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 Kefir Help With Weight Loss?
Kefir is a fermented dairy drink rich in probiotics and protein, which may support digestive health and satiety. However, kefir alone is not a weight loss solution. For sustainable weight management in the UK, evidence supports a combination of dietary changes, physical activity, and — for eligible adults — prescription medications like Mounjaro and Wegovy. This guide explains what kefir can offer and what clinically proven options are available through the NHS or private prescribing.
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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-Licensed Prescription Weight Loss Options
If you're interested in weight management in the UK, several prescription medications have been clinically proven to support weight loss alongside lifestyle changes.
- Mounjaro (tirzepatide) — a dual GIP and GLP-1 receptor agonist. Clinical trials showed participants lost an average of 15–21% of their body weight over 72 weeks, though individual results vary.
- Wegovy (semaglutide) — a GLP-1 receptor agonist. STEP trials demonstrated average weight loss of approximately 15% body weight at 68 weeks alongside diet and exercise.
- Saxenda (liraglutide) — a daily GLP-1 injection. Evidence supports meaningful weight loss when combined with calorie reduction and increased activity.
All three are prescription-only medicines and require a clinical assessment by a GP or licensed prescriber to determine eligibility and suitability.
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.
Eligibility and How to Access Weight Loss Support in the UK
You may be eligible for prescription weight loss medication in the UK if you have a BMI of 30 or above, or a BMI of 27–29.9 with weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea. Access is available through two routes: NHS specialist tier 3 weight management services (via GP referral) or private online prescribing following a clinical assessment. Your GP can advise on NHS availability in your area or discuss private options. Using our free BMI calculator, you can check where your weight sits and start a conversation with your healthcare provider about the best approach for you.
- 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.
Does kefir have any weight loss benefits?
Kefir contains probiotics, protein, and may support digestive health and satiety — factors that can assist general wellness. However, kefir alone does not cause weight loss. Sustainable weight management requires a calorie deficit, physical activity, and consistent lifestyle changes. For clinical-grade support, prescription medications are available in the UK for eligible adults.
What's the difference between Mounjaro and Wegovy for weight loss?
Mounjaro (tirzepatide) is a dual GIP and GLP-1 agonist; Wegovy (semaglutide) is a GLP-1 agonist only. Clinical trials showed Mounjaro produced slightly higher average weight loss (15–21% vs ~15%), but individual results vary significantly. Both are once-weekly injections, prescription-only, and require clinical assessment.
Am I eligible for prescription weight loss medication on the NHS?
Potentially, if you have a BMI of 30 or above, or 27–29.9 with weight-related health conditions. Eligibility varies by region, and NHS access is typically through specialist tier 3 services. Your GP can assess your suitability and discuss options available in your area.
What is the safest rate of weight loss in the UK?
The NHS recommends losing 0.5–1 kg (1–2 lbs) per week for sustainable, healthy weight loss. Faster loss is possible with medical support but increases muscle loss risk. Use our progress tracker to monitor steady, healthy weight changes over time.
Can I get prescription weight loss medication privately if the NHS has a waiting list?
Yes. Private online prescribing is available in the UK through licensed prescribers and GPhC-registered pharmacies. You complete a clinical assessment, and if approved, receive a prescription dispensed by the pharmacy. This route bypasses NHS waiting lists but involves private costs (typically £129–£320+ per month depending on dose).
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.