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 the 5 App and How Does It Support UK Health?
The 5 App is a popular UK health and fitness tracking application designed to help users monitor their weight, activity levels, and overall wellness. For anyone managing their weight or tracking progress towards a healthier lifestyle in line with NHS guidance, understanding how such tools work is essential. Whether you're interested in weight management, fitness monitoring, or simply keeping track of daily health metrics, learning about app-based health trackers can complement traditional approaches like GP consultations and structured weight management programmes. This guide explains what the 5 App offers and how it fits into the broader UK health and wellness landscape.
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.
How the 5 App Works in UK Health Management
Health and fitness tracking apps like the 5 App are designed to help UK users monitor progress towards healthier weight and lifestyle goals. These applications typically allow you to log daily activities, track water intake, record meals, and monitor weight changes over time. Many apps sync with wearable devices to capture step counts and activity data automatically.
When used alongside healthy weight management strategies, tracking apps can provide motivation through visual progress charts and reminders. The NHS encourages using evidence-based tools to support sustainable lifestyle change, and digital trackers can be helpful additions to this approach. However, apps are most effective when used as part of a comprehensive plan that includes a balanced diet, regular physical activity, and where appropriate, support from your GP or a specialist weight management service.
For users interested in detailed monitoring, our free progress tracker on MyWeightCheck allows you to log weight changes and visualise your journey over time, complementing whatever app you choose to use.
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.
Using Apps Safely: NHS-Aligned Guidance for UK Users
While health tracking apps can be motivational, the NHS emphasises that sustainable weight loss requires more than app tracking alone. Losing weight at a rate of 0.5 to 1 kg per week is considered sustainable and safe by UK health guidance. Apps should support this process, not drive unsafe gradual weight management targets.
Before relying heavily on any health app, especially if you have underlying health conditions or are taking medications, discuss your plan with your GP. If you're interested in understanding whether your current weight is healthy for your height, use our free BMI calculator to get an NHS-aligned assessment instantly. Some users also benefit from specialist tier 3 weight management services available through the NHS, which provide evidence-based support beyond app tracking.
- 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 the 5 App approved by the NHS?
The 5 App is a commercial health tracking tool. While the NHS recommends using digital health support, the 5 App itself is not an official NHS service. Always consult your GP before starting any new health programme, whether app-based or not.
Can a health app help me lose weight?
Health apps can support weight loss by helping you track progress and maintain motivation. However, sustainable weight loss requires a calorie deficit, regular physical activity, and dietary changes. Apps are most effective when combined with these lifestyle changes, not used alone.
What's a healthy weight loss rate in the UK?
The NHS recommends losing 0.5 to 1 kg (1 to 2 lbs) per week for safe, sustainable weight loss. Faster weight loss can lead to muscle loss and is not recommended without medical supervision.
Should I use an app instead of seeing my GP?
No. Apps are tools that can complement professional healthcare, not replace it. If you have concerns about your weight or health, always speak to your GP first. They can refer you to appropriate support services in your area.
How do I know if my current weight is healthy?
Use our free BMI calculator on this page to get an instant NHS-aligned assessment. A BMI between 18.5 and 24.9 is considered healthy for most adults, though ethnicity-specific thresholds apply. Your GP can provide personalised guidance.
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.