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
Does Warm Water Help With Weight Loss?
Warm water is often suggested as a simple weight loss aid, but the evidence is limited. While staying hydrated is essential for health and may support weight management, drinking warm water alone won't cause significant weight loss. However, it can be part of a broader weight management strategy alongside diet, physical activity, and (if appropriate) prescription weight loss medication. For personalised guidance on effective weight loss approaches, your GP can assess your individual needs and discuss options that work 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.
What the Evidence Shows About Warm Water
Research on warm water and weight loss is modest. Some small studies suggest that drinking water before meals may help people eat slightly less by promoting feelings of fullness, but the effect is typically small — around 75–90 additional calories burned per day, equivalent to roughly 2–3kg weight loss over a year if combined with other changes.
Warm water itself has no special properties compared to room-temperature or cold water for weight loss. The benefit comes from hydration itself, not the temperature. Being well-hydrated supports metabolism and can help reduce thirst being mistaken for hunger.
For effective weight loss, the NHS recommends combining dietary changes with increased physical activity. If you need additional support, prescription weight loss medications like GLP-1 injections (such as Mounjaro or Wegovy) may be considered through specialist services. Calculate your personal BMI using our free BMI calculator above to understand your current weight status and what healthy weight means for you.
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.
Effective Weight Loss Strategies in the UK
Sustainable weight loss UK guidance focuses on a calorie deficit of around 500 kcal per day, which typically results in losing 0.5–1kg per week. This combines balanced nutrition with regular physical activity.
Beyond hydration, proven approaches include reducing sugary drinks, increasing fibre intake, and managing portion sizes. The NHS Weight Loss Plan offers free digital support.
For adults with a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes or high blood pressure, prescription weight loss medication may be available through NHS specialist services or via private prescribing. Our GLP-1 weight loss calculator can help you understand potential outcomes with evidence-based medications. Track your progress with our free progress tracker to stay motivated throughout your weight loss journey.
- 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 drinking warm water help me lose weight?
Warm water alone won't cause significant weight loss. However, staying hydrated supports metabolism and can help prevent mistaking thirst for hunger. Weight loss requires a calorie deficit through diet and physical activity combined with hydration.
How much water should I drink daily for weight loss?
The NHS recommends around 6–8 glasses (1.5 litres) of fluid daily for adults. Drinking water before meals may help with portion control, but the effect is modest. Focus on overall calorie balance rather than water temperature.
Is warm water better than cold water for weight loss?
No. Temperature doesn't affect weight loss. Both warm and cold water provide the same hydration benefits. Some people find warm water more comforting, which may encourage them to drink more — that's the only potential advantage.
What's the most effective way to lose weight in the UK?
The NHS recommends a combination of reduced-calorie eating (500 kcal deficit per day), increased physical activity, and behaviour change. For eligible adults, prescription weight loss medication through NHS specialist services or private prescribing may provide additional support alongside lifestyle changes.
Can I use the NHS Weight Loss Plan alongside other weight management methods?
Yes. The NHS Weight Loss Plan works best as part of a comprehensive approach including physical activity, dietary changes, and hydration. If you're eligible for prescription weight loss medication, this would be assessed and prescribed separately through your GP or a specialist service.
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.