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
Foods to Consume for Weight Loss — What Works
Losing weight sustainably starts with eating the right foods, not necessarily eating less overall. The NHS recommends focusing on nutrient-dense, filling foods that support a calorie deficit without leaving you hungry. The best foods for weight loss are high in protein and fibre, low in calories, and keep your blood sugar stable. Combined with increased physical activity and behaviour changes, the right food choices can make weight loss feel manageable and lasting. Our free BMI calculator can help you understand your current weight context, while understanding what to eat is equally important.
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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.
Best Foods for Weight Loss in the UK
Protein-rich foods are your foundation. Lean meats (chicken, turkey), fish (especially oily fish like salmon), eggs, and legumes (lentils, chickpeas) help you feel fuller for longer and preserve muscle during weight loss. The NHS recommends including protein at every meal.
High-fibre foods — whole grains, vegetables (especially leafy greens, broccoli, peppers), beans, and fruit — slow digestion and reduce cravings. Fibre also supports healthy gut bacteria linked to weight management.
- Vegetables with minimal calories: spinach, kale, cabbage, cauliflower, courgettes
- Whole grains: brown rice, oats, quinoa, wholemeal bread
- Fruits with good fibre: berries, apples, pears (portion-controlled)
- Healthy fats: avocados, nuts, olive oil (in moderation)
Water is equally important — staying hydrated supports metabolism and can reduce mistaken hunger signals. The key is building meals around these foods rather than restricting calories drastically.
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.
Foods to Avoid and Practical Meal Building
Ultra-processed foods, sugary drinks, and high-calorie snacks provide little nutritional value and spike blood sugar, leading to energy crashes and increased cravings. The NHS encourages reading food labels and being aware of hidden sugars and excess salt.
A practical approach: fill half your plate with vegetables, a quarter with lean protein, and a quarter with whole grains or starchy vegetables. This ratio naturally creates a calorie deficit whilst keeping you satisfied. Meal planning and preparing food at home gives you control over ingredients. If you're considering weight loss medication like GLP-1 injections, eating smaller portions of nutrient-dense foods becomes even more important to avoid nausea and get maximum nutritional benefit. Try our GLP-1 weight loss calculator to explore medication options alongside dietary changes.
- 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 foods fill you up fastest for weight loss?
Protein and fibre are most satiating. Lean meats, fish, eggs, beans, lentils, and high-fibre vegetables (broccoli, spinach, peppers) keep you full longest. Whole grains like oats also help maintain steady blood sugar. These foods prevent the energy crashes that lead to snacking.
Can you lose weight by only changing what you eat?
Yes, weight loss primarily comes from a calorie deficit, which food choices control. However, the NHS recommends combining dietary changes with increased physical activity for faster results, better health outcomes, and to preserve muscle mass. Activity also improves mental health during weight loss.
Is it safe to follow a very strict diet for fast weight loss?
The NHS advises against gradual weight management without medical supervision. Losing 0.5–1 kg per week is sustainable and safe. Extremely restrictive diets cause muscle loss, nutritional deficiencies, and are hard to maintain long-term. Your GP can advise on safe approaches for your individual health.
Should I count calories to lose weight?
Calorie awareness helps, but it's not essential for everyone. Understanding portion sizes and choosing filling, nutritious foods often achieves results without strict counting. If you plateau, tracking calories can reveal where adjustments are needed. A GP or dietitian can recommend the best approach for you.
How do weight loss injections affect what I should eat?
Medications like Mounjaro and Wegovy slow stomach emptying and reduce appetite, so you naturally eat smaller portions. You'll need to eat slowly, choose nutrient-dense foods, and avoid very fatty or sugary foods to prevent nausea. Adequate protein remains important to preserve muscle during weight loss.
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.