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
Will Depression Cause Weight Loss? Understanding the Link
Depression can affect your weight in different ways — some people lose weight, others gain it. When depression impacts your appetite, energy levels, or eating patterns, it can lead to weight changes. If you're experiencing depression alongside weight loss or other symptoms, it's important to speak with your GP. They can assess your mental health and discuss weight management options suitable for you, including prescription treatments now available through NHS services and private prescribing 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.
UK Weight Management Options Available
If you're struggling with weight management alongside other health concerns, several UK-licensed prescription options are now available. For eligible adults, GLP-1 weight loss medications such as Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide) offer evidence-based support.
- Mounjaro: A dual GIP and GLP-1 receptor agonist; clinical trials showed average weight loss of 15–21% of body weight over 72 weeks when combined with a reduced-calorie diet and physical activity.
- Wegovy: A GLP-1 receptor agonist; trials demonstrated approximately 15% average weight loss at the maximum dose alongside lifestyle changes.
- Eligibility: Generally BMI 30 or above, or BMI 27–29.9 with weight-related health conditions such as type 2 diabetes, high blood pressure, or cardiovascular disease.
Calculate your personal BMI using our free BMI calculator above to check where you currently stand and discuss prescription options with your GP or a licensed prescriber.
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 vs Private Access — How to Get Started
In the UK, prescription weight loss medication is accessible through two routes. NHS access is through specialist tier 3/4 weight management services following GP referral, though availability and waiting times vary significantly by region. Private access is available through GPhC-registered online prescribers following a clinical assessment, without requiring an NHS referral.
If depression or other health concerns are affecting your weight, your first step should be speaking with your GP. They can assess whether prescription weight loss treatment is appropriate, refer you to specialist services if suitable, or discuss mental health support alongside weight management. Track progress with our free progress tracker to monitor any changes as you work with your healthcare team.
- 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 depression directly cause weight loss?
Yes, depression can cause weight loss in several ways. It may reduce appetite, lower energy levels, reduce motivation to eat, or cause changes in metabolism. Weight loss from depression is typically unintentional. However, some people experience weight gain with depression instead. If you're experiencing unexplained weight changes alongside low mood, speak with your GP for proper assessment.
What are the UK weight loss medication options if I'm struggling with weight?
Three prescription medications are UK-licensed for weight management: Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide). All are GLP-1 or dual GLP-1/GIP receptor agonists that may help reduce appetite and support weight loss alongside diet and exercise. Access is through NHS specialist services or private prescribing following clinical assessment.
How do I know if I'm eligible for prescription weight loss medication in the UK?
Eligibility typically requires a BMI of 30 or above, or BMI 27–29.9 with weight-related health conditions like type 2 diabetes, high blood pressure, or sleep apnoea. Your GP can assess your individual eligibility and discuss whether prescription treatment is appropriate for your circumstances.
Can I access weight loss medication through the NHS if I have depression?
Yes. NHS weight management services consider your overall health, including mental health conditions. Depression does not exclude you from eligibility. Speak with your GP about referral to tier 3 specialist weight management services in your area. They can assess you holistically and discuss treatment options.
What's the difference between NHS and private weight loss medication access?
NHS access is through specialist weight management services following GP referral, with variable waiting times depending on your region. Private access is available through GPhC-registered online prescribers without NHS referral, following an online clinical assessment. Both routes require a prescription from a licensed prescriber and eligibility assessment.
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.