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
Weight Loss and Liver Problems — What You Need to Know
Excess weight can significantly affect liver health, leading to conditions like non-alcoholic fatty liver disease (NAFLD). Many people wonder whether weight loss helps reverse liver damage and what methods are safe if they have existing liver problems. The good news is that losing weight — even just 5 to 10% of your body weight — can improve liver function and reduce fat accumulation in liver cells. This guide explains the connection between weight management and liver health, based on NHS guidance and current evidence. Use our free BMI calculator to check whether your current weight puts you at increased health risk, and discover evidence-based approaches to safe weight loss in the UK.
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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.
How Excess Weight Affects Your Liver
Non-alcoholic fatty liver disease (NAFLD) affects approximately 1 in 3 UK adults, often linked to excess weight. When you carry excess body fat, your liver stores more fat cells, which can cause inflammation and damage over time. This condition can progress to more serious liver disease if left unmanaged.
Key facts about weight and liver health:
- Losing just 5% of body weight can reduce liver fat significantly
- A clinically studied weight loss may reverse some early-stage liver damage
- Rapid or very low-calorie dieting can sometimes worsen liver problems — sustainable loss is safer
- Regular physical activity combined with healthy eating supports both weight loss and liver recovery
- Weight loss medication may be considered as part of NHS weight management, though individual assessment is essential
If you have diagnosed liver disease, always consult your GP before starting any weight loss programme or medication, as some approaches may require specialist monitoring.
Clinically BackedWeight Loss
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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.
Weight Loss Methods and Liver Safety
For adults with liver concerns, safe weight loss in the UK involves a moderate calorie deficit of around 500 kcal per day, supporting a loss of approximately 0.5 to 1 kg per week. The NHS recommends this gradual approach because gradual weight management can sometimes stress the liver further. Prescription weight loss medication may be offered through NHS specialist weight management services or private clinical assessment, but must be reviewed individually if liver problems exist.
Always discuss your liver health with your GP before starting any weight loss plan, medication, or intensive diet. Our GLP-1 weight loss calculator can help you understand potential outcomes, though any medication must be prescribed following proper clinical evaluation of your liver function.
- 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 weight loss reverse fatty liver disease?
Yes, evidence shows that losing 5 to 10% of body weight can reduce liver fat and improve liver function in early-stage NAFLD. Greater weight loss (15% or more) may reverse some of the inflammation. However, results depend on the stage of disease and individual factors — always seek GP advice for personalised guidance.
Is it safe to use weight loss injections if I have liver problems?
Weight loss medications like Wegovy (semaglutide) require individual clinical assessment, especially with existing liver disease. Some medications may need dose adjustments or monitoring. Always inform your prescriber of any liver condition before starting treatment — they will assess whether it is safe for you.
What is the safest rate of weight loss for liver health?
The NHS recommends losing 0.5 to 1 kg per week through a balanced diet and physical activity. This gradual approach is gentler on the liver than gradual weight management, which can sometimes increase liver stress. Very low-calorie diets should only be followed under medical supervision.
How does the NHS approach weight management for people with fatty liver disease?
NHS weight management is typically delivered through tier 1 (self-help), tier 2 (primary care), or tier 3 (specialist services). If you have liver disease, your GP may refer you to a specialist weight management service that can monitor your liver function alongside weight loss progress.
Can lifestyle changes alone help if I have fatty liver disease?
Yes, lifestyle changes including a healthy diet, regular physical activity, and alcohol reduction (if applicable) are often first-line treatment. Most people with NAFLD benefit from gradual weight loss without medication. Your GP can advise whether additional support or medication is appropriate for your situation.
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.