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
Healthy Eating For Weight Loss
Healthy eating is the foundation of sustainable weight loss. Rather than following restrictive crash diets, evidence-based nutrition helps you lose weight at a healthy rate whilst maintaining energy and overall wellbeing. The NHS recommends losing weight at 0.5 to 1 kg per week through a combination of balanced eating and physical activity. Understanding how to make nutritious food choices, manage portions, and build sustainable eating habits is key to achieving and maintaining a healthier weight. Whether you're managing your weight management uk through diet alone or alongside other interventions, the principles of healthy eating remain central to success.
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.
Evidence-Based Approaches to Healthy Eating for Weight Loss
Sustainable weight loss requires a calorie deficit — consuming fewer calories than your body burns — typically around 500 kcal per day to lose approximately 0.5 kg weekly. Rather than eliminating foods entirely, focus on nutrient-dense choices: lean proteins, whole grains, vegetables, and fruits. These foods are more filling and support stable blood sugar levels.
- Mediterranean diet: Strong evidence supports this approach for both weight loss and cardiovascular health, emphasising olive oil, fish, vegetables, and whole grains
- Reduced-calorie eating: Lowering overall intake by 20–30% whilst maintaining balanced nutrition
- Intermittent fasting: Some people find 16:8 or 5:2 approaches helpful, though results are similar to standard calorie restriction
- Protein intake: Higher protein supports muscle retention during weight loss and increases satiety — aim for lean meat, fish, eggs, and legumes
NHS weight loss guidance emphasises realistic, gradual changes rather than rapid restriction. The key is finding an approach you can sustain long-term rather than chasing quick results.
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.
Combining Healthy Eating With Other Weight Loss Strategies
Healthy eating is most effective when combined with physical activity — even 30 minutes of moderate exercise most days supports weight loss and improves health markers. For those seeking additional support, prescription weight loss medication like GLP-1 medications (such as Mounjaro or Wegovy) may help alongside dietary changes. These medications support reduced appetite and can complement healthy eating strategies when prescribed following clinical assessment. Track your progress using our free BMI calculator to monitor how dietary changes affect your weight and health markers. Remember, sustainable weight loss with nhs weight loss principles involves patience, consistency, and lifestyle changes rather than quick fixes — most people find success by making gradual improvements to eating habits rather than dramatic overhauls.
- 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 the best diet for weight loss?
There is no single "best" diet. Evidence supports Mediterranean, calorie-restricted, and low-carbohydrate approaches equally. The most effective diet is one you can sustain long-term. NHS guidance recommends choosing an approach that includes whole grains, lean proteins, vegetables, and fruits whilst maintaining a calorie deficit of around 500 kcal daily.
How quickly should I expect to lose weight?
NHS recommends losing 0.5 to 1 kg per week for safe, sustainable weight loss. Faster weight loss may result in muscle loss and nutrient deficiencies. Using our GLP-1 weight loss calculator can help you project realistic timelines if you're considering prescription weight loss medication alongside dietary changes.
Can I lose weight through diet alone without exercise?
Yes — weight loss fundamentally requires a calorie deficit, which diet can create independently. However, combining healthy eating with physical activity produces better health outcomes, helps preserve muscle mass, and supports cardiovascular health. Even modest activity like 30 minutes of walking daily amplifies results.
Should I eliminate carbohydrates to lose weight?
Eliminating carbohydrates is not necessary. Low-carbohydrate diets can produce weight loss, but the effect is mainly due to overall calorie reduction. Whole grains, beans, and vegetables are nutritious carbohydrate sources that support weight loss when portions are managed. NHS guidance supports balanced eating including carbohydrates.
How does prescription weight loss medication fit with healthy eating?
Prescription medications like Mounjaro and Wegovy are designed to complement, not replace, healthy eating and physical activity. These GLP-1 medications may help reduce appetite and support feeling fuller, making it easier to maintain a healthy diet. They require clinical assessment and prescription from a GP or licensed prescriber. Calculate your personalised bmi weight loss targets using our free BMI calculator to understand your baseline.
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.