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
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Age Weight Chart for UK Adults
An age weight chart shows healthy weight ranges based on age and height, helping you understand whether your weight falls within a healthy level for your age group. However, age alone isn't the best indicator of health — height, muscle mass, and overall fitness matter more. The NHS recommends using BMI (body mass index) combined with waist circumference as better tools for assessing healthy weight at any age. This guide explains what healthy weight means in the UK, how age affects weight expectations, and how to find your personal healthy range using NHS-aligned measurements.
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.
Understanding Healthy Weight Across Different Ages
The concept of an "ideal weight" for a specific age is less useful than you might think. Healthy weight depends primarily on height, not age. However, age does affect body composition — we naturally lose muscle and gain fat as we age, which changes how much we should weigh at the same height. The NHS uses BMI (body mass index) as the primary screening tool, which applies to all adults regardless of age.
NHS healthy weight range: BMI of 18.5 to 24.9 for most UK adults. For South Asian, Chinese, Black African, or Black Caribbean adults, a lower range of 18.5 to 22.9 is recommended due to higher health risks at lower BMI levels.
- At 25–29.9 BMI: overweight category
- At 30+ BMI: obese category
- Waist circumference also matters: men over 94cm (37 inches) and women over 80cm (31.5 inches) have increased health risk
Rather than following an age-specific weight chart, use our free BMI calculator above to find your personal healthy weight range based on 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.
Why Age-Specific Weight Charts Can Be Misleading
Traditional "age weight charts" often suggest that it's normal to gain weight with age. While some changes in body composition are natural, significant weight gain isn't inevitable and can increase health risks at any age. The NHS does not recommend age-specific weight targets — instead, health outcomes improve when weight stays within a healthy BMI range regardless of age.
Research shows that maintaining a healthy weight throughout life — not just in youth — reduces the risk of type 2 diabetes, cardiovascular disease, and certain cancers. Older adults who maintain a healthy weight have better mobility, independence, and quality of life than those with excess weight.
Use our weight converter and BMI calculator to establish your personal healthy weight range in stone, pounds, or kilograms.
- 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 is a healthy weight for my age?
Healthy weight depends on height, not age. Use your height to calculate a healthy BMI range (18.5–24.9) using the BMI calculator above. For example, a 5ft 8in adult with a healthy BMI weighs between 55–75kg (8st 10lbs–11st 10lbs). Your GP can also discuss what's healthy for you individually.
Should I expect to gain weight as I get older?
No. While body composition changes with age (some natural loss of muscle), significant weight gain isn't inevitable and increases health risks. The NHS recommends maintaining a healthy BMI across all ages to reduce diabetes, heart disease, and cancer risk.
Is BMI accurate for older adults?
BMI is less accurate in older age because it doesn't account for muscle loss. However, it remains a useful screening tool. Waist circumference is also important: over 94cm (men) or 80cm (women) indicates increased health risk. Your GP can assess your individual health profile.
What's the difference between healthy weight and ideal weight?
Healthy weight is a range (your BMI 18.5–24.9) calculated from height. "Ideal weight" is a personal target within that range. Both depend on factors like muscle mass and frame size, not age. Use our BMI calculator to find your healthy range.
Can I check my healthy weight progress with a tool?
Yes. Our free BMI calculator shows your healthy range instantly. Our free weight converter switches between stone, pounds, and kilograms. For long-term tracking, use our progress tracker to log weight changes and see trends over time.
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.