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's the Easiest Weight Loss Diet?
There's no single "easiest" weight loss diet that works for everyone, but evidence shows that the most sustainable approaches combine modest calorie reduction with lifestyle changes you can actually stick to. The NHS recommends losing weight at a rate of 0.5 to 1 kg per week for healthy, long-term results. Success depends less on which specific diet you choose and more on finding an approach that fits your lifestyle, preferences, and health circumstances. Whether that's intermittent fasting, Mediterranean-style eating, or working with a weight management professional, the key is consistency and realistic expectations.
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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.
Evidence-Based Diet Approaches That Work
Several evidence-based weight loss approaches have strong research support for sustainable results:
- Calorie deficit method: Losing approximately 0.5 kg per week requires a deficit of around 500 kcal daily. This is often considered the "easiest" because it's flexible — you can eat foods you enjoy as long as portions are controlled. Use our free BMI calculator to establish your current baseline and healthy weight range.
- Mediterranean diet: Emphasises whole grains, vegetables, fish, and healthy fats. Evidence shows this supports weight management alongside cardiovascular health benefits.
- Intermittent fasting (16:8 or 5:2): Some people find meal timing restrictions easier than daily calorie counting. Results are similar to standard calorie restriction when overall intake is controlled.
- Low carbohydrate approaches: Can be effective short-term, though long-term weight loss outcomes match standard calorie reduction.
The NHS weight management pathway recommends starting with self-help approaches and behaviour change programmes before considering prescription weight loss medication.
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.
When to Consider Medical Support
If you've tried standard diet and exercise approaches without success, prescription weight loss medication may be an option. In the UK, adults with a BMI of 30 or above, or 27 or above with weight-related health conditions, may be eligible for specialist support. GLP-1 weight loss injections like Wegovy (semaglutide) or Mounjaro (tirzepatide) are prescription-only medicines available through NHS specialist services or private prescribing. Clinical trials show these can support an average weight loss of 15–21% of body weight, though individual results vary significantly. These medications work best alongside dietary changes and increased physical activity — they're a tool to support your efforts, not a replacement for lifestyle changes. Try our GLP-1 weight loss calculator to explore potential outcomes if prescription medication is something your GP recommends.
- 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 makes a weight loss diet "easy" to stick to?
The easiest diet is one you can maintain long-term without feeling deprived. This often means choosing an approach that fits your food preferences, lifestyle, and social circumstances. A 500 kcal daily deficit is sustainable for most people. Success depends more on consistency than the specific diet type.
Is there an easiest weight loss diet recommended by the NHS?
The NHS doesn't promote one specific diet. Instead, it recommends a sustained calorie deficit of about 500 kcal daily for 0.5 kg weekly loss, combined with increased physical activity. The easiest approach is whatever you can stick to — Mediterranean diet, intermittent fasting, or standard calorie control all work if you maintain the deficit.
How fast should weight loss happen?
The NHS recommends 0.5 to 1 kg per week as the safest, most sustainable rate. Faster loss increases muscle loss risk and is harder to maintain. Aiming for this pace helps preserve muscle mass and makes the process feel more manageable, making it genuinely easier to continue.
When should I consider weight loss medication instead of dieting alone?
If you've tried diet and exercise for several months without adequate progress, or if you have a BMI of 30 or above (or 27+ with weight-related health conditions), speak to your GP about specialist weight management services. Prescription options exist, but they're used alongside — not instead of — dietary and lifestyle changes.
Can weight loss injections like Wegovy make weight loss easier?
Wegovy (semaglutide) is a GLP-1 injection that may help reduce appetite and support feeling fuller after smaller meals. Clinical trials showed average weight loss of about 15% of body weight at the maximum dose. It's prescription-only and works best with reduced-calorie diet and exercise. Your GP or prescriber can assess if it's suitable for you.
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.