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
Can You Eat Bread When Losing Weight?
Yes, you can include bread in a weight loss plan — it's about choosing the right type and managing portions. Whole grain, seeded, and sourdough breads offer more fibre and keep you fuller longer than white bread. However, bread is calorie-dense, so portion control matters. If you're struggling with weight management despite dietary changes, prescription medication may be an option. In the UK, GLP-1 weight loss injections like Mounjaro and Wegovy are available for eligible adults alongside lifestyle modifications. Your GP can assess whether prescription weight loss support is right for you.
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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 Prescription Weight Loss Options
If dietary adjustments like choosing wholemeal bread aren't delivering results, prescription weight management medications are available through the NHS and privately in the UK. Three main options are currently licensed:
- Mounjaro (tirzepatide) — a dual GIP and GLP-1 receptor agonist administered once weekly, with clinical trials showing average weight loss of 15–21% of body weight
- Wegovy (semaglutide) — a GLP-1 receptor agonist given once weekly, associated with average weight loss of approximately 15% in clinical trials
- Saxenda (liraglutide) — a daily GLP-1 injection, offering another once-daily option
Eligibility typically requires a BMI of 30 or above, or 27 or above with weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea. These medications work alongside reduced-calorie diet and increased physical activity — they are not replacements for lifestyle change.
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.
How to Access Weight Loss Support in the UK
NHS route: Speak to your GP about referral to a specialist weight management service (tier 3). Availability and waiting times vary significantly by region. Many areas have lengthy waiting lists, though some regions offer faster access.
Private route: Online prescribing is available through GPhC-registered pharmacies following a clinical assessment with a UK-licensed prescriber. This route does not require NHS referral.
To check your starting point, use our free BMI calculator above to see where you fall on the NHS weight categories. Your GP can then discuss whether prescription medication, combined with dietary changes and the support of our GLP-1 weight loss calculator, is appropriate for your circumstances.
- 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 wholemeal bread better for weight loss than white bread?
Yes. Wholemeal and seeded breads contain more fibre, which slows digestion, helps you feel fuller longer, and supports steadier blood sugar. White bread is refined, digests quickly, and may leave you hungry sooner. However, all bread is calorie-dense — portion control remains important regardless of type.
How much bread can you eat on a weight loss diet?
The NHS recommends a calorie deficit of around 500 kcal per day for gradual, sustainable weight loss. A typical slice of wholemeal bread contains 80–100 kcal. Incorporate it into your daily calorie allowance rather than eliminating it entirely. Most sustainable diets include bread as part of balanced meals.
Can weight loss medication help if diet alone isn't working?
Yes. If you've made dietary changes — including choosing higher-fibre breads and managing portions — but weight management remains difficult, prescription GLP-1 medications like Mounjaro and Wegovy may help. They're available for eligible adults in the UK through NHS specialist services or private prescribing. Eligibility depends on BMI and health circumstances.
What's the difference between NHS and private weight loss medication access?
NHS access requires GP referral to a specialist tier 3 weight management service, with variable waiting times across regions. Private access is through online assessment with a UK-licensed prescriber and GPhC-registered pharmacy, available without NHS referral. Both require clinical assessment; private options are typically faster but involve out-of-pocket costs.
Should I try diet changes before considering weight loss medication?
The NHS recommends starting with lifestyle changes — diet and activity — as the foundation. Prescription medications are typically considered when these changes alone haven't achieved sufficient results over a reasonable period. Many people benefit from combining both approaches: dietary modifications (like choosing nutritious breads), increased activity, and medication support together.
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.