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 57.9 Kg In Stone And What BMI Does It Give?
57.9 kg converts to approximately 9 stone 2 lbs in UK measurements. However, your BMI — and whether this weight is healthy for you — depends entirely on your height. The same weight gives very different BMI values at different heights, which is why height-specific assessment matters. Use our free BMI calculator above to check your personal BMI instantly by entering both your weight and height.
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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.
57.9 Kg In Stone At Different Heights — BMI Examples
To understand what 57.9 kg in stone means for your health, here are BMI examples at common UK heights. To convert kilograms to stone, we divide 57.9 by 6.35, giving approximately 9 stone 2 lbs.
- At 160 cm (5ft 3in): BMI = 22.6 — healthy weight (NHS range 18.5–24.9)
- At 165 cm (5ft 5in): BMI = 21.3 — healthy weight
- At 170 cm (5ft 7in): BMI = 20.0 — healthy weight
- At 175 cm (5ft 9in): BMI = 18.9 — healthy weight
- At 180 cm (5ft 11in): BMI = 17.9 — underweight (NHS range below 18.5)
At most average UK adult heights, 57.9 kg falls comfortably within the healthy weight range. Use the weight converter on this page to see this weight in different units.
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.
Understanding BMI Categories And Limitations
According to NHS guidelines, a BMI between 18.5 and 24.9 is considered healthy weight. BMI is a useful screening tool because it's quick and easy to calculate — but it has important limitations. BMI does not distinguish between muscle and fat, so athletes or very muscular individuals may have a high BMI despite low body fat. BMI also doesn't account for where fat is stored around your body. For a more complete picture of your health, your GP can also measure waist circumference and discuss your overall fitness and medical history alongside BMI.
- 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 convert 57.9 kg to stone and pounds?
Divide 57.9 by 6.35029 to get stone (9.13 stone), then multiply the decimal by 14 to get pounds. This gives approximately 9 stone 2 lbs. Alternatively, use our free weight converter above for instant conversion between kg, stone, and lbs.
Is 57.9 kg a healthy weight for an adult?
It depends on your height. At most average UK adult heights (5ft 3in to 5ft 9in), 57.9 kg gives a BMI in the healthy range (18.5–24.9). Your GP can advise on what's healthy for your individual circumstances, including muscle mass and medical history.
What if I'm of South Asian or Black African heritage — do BMI thresholds change?
Yes. The NHS recommends lower thresholds for people of South Asian, Chinese, Black African, and Black Caribbean backgrounds due to higher health risks at lower BMI levels. Healthy weight for these groups is BMI 18.5–22.9 instead of 18.5–24.9. Speak to your GP about what this means for you.
What does the BMI of 57.9 kg at different heights tell me?
At 160 cm, your BMI would be 22.6 (healthy). At 175 cm, it would be 18.9 (healthy). At 180 cm, it would be 17.9 (underweight). Use our free BMI calculator above to calculate your exact BMI by entering both your weight and height together.
Are there other ways to assess whether my weight is healthy besides BMI?
Yes. NHS guidance also recommends measuring waist circumference (increased risk over 80 cm for women, 94 cm for men). Fitness level, muscle mass, and overall health markers like blood pressure and cholesterol matter too. Your GP can give personalised advice beyond BMI alone.
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.