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 Is A Healthy BMI For Men?
A healthy BMI for men in the UK is between 18.5 and 24.9, according to NHS guidelines. BMI (Body Mass Index) is calculated by dividing your weight in kilograms by your height in metres squared, and it's a useful screening tool that your GP uses to assess whether your weight is healthy for your height. However, it's important to understand that BMI has limitations — it doesn't distinguish between muscle and fat, so athletes or very muscular men may have a higher BMI without excess body fat. You can calculate your personal BMI now using our free BMI calculator above to see where you fall on the NHS scale.
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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
The NHS uses standardised BMI categories to assess weight status in adult men. These categories help your GP identify health risks and determine whether lifestyle changes or medical support might be needed.
- Under 18.5: Underweight — may indicate nutritional deficiency or other health concerns
- 18.5 to 24.9: Healthy weight — the target range for most men
- 25.0 to 29.9: Overweight — increased risk of weight-related health conditions
- 30.0 to 34.9: Obese (Class I) — higher health risks including type 2 diabetes and heart disease
- 35.0 to 39.9: Obese (Class II) — significantly elevated health risks
- 40.0 and above: Severely obese (Class III) — very high health risks requiring medical assessment
If you're a man of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends lower BMI thresholds due to higher cardiovascular and diabetes risk at the same BMI. For these groups, a healthy BMI starts at 18.5 and extends to 22.9, with overweight beginning at 23.0. Your GP can discuss which categories apply to you based on your ethnicity and individual health profile.
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 When To Speak With Your GP
If your BMI falls outside the healthy range, the NHS offers a structured weight management pathway to help. At tier 1, you can access free digital tools, community programmes, and the NHS Weight Loss Plan — all available without needing a GP referral. If you need more support, your GP can refer you to tier 2 primary care interventions or tier 3 specialist weight management services, where additional options including prescription medications may be considered.
The NHS recommends losing weight gradually at a rate of 0.5 to 1 kg per week alongside a reduced-calorie diet and increased physical activity. Weight loss is often most effective when combined with behaviour change support. If you have weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea, speak with your GP about personalised support — they can assess your individual needs and discuss what options are available to you through the NHS.
- 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.
How do I calculate my BMI?
BMI is calculated by dividing your weight in kilograms by your height in metres squared. For example, if you weigh 80kg and are 1.75m tall, your BMI is 80 ÷ (1.75 × 1.75) = 26.1. You can use our free BMI calculator above to calculate this instantly.
Is a BMI of 25 overweight?
Yes, according to NHS guidelines, a BMI of 25.0 to 29.9 is classified as overweight. This doesn't necessarily mean you need to lose weight immediately, but it's worth discussing with your GP, especially if you have other health risk factors like high blood pressure or a family history of heart disease.
What if I'm very muscular — is a high BMI still a health concern?
BMI has limitations and doesn't distinguish between muscle and fat. If you're very muscular or athletic, a higher BMI may not reflect excess body fat. Your GP can assess other factors like waist circumference and fitness level to give you a more complete picture of your health.
At what BMI should I see my GP about weight?
You can speak with your GP about weight at any time if you're concerned. The NHS recommends seeking support if your BMI is 25 or above, particularly if you have weight-related health conditions. Your GP can help you decide whether lifestyle changes, digital support, or specialist referral would be beneficial.
Can I use the weight converter to check if my weight is healthy?
Yes. Use our free weight converter above to switch between kilograms, stone, and pounds, then use the BMI calculator to check where your weight falls on the NHS healthy weight range for your height. This gives you a complete picture of your personal BMI status.
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.