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
Do Sauna Suits Help With Weight Loss?
Sauna suits are marketed as a quick weight loss solution, but the reality is more complicated. While they can cause rapid water weight loss through sweating, this is temporary and not the same as losing fat. If you're looking for sustainable weight management in the UK, understanding what actually works — from lifestyle changes to prescription weight loss medication — is essential for long-term health.
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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 Sauna Suits Work and Why Weight Loss Appears Fast
Sauna suits are insulated garments designed to trap body heat and increase sweating during exercise. When you wear one, you sweat profusely, which can result in gradual weight management on the scales within hours — sometimes 2–3 kg or more depending on how much fluid you lose. However, this is water weight only, not fat loss.
- Water weight returns within 24 hours of rehydrating — as soon as you drink fluids, the weight comes back
- Fat loss requires a calorie deficit sustained over time, not increased sweating
- Sauna suits do not increase the number of calories you burn during exercise — they only increase fluid loss
- Dehydration from excessive sweating can actually impair exercise performance and recovery
The NHS recommends losing weight at a sustainable rate of 0.5–1 kg per week through balanced nutrition and physical activity. Water weight loss from sauna suits does not contribute to this goal.
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.
Evidence-Based Weight Loss That Actually Works
Real, sustainable weight loss requires a calorie deficit — consuming fewer calories than you burn. This can be achieved through dietary changes, increased physical activity, or a combination of both. For many people, especially those with a BMI of 30 or above, prescription weight loss medication prescribed by a GP or through specialist services can support this process alongside lifestyle changes.
For significant weight management in the UK, options include NHS tier 3 specialist weight management services, or private prescription weight loss treatment following clinical assessment. Calculate your BMI using our free BMI calculator above to understand where you sit on NHS health thresholds, and use our progress tracker to log genuine fat loss over weeks and months — not water fluctuations from sauna suits.
Real, sustainable weight loss requires a calorie deficit — consuming fewer calories than you burn. This can be achieved through dietary changes, increased physical activity, or a combination of both. For many people, especially those with a BMI of 30 or above, prescription weight loss medication can support this process alongside lifestyle changes when prescribed by a GP or specialist.
For genuine weight management in the UK, explore NHS tier 3 specialist weight loss services or private prescription options following clinical assessment. Check your BMI using our free tool above to see where you stand on health thresholds, and track real progress with our weight loss progress tracker — measuring actual fat loss over weeks and months, not temporary water fluctuations.
- 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.
Will I lose real weight using a sauna suit?
No. Sauna suits cause water loss through sweating, not fat loss. The weight you lose returns within 24 hours of drinking fluids. Real fat loss requires a sustained calorie deficit over weeks and months, which sauna suits do not create.
Can sauna suits help during exercise?
Sauna suits do not increase calorie burn during exercise — they only increase sweating and fluid loss. Dehydration can actually reduce exercise performance and recovery. Standard exercise clothing is safer and equally effective for weight management.
What is the safest way to lose weight according to the NHS?
The NHS recommends losing 0.5–1 kg per week through a combination of reduced-calorie diet and increased physical activity. For those with a BMI of 30 or above, or 27–29.9 with weight-related health conditions, prescription weight loss medication may be prescribed through specialist services.
Are there prescription weight loss options available in the UK?
Yes. GLP-1 prescription medications like Wegovy (semaglutide) and Mounjaro (tirzepatide) are licensed for weight management in the UK. Access is through NHS specialist tier 3 services or private prescription following clinical assessment. These work alongside diet and exercise, not instead of them.
How can I tell if I'm making real weight loss progress?
Real progress is measured over weeks and months, not hours or days. Use our free progress tracker to log your weight weekly and spot genuine downward trends. A BMI calculator also shows whether your weight change is moving you into a healthier category.
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.