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
7 Day Flat Stomach Diet Plan For Weight Loss
A 7 day flat stomach diet plan can help reduce bloating and support initial weight loss, but sustainable results require longer-term changes. While short-term plans can motivate, genuine weight management in the UK typically involves creating a calorie deficit over weeks and months. Many people also combine diet with increased physical activity, and some eligible adults explore prescription weight loss medication through their GP or private prescribers. This guide covers evidence-based dietary approaches, realistic expectations, and UK prescription options that complement lifestyle changes.
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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.
UK Weight Loss Options: Diet, Lifestyle, And Prescription Medication
A 7 day flat stomach plan typically focuses on reducing sodium and refined carbohydrates to minimise bloating, alongside a calorie deficit to support fat loss. However, the NHS emphasises that sustainable weight management requires ongoing changes rather than short-term fixes. A realistic approach combines reduced-calorie eating (aiming for a 500 kcal daily deficit to lose approximately 0.5 kg per week) with increased physical activity.
For eligible adults in the UK, prescription weight loss medication is now available alongside diet and exercise. Mounjaro (tirzepatide) and Wegovy (semaglutide) are GLP-1 receptor agonists licensed for weight management. Mounjaro, a dual GIP and GLP-1 agonist, showed average weight loss of 15–21% in clinical trials. Wegovy showed approximately 15% average weight loss. Both require a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes or hypertension.
Access in the UK is through NHS specialist tier 3 weight management services (referral from GP, longer waiting times) or private online prescribing following a clinical assessment. Use our free GLP-1 weight loss calculator to estimate potential results at different doses.
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.
NHS Versus Private: How To Access Weight Management Support
The NHS weight loss pathway includes tier 1 (self-help and community programmes), tier 2 (primary care-based behaviour change), tier 3 (specialist multidisciplinary services where prescription medication may be offered), and tier 4 (bariatric surgery for severe obesity). Tier 3 access requires a GP referral and availability varies significantly across regions—waiting lists can extend months or years in some areas.
Private prescription weight loss is available immediately through GPhC-registered online pharmacies following an online clinical assessment with a UK-licensed prescriber. Costs range from approximately £129–£320 monthly depending on dose and provider. Both routes require a clinical assessment to confirm eligibility and suitability. Start by discussing your weight health with your GP, who can advise on NHS options or support a private route. Track your progress using our free progress tracker regardless of which path you choose.
- 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.
Can a 7 day diet plan give permanent weight loss results?
No. A 7 day plan can jumpstart motivation and reduce bloating short-term, but lasting weight loss requires sustained calorie deficit and lifestyle change over weeks and months. Most people regain short-term losses without ongoing dietary and activity habits. NHS guidance recommends gradual, sustainable approaches targeting 0.5–1 kg per week loss.
What is the best diet for a flat stomach?
There is no single "best" diet. Evidence supports Mediterranean-style eating, reduced refined carbohydrates, increased fibre, and adequate protein for satiety. Minimising sodium and added sugars reduces bloating. The most effective diet is one you can sustain long-term alongside physical activity. Your GP or a registered dietitian can advise on options suited to your health.
How do prescription weight loss injections work?
GLP-1 medications like Wegovy mimic a natural gut hormone that signals fullness, reduces appetite, and slows gastric emptying. Mounjaro is a dual GIP/GLP-1 agonist with similar effects via two hormone pathways. Both are used alongside reduced-calorie diet and increased physical activity. Individual results vary; eligibility requires BMI assessment and clinical evaluation.
Am I eligible for weight loss medication on the NHS?
NHS eligibility typically requires BMI of 30 or above, or 27–29.9 with weight-related conditions (diabetes, hypertension, sleep apnoea, cardiovascular disease). South Asian, Chinese, Black African, and Black Caribbean adults have lower thresholds due to higher health risks at the same BMI. Your GP can assess your eligibility and refer you to specialist services if appropriate.
How quickly will I lose weight with a diet plan plus medication?
Weight loss varies greatly between individuals. Clinical trials showed Mounjaro users lost an average of 15–21% body weight, and Wegovy users approximately 15%, but these are averages alongside reduced-calorie diet and activity. Use our GLP-1 weight loss calculator to estimate potential loss at different doses. Results depend on dose, adherence, diet, activity, genetics, and metabolism.
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.