help you explore potential outcomes. Weight loss works best alongside sustainable lifestyle changes—reduced-calorie diet and increased physical activity—whether or not medication is used.
- 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 BMI counts as obese for men?
According to NHS guidelines, a BMI of 30 or above is classified as obese. You can check your personal BMI using our free BMI calculator above. At a given height, this typically means specific weight thresholds—for example, a man who is 5ft 10in (178cm) tall and weighs 90kg (14st 2lbs) would have a BMI of approximately 29.1 (overweight category). Your GP can discuss what your BMI means for your individual health.
Can weight loss reverse the health risks of obesity?
Yes. Evidence shows that losing even 5–10% of body weight can meaningfully improve blood pressure, blood sugar control, and reduce cardiovascular risk. Larger weight losses produce greater health improvements. The NHS encourages gradual, sustainable weight loss of 0.5–1kg per week. Lifestyle changes—diet and physical activity—form the foundation, and for eligible men, prescription weight loss medication may support additional loss.
Is my waist measurement important if I have a healthy BMI?
Yes. Waist measurement is an important health indicator independent of BMI. The NHS recommends men keep waist measurements below 94cm (37 inches); above 102cm (40 inches) indicates significantly elevated cardiovascular and diabetes risk. Excess abdominal fat is particularly associated with health problems even at lower BMI levels, so it's worth checking alongside BMI.
How do I access weight management support through the NHS?
Start by speaking to your GP, who can assess your health and discuss next steps. They may refer you to Tier 2 or Tier 3 weight management services depending on your BMI and health conditions. Tier 3 services are specialist multidisciplinary teams where prescription medications and intensive support are available. Availability and waiting times vary by region.
What weight loss medications might be available for men with obesity?
GLP-1 receptor agonist injections (Mounjaro and Wegovy) are prescription-only medications licensed in the UK for men with BMI 30 or above, or BMI 27–29.9 with weight-related health conditions. These are available through NHS specialist services or private prescribing following clinical assessment. Our free GLP-1 weight loss calculator can help you explore potential outcomes if you're considering medication.
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.