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 Lukewarm Water Help With Weight Loss?
Drinking lukewarm water is often recommended as a simple weight loss strategy, but the evidence for its direct impact on weight loss is limited. While staying hydrated is essential for health, water alone does not burn significant calories or create the calorie deficit needed for weight management. However, drinking water before meals may help you feel fuller, reducing overall food intake. For sustainable weight loss in the UK, a combination of dietary changes, physical activity, and in some cases prescription weight loss medication is more effective than water alone.
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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 Does Science Say About Water and Weight Loss?
Research shows that drinking water has modest benefits for weight management, but not in the way many people expect. Water does not boost metabolism significantly — the calories burned from heating water in your body (thermogenesis) are minimal. However, studies do support the idea that drinking water before meals may reduce hunger and increase feelings of fullness, potentially leading to eating less overall.
- Drinking 500ml of water before meals may reduce calorie intake by 5–10% in some people
- Staying hydrated supports kidney function and helps your body process nutrients efficiently
- Lukewarm water is no more effective than cold water — temperature makes no meaningful difference
- Water has zero calories, making it a healthier choice than sugary drinks for weight management
The NHS recommends drinking 6–8 glasses of fluid daily as part of a healthy lifestyle, but this alone will not lead to sustained weight loss. For effective weight management in the UK, a reduced-calorie diet and increased physical activity remain the evidence-based foundation.
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 Beyond Water
If you're struggling with weight management, drinking water is a helpful habit but should be part of a broader approach. A calorie deficit of around 500 calories per day typically results in losing approximately 0.5 kg per week — the NHS-recommended safe rate.
- Dietary changes: Eating more whole foods, vegetables, and protein-rich foods supports satiety and weight loss
- Physical activity: Regular exercise (150 minutes moderate activity per week) improves health outcomes
- Prescription weight loss medication: For eligible adults, medications like Mounjaro or Wegovy may help alongside lifestyle changes
- NHS support: Your GP can refer you to specialist weight management services if needed
Use our free BMI calculator above to assess your current weight category, and our GLP-1 weight loss calculator to explore potential outcomes with prescription support.
- 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 lukewarm water speed up my metabolism?
No. Drinking water has minimal effect on metabolism. The calories burned from heating water (thermogenesis) are negligible. However, water supports overall health and staying hydrated is important for normal body function. For genuine metabolic support, focus on diet, physical activity, and if eligible, consult your GP about prescription weight loss options.
Is lukewarm water better than cold water for weight loss?
No. There is no meaningful difference between lukewarm and cold water for weight loss. Some studies suggest cold water may slightly increase calorie burn, but the effect is too small to matter. What matters is drinking enough fluid daily — around 6–8 glasses — and combining this with a reduced-calorie diet and exercise.
How much water should I drink daily for weight loss?
The NHS recommends 6–8 glasses of fluid daily for general health — this typically means about 1.5–2 litres. Drinking water before meals may help reduce hunger, but there is no "clinically supported" amount for weight loss. Individual needs vary based on activity level, climate, and health status. Your GP can provide personalised guidance.
Can water alone help me lose weight?
Water alone will not create the calorie deficit needed for weight loss. However, drinking water instead of sugary drinks, and drinking water before meals to reduce hunger, supports weight management as part of a broader strategy. For sustained weight loss, combine hydration with a reduced-calorie diet, physical activity, and if appropriate, prescription weight loss treatment prescribed by your GP.
What's the most effective way to lose weight in the UK?
The NHS recommends a combination of reduced-calorie diet, increased physical activity (150 minutes per week), and behavioural changes. For adults with a BMI of 30 or above, or 27–29.9 with weight-related health conditions, prescription weight loss medication may be suitable following clinical assessment. Your GP can refer you to specialist services or discuss options. Start by calculating your BMI using our free tool above.
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.